f0nzie/tikz_favorites

\documentclass[tikz,border=5]{standalone}

\usetikzlibrary{fadings}
\tikzfading[name=fade out,
inner color=transparent!0, outer color=transparent!100]

\def\factor{4}
\def\xradius{2}
\def\yradius{2/\factor}
\def\height{1.05cm}
\def\xandy{2 and 2/\factor}

\tikzset{
  pics/.cd, %
  disc/.style ={
    code = {
      %% the foundation
      \path [fill=black!15] (-\xradius,0) -- (-\xradius,-\height) arc
      (180:360:\xandy) -- (\xradius,0) arc (0:180:\xandy);%
      \path [top color=black!25, bottom color=white, opacity=0.2] (0,0) ellipse
      [x radius=\xradius, y radius =\yradius];%
      \path [left color=black!25, right color=black!15] (-\xradius,0) --
      (-\xradius,-\height) arc (180:240:\xandy) -- +(0,\height) arc
      (240:180:\xandy);%
      \path [left color=black!15, right color=black!30] (\xradius,0) --
      (\xradius,-\height) arc (360:320:\xandy) -- +(0,\height) arc
      (320:360:\xandy);

      %% rays in front
      \foreach \col/\r/\shift/\stop/\opacity in {%
        black/205/25/20/100, %
        black/295/35/30/100, %
        black/295/30/30/200, %
        black/295/25/20/300, %
        white/245/14/14/100, %
        white/245/12/12/20, %
        white/245/10/10/10} {%
        \foreach \i [evaluate={\opposite=\r-180;}] in {0,1,...,\stop}{%
          \fill [\col, fill opacity = 1/\opacity] (\opposite:0.1 and
          0.1/\factor) -- (\r+\shift-\i:\xandy) -- ++(0,-\height) arc
          (\r+\shift-\i:\r-\shift+\i:\xandy) -- +(0,\height) -- cycle; }}

      %% rays in back
      \foreach \r/\shift/\stop/\opacity in {%
        25/25/20/100, %
        115/35/3/150,%
        115/30/23/100} {%
        \foreach \i [evaluate={\opposite=\r-180;}] in {0,1,...,\stop}{%
          \fill [black, fill opacity = 1/\opacity] (\opposite:0.1 and 0.1/\factor) --
          (\r+\shift-\i:\xandy) arc (\r+\shift-\i:\r-\shift+\i:\xandy) --
          cycle; }}

      %% masking the four edges in the center
      \foreach \i in {0.1, 0.2, ..., 0.4}%
      \fill[black!15, opacity=0.7, path fading=fade out] 
      (0,0) ellipse[x radius=\i, y radius =\i/\factor];

      %% the light and the dark arcs
      \foreach \i [evaluate={\start=185+10*\i; \finish=355-10*\i;}]%
      in {0.1, 0.2, ..., 1.5}{%
        \draw[white, opacity=0.04, line width=\i, yshift=0.02cm]
        (\start:\xandy) arc (\start:\finish:\xandy);

        \draw[black!80, opacity=0.05, line width=\i, yshift=-\height]
        (\start:\xandy) arc (\start:\finish:\xandy); }
    }
  },% 
  disc bottom/.style = {
    code = {
      \foreach \i/\opacity in {%
        1/20,2/20,3/20,4/30,5/35,6/40,7/60,8/80,9/100,10/100,11/100,12/100}%
        \fill [black, fill opacity = 1/\opacity, yshift=-0.03cm] (0,-\height)
        ellipse [x radius = \xradius+\i/40, y radius = \yradius+\i/20/\factor]; 
      \path pic {disc};
    }
  },%
  disc top/.style = {
    code = {
      \foreach \i/\opacity in {%
        2/60, 3/55, 4/50,5/40, 6/35, 7/30, 8/20, 9/20, 10/20, 11/20, 12/20,
        13/20, 14/20, 15/20, 16/20, 17/20, 18/20, 19/20, 20/20, 21/20, 22/20,
        23/20, 24/20, 25/20, 26/20}%
        \fill [black, fill opacity = 1/\opacity, yshift=-0.35cm] (0,-\height)
        ellipse [x radius = \xradius-\i/40, y radius = \yradius-\i/20/\factor];
      \path pic {disc};
    }
  }
}

\begin{document}
\begin{tikzpicture}
  \path (0,0) pic {disc bottom} (0,1.4) pic {disc top} (0,2.8) pic {disc top};
\end{tikzpicture}
\end{document}

% http://pgfplots.net/media/tikz/examples/TEX/intersection-surfaces.tex
% +3d+pgf
% compile with lualatex
%
\documentclass[border=10pt]{standalone}
%%%<
\usepackage{verbatim}
%%%>
\usepackage{pgfplots}
\pgfplotsset{width=7cm,compat=1.8}

\begin{comment}
:Title: Intersection of two surfaces
:Tags: 3D;Intersections
:Author: Jake
:Slug: intersection-surfaces

We would like to intersect a 3D plot with a plane. The problem is not to get
the two functions into a plot, but to get the two functions to visual
intersect with each other, i.e the nearest surface is in the foreground.

This can't be done automatically, unfortunately, since pgfplots can't do z
buffering between different \addplot commands.

For this concrete application, you could construct the plot "by hand", however:

First, you draw the part of the cone below 0, then you draw the plane and the
circle, then you draw the part of the cone above 0.

I've used a polar coordinate system for this, since it makes the input of
polar functions easier.

This code was written by Jake on TeX.SE.
\end{comment}

\begin{document}
  \begin{tikzpicture}
    \begin{axis}[grid=major,view={20}{40},z buffer=sort, data cs=polar]
      \addplot3 [surf, domain=0:360, domain y=5:10,samples=30, samples y=10]
      {-y+5};
      \addplot3 [data cs=cart,surf,domain=-10:10,samples=2, opacity=0.5]
      {0};
      \addplot3 [domain=0:360, samples y=0, samples=30, thick, z buffer=auto]
      (x,5.1,0);
      \addplot3 [surf,domain=0:360, domain y=0:5,samples=30, samples y=10]
      {-y+5};
    \end{axis}
  \end{tikzpicture}  
\end{document}

% page 142 of book PGFPLOTS
% http://mirror.utexas.edu/ctan/graphics/pgf/contrib/pgfplots/doc/pgfplots.pdf
% arr: reindent
\documentclass[border=15pt]{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat=1.16}

\begin{document}
	
\begin{tikzpicture}
	\begin{axis}
		[
		axis lines=center,
		axis on top,
		xlabel={$x$},
		ylabel={$y$},
		zlabel={$z$},
		domain=0:1,y domain=0:2*pi,
		xmin=-1.5,
		xmax=1.5,
		ymin=-1.5,
		ymax=1.5,
		zmin=0.0,
		mesh/interior colormap=
		{blueblack}{color=(black) color=(blue)},
		colormap/blackwhite,
		samples=10,
		samples y=40,
		z buffer=sort,
		]
			\addplot3 [surf]
			({x*cos(deg(y))},{x*sin(deg(y))},{x});
	\end{axis}
\end{tikzpicture}
	
\end{document}

\documentclass[parskip]{scrartcl}
\usepackage[margin=15mm,landscape]{geometry}
\usepackage{tikz}
\usepackage{keyval}
\usepackage{ifthen}

\makeatletter
% Standard Values for Parameters
\newcommand{\tikzcuboid@shiftx}{0}
\newcommand{\tikzcuboid@shifty}{0}
\newcommand{\tikzcuboid@dimx}{4}
\newcommand{\tikzcuboid@dimy}{4}
\newcommand{\tikzcuboid@dimz}{4}
\newcommand{\tikzcuboid@scale}{1}
\newcommand{\tikzcuboid@densityx}{1}
\newcommand{\tikzcuboid@densityy}{1}
\newcommand{\tikzcuboid@densityz}{1}
\newcommand{\tikzcuboid@rotation}{0}
\newcommand{\tikzcuboid@anglex}{0}
\newcommand{\tikzcuboid@angley}{90}
\newcommand{\tikzcuboid@anglez}{225}
\newcommand{\tikzcuboid@scalex}{1}
\newcommand{\tikzcuboid@scaley}{1}
\newcommand{\tikzcuboid@scalez}{1}
\newcommand{\tikzcuboid@linefront}{}
\newcommand{\tikzcuboid@linetop}{}
\newcommand{\tikzcuboid@lineright}{}
\newcommand{\tikzcuboid@fillfront}{}
\newcommand{\tikzcuboid@filltop}{}
\newcommand{\tikzcuboid@fillright}{}
\newcommand{\tikzcuboid@newcoords}{N}
\newcommand{\tikzcuboid@filled}{N}
\newcommand{\tikzcuboid@shaded}{N}
% Definition of Keys
\define@key{tikzcuboid}{shiftx}[\tikzcuboid@shiftx]{\renewcommand{\tikzcuboid@shiftx}{#1}}
\define@key{tikzcuboid}{shifty}[\tikzcuboid@shifty]{\renewcommand{\tikzcuboid@shifty}{#1}}
\define@key{tikzcuboid}{dimx}[\tikzcuboid@dimx]{\renewcommand{\tikzcuboid@dimx}{#1}}
\define@key{tikzcuboid}{dimy}[\tikzcuboid@dimy]{\renewcommand{\tikzcuboid@dimy}{#1}}
\define@key{tikzcuboid}{dimz}[\tikzcuboid@dimz]{\renewcommand{\tikzcuboid@dimz}{#1}}
\define@key{tikzcuboid}{scale}[\tikzcuboid@scale]{\renewcommand{\tikzcuboid@scale}{#1}}
\define@key{tikzcuboid}{densityx}[\tikzcuboid@densityx]{\renewcommand{\tikzcuboid@densityx}{#1}}
\define@key{tikzcuboid}{densityy}[\tikzcuboid@densityy]{\renewcommand{\tikzcuboid@densityy}{#1}}
\define@key{tikzcuboid}{densityz}[\tikzcuboid@densityz]{\renewcommand{\tikzcuboid@densityz}{#1}}
\define@key{tikzcuboid}{rotation}[\tikzcuboid@rotation]{\renewcommand{\tikzcuboid@rotation}{#1}}
\define@key{tikzcuboid}{anglex}[\tikzcuboid@anglex]{\renewcommand{\tikzcuboid@anglex}{#1}}
\define@key{tikzcuboid}{angley}[\tikzcuboid@angley]{\renewcommand{\tikzcuboid@angley}{#1}}
\define@key{tikzcuboid}{anglez}[\tikzcuboid@anglez]{\renewcommand{\tikzcuboid@anglez}{#1}}
\define@key{tikzcuboid}{scalex}[\tikzcuboid@scalex]{\renewcommand{\tikzcuboid@scalex}{#1}}
\define@key{tikzcuboid}{scaley}[\tikzcuboid@scaley]{\renewcommand{\tikzcuboid@scaley}{#1}}
\define@key{tikzcuboid}{scalez}[\tikzcuboid@scalez]{\renewcommand{\tikzcuboid@scalez}{#1}}
\define@key{tikzcuboid}{linefront}[\tikzcuboid@linefront]{\renewcommand{\tikzcuboid@linefront}{#1}}
\define@key{tikzcuboid}{linetop}[\tikzcuboid@linetop]{\renewcommand{\tikzcuboid@linetop}{#1}}
\define@key{tikzcuboid}{lineright}[\tikzcuboid@lineright]{\renewcommand{\tikzcuboid@lineright}{#1}}
\define@key{tikzcuboid}{fillfront}[\tikzcuboid@fillfront]{\renewcommand{\tikzcuboid@fillfront}{#1}}
\define@key{tikzcuboid}{filltop}[\tikzcuboid@filltop]{\renewcommand{\tikzcuboid@filltop}{#1}}
\define@key{tikzcuboid}{fillright}[\tikzcuboid@fillright]{\renewcommand{\tikzcuboid@fillright}{#1}}
\define@key{tikzcuboid}{newcoords}[\tikzcuboid@newcoords]{\renewcommand{\tikzcuboid@newcoords}{#1}}
\define@key{tikzcuboid}{filled}[\tikzcuboid@filled]{\renewcommand{\tikzcuboid@filled}{#1}}
\define@key{tikzcuboid}{shaded}[\tikzcuboid@shaded]{\renewcommand{\tikzcuboid@shaded}{#1}}

% Commands
\newcommand{\tikzcuboid}[1]{
    \setkeys{tikzcuboid}{#1} % Process Keys passed to command
    \begin{scope}[xshift=\tikzcuboid@shiftx,yshift=\tikzcuboid@shifty,scale=\tikzcuboid@scale,rotate=\tikzcuboid@rotation]
    \pgfmathsetmacro{\steppingx}{1/\tikzcuboid@densityx}
    \pgfmathsetmacro{\steppingy}{1/\tikzcuboid@densityy}
    \pgfmathsetmacro{\steppingz}{1/\tikzcuboid@densityz}
    \newcommand{\dimx}{\tikzcuboid@dimx}
    \newcommand{\dimy}{\tikzcuboid@dimy}
    \newcommand{\dimz}{\tikzcuboid@dimz}
    \pgfmathsetmacro{\secondx}{2*\steppingx}
    \pgfmathsetmacro{\secondy}{2*\steppingy}
    \pgfmathsetmacro{\secondz}{2*\steppingz}
    \foreach \x in {\steppingx,\secondx,...,\dimx}
    {   \foreach \y in {\steppingy,\secondy,...,\dimy}
        {   \pgfmathsetmacro{\lowx}{(\x-\steppingx)}
            \pgfmathsetmacro{\lowy}{(\y-\steppingy)}
            \filldraw[fill=orange,draw=blue] (\lowx,\lowy,\dimz) -- (\lowx,\y,\dimz) -- (\x,\y,\dimz) -- (\x,\lowy,\dimz) -- cycle;

        }
    }
    \foreach \x in {\steppingx,\secondx,...,\dimx}
    {   \foreach \z in {\steppingz,\secondz,...,\dimz}
        {   \pgfmathsetmacro{\lowx}{(\x-\steppingx)}
            \pgfmathsetmacro{\lowz}{(\z-\steppingz)}
            \filldraw[fill=green,draw=red] (\lowx,\dimy,\lowz) -- (\lowx,\dimy,\z) -- (\x,\dimy,\z) -- (\x,\dimy,\lowz) -- cycle;
        }
    }
    \foreach \y in {\steppingy,\secondy,...,\dimy}
    {   \foreach \z in {\steppingz,\secondz,...,\dimz}
        {   \pgfmathsetmacro{\lowy}{(\y-\steppingy)}
            \pgfmathsetmacro{\lowz}{(\z-\steppingz)}
            \filldraw[fill=red!50!blue,draw=yellow] (\dimx,\lowy,\lowz) -- (\dimx,\lowy,\z) -- (\dimx,\y,\z) -- (\dimx,\y,\lowz) -- cycle;
        }
    }
    \end{scope}

    % Write parameters to log file, just for checking       
%   \typeout{=============================}
%   \typeout{*****************************}
%   \typeout{tikzcuboid shiftx = \tikzcuboid@shiftx}
%   \typeout{tikzcuboid shifty = \tikzcuboid@shifty}
%   \typeout{tikzcuboid dimx = \tikzcuboid@dimx}
%   \typeout{tikzcuboid dimy = \tikzcuboid@dimy}
%   \typeout{tikzcuboid dimz = \tikzcuboid@dimz}
%   \typeout{tikzcuboid scale = \tikzcuboid@scale}
%   \typeout{tikzcuboid densityx = \tikzcuboid@densityx}
%   \typeout{tikzcuboid densityy = \tikzcuboid@densityy}
%   \typeout{tikzcuboid densityz = \tikzcuboid@densityz}
%   \typeout{tikzcuboid rotation = \tikzcuboid@rotation}
%   \typeout{tikzcuboid anglex = \tikzcuboid@anglex}
%   \typeout{tikzcuboid angley = \tikzcuboid@angley}
%   \typeout{tikzcuboid anglez = \tikzcuboid@anglez}
%   \typeout{tikzcuboid scalex = \tikzcuboid@scalex}
%   \typeout{tikzcuboid scaley = \tikzcuboid@scaley}
%   \typeout{tikzcuboid scalez = \tikzcuboid@scalez}
%   \typeout{tikzcuboid linefront = \tikzcuboid@linefront}
%   \typeout{tikzcuboid linetop = \tikzcuboid@linetop}
%   \typeout{tikzcuboid lineright = \tikzcuboid@lineright}
%   \typeout{tikzcuboid fillfront = \tikzcuboid@fillfront}
%   \typeout{tikzcuboid filltop = \tikzcuboid@filltop}
%   \typeout{tikzcuboid fillright = \tikzcuboid@fillright}
%   \typeout{tikzcuboid newcoords = \tikzcuboid@newcoords}
%   \typeout{tikzcuboid filled = \tikzcuboid@filled}
%   \typeout{tikzcuboid shaded = \tikzcuboid@shaded}
%   \typeout{*****************************}
%   \typeout{=============================}
}

\makeatother


\begin{document}

\begin{tikzpicture}
    \tikzcuboid{shiftx=0cm,%
        shifty=0cm,%
        scale=1.00,%
        rotation=30,%
        densityx=1,%
        densityy=2,%
        densityz=3%
    }
    \tikzcuboid{%
        shiftx=0cm,%
        shifty=8cm,%
        scale=1.00,%
        rotation=60,%
        densityx=3,%
        densityy=2,%
        densityz=5%
    }
    \tikzcuboid{%
        shiftx=8cm,%
        shifty=8cm,%
        scale=1.00,%
        rotation=45,%
        densityx=0.5,%
        densityy=1,%
        densityz=2%
    }
    \tikzcuboid{%
        shiftx=8cm,%
        shifty=0cm,%
        scale=1.00,%
        rotation=75,%
        densityx=2,%
        densityy=7,%
        densityz=2%
    }
\end{tikzpicture}

\end{document}

% https://tex.stackexchange.com/questions/29877/need-help-creating-a-3d-cube-from-a-2d-set-of-nodes-in-tikz
% \documentclass{article}
% arr: add comments; reindent
%
\documentclass[parskip]{scrartcl}
\usepackage[margin=10mm,landscape]{geometry}
\usepackage{tikz}

\newif\ifcuboidshade
\newif\ifcuboidemphedge

\tikzset{
  cuboid/.is family,
  cuboid,
  shiftx/.initial=0,
  shifty/.initial=0,
  dimx/.initial=3,
  dimy/.initial=3,
  dimz/.initial=3,
  scale/.initial=1,
  densityx/.initial=1,
  densityy/.initial=1,
  densityz/.initial=1,
  rotation/.initial=0,
  anglex/.initial=0,
  angley/.initial=90,
  anglez/.initial=225,
  scalex/.initial=1,
  scaley/.initial=1,
  scalez/.initial=0.5,
  front/.style={draw=black,fill=white},
  top/.style={draw=black,fill=white},
  right/.style={draw=black,fill=white},
  shade/.is if=cuboidshade,
  shadecolordark/.initial=black,
  shadecolorlight/.initial=white,
  shadeopacity/.initial=0.15,
  shadesamples/.initial=16,
  emphedge/.is if=cuboidemphedge,
  emphstyle/.style={thick},
}

\newcommand{\tikzcuboidkey}[1]{\pgfkeysvalueof{/tikz/cuboid/#1}}

% Commands
\newcommand{\tikzcuboid}[1]{
    \tikzset{cuboid,#1} % Process Keys passed to command
    \pgfmathsetlengthmacro{\vectorxx}{\tikzcuboidkey{scalex}*cos(\tikzcuboidkey{anglex})*28.452756}
    \pgfmathsetlengthmacro{\vectorxy}{\tikzcuboidkey{scalex}*sin(\tikzcuboidkey{anglex})*28.452756}
    \pgfmathsetlengthmacro{\vectoryx}{\tikzcuboidkey{scaley}*cos(\tikzcuboidkey{angley})*28.452756}
    \pgfmathsetlengthmacro{\vectoryy}{\tikzcuboidkey{scaley}*sin(\tikzcuboidkey{angley})*28.452756}
    \pgfmathsetlengthmacro{\vectorzx}{\tikzcuboidkey{scalez}*cos(\tikzcuboidkey{anglez})*28.452756}
    \pgfmathsetlengthmacro{\vectorzy}{\tikzcuboidkey{scalez}*sin(\tikzcuboidkey{anglez})*28.452756}
    \begin{scope}[xshift=\tikzcuboidkey{shiftx}, yshift=\tikzcuboidkey{shifty}, scale=\tikzcuboidkey{scale}, rotate=\tikzcuboidkey{rotation}, x={(\vectorxx,\vectorxy)}, y={(\vectoryx,\vectoryy)}, z={(\vectorzx,\vectorzy)}]
      \pgfmathsetmacro{\steppingx}{1/\tikzcuboidkey{densityx}}
    \pgfmathsetmacro{\steppingy}{1/\tikzcuboidkey{densityy}}
    \pgfmathsetmacro{\steppingz}{1/\tikzcuboidkey{densityz}}
    \newcommand{\dimx}{\tikzcuboidkey{dimx}}
    \newcommand{\dimy}{\tikzcuboidkey{dimy}}
    \newcommand{\dimz}{\tikzcuboidkey{dimz}}
    \pgfmathsetmacro{\secondx}{2*\steppingx}
    \pgfmathsetmacro{\secondy}{2*\steppingy}
    \pgfmathsetmacro{\secondz}{2*\steppingz}
    \foreach \x in {\steppingx,\secondx,...,\dimx}
    { \foreach \y in {\steppingy,\secondy,...,\dimy}
      {   \pgfmathsetmacro{\lowx}{(\x-\steppingx)}
        \pgfmathsetmacro{\lowy}{(\y-\steppingy)}
        \filldraw[cuboid/front] (\lowx,\lowy,\dimz) -- (\lowx,\y,\dimz) -- (\x,\y,\dimz) -- (\x,\lowy,\dimz) -- cycle;
      }
      }
    \foreach \x in {\steppingx,\secondx,...,\dimx}
    { \foreach \z in {\steppingz,\secondz,...,\dimz}
      {   \pgfmathsetmacro{\lowx}{(\x-\steppingx)}
        \pgfmathsetmacro{\lowz}{(\z-\steppingz)}
        \filldraw[cuboid/top] (\lowx,\dimy,\lowz) -- (\lowx,\dimy,\z) -- (\x,\dimy,\z) -- (\x,\dimy,\lowz) -- cycle;
          }
      }
      \foreach \y in {\steppingy,\secondy,...,\dimy}
    { \foreach \z in {\steppingz,\secondz,...,\dimz}
      {   \pgfmathsetmacro{\lowy}{(\y-\steppingy)}
        \pgfmathsetmacro{\lowz}{(\z-\steppingz)}
        \filldraw[cuboid/right] (\dimx,\lowy,\lowz) -- (\dimx,\lowy,\z) -- (\dimx,\y,\z) -- (\dimx,\y,\lowz) -- cycle;
      }
    }
    \ifcuboidemphedge
      \draw[cuboid/emphstyle] (0,\dimy,0) -- (\dimx,\dimy,0) -- (\dimx,\dimy,\dimz) -- (0,\dimy,\dimz) -- cycle;%
      \draw[cuboid/emphstyle] (0,\dimy,\dimz) -- (0,0,\dimz) -- (\dimx,0,\dimz) -- (\dimx,\dimy,\dimz);%
      \draw[cuboid/emphstyle] (\dimx,\dimy,0) -- (\dimx,0,0) -- (\dimx,0,\dimz);%
      \fi

      \ifcuboidshade
      \pgfmathsetmacro{\cstepx}{\dimx/\tikzcuboidkey{shadesamples}}
      \pgfmathsetmacro{\cstepy}{\dimy/\tikzcuboidkey{shadesamples}}
      \pgfmathsetmacro{\cstepz}{\dimz/\tikzcuboidkey{shadesamples}}
      \foreach \s in {1,...,\tikzcuboidkey{shadesamples}}
      {   \pgfmathsetmacro{\lows}{\s-1}
          \pgfmathsetmacro{\cpercent}{(\lows)/(\tikzcuboidkey{shadesamples}-1)*100}
          \fill[opacity=\tikzcuboidkey{shadeopacity},color=\tikzcuboidkey{shadecolorlight}!\cpercent!\tikzcuboidkey{shadecolordark}] (0,\s*\cstepy,\dimz) -- (\s*\cstepx,\s*\cstepy,\dimz) -- (\s*\cstepx,0,\dimz) -- (\lows*\cstepx,0,\dimz) -- (\lows*\cstepx,\lows*\cstepy,\dimz) -- (0,\lows*\cstepy,\dimz) -- cycle;
          \fill[opacity=\tikzcuboidkey{shadeopacity},color=\tikzcuboidkey{shadecolorlight}!\cpercent!\tikzcuboidkey{shadecolordark}] (0,\dimy,\s*\cstepz) -- (\s*\cstepx,\dimy,\s*\cstepz) -- (\s*\cstepx,\dimy,0) -- (\lows*\cstepx,\dimy,0) -- (\lows*\cstepx,\dimy,\lows*\cstepz) -- (0,\dimy,\lows*\cstepz) -- cycle;
          \fill[opacity=\tikzcuboidkey{shadeopacity},color=\tikzcuboidkey{shadecolorlight}!\cpercent!\tikzcuboidkey{shadecolordark}] (\dimx,0,\s*\cstepz) -- (\dimx,\s*\cstepy,\s*\cstepz) -- (\dimx,\s*\cstepy,0) -- (\dimx,\lows*\cstepy,0) -- (\dimx,\lows*\cstepy,\lows*\cstepz) -- (\dimx,0,\lows*\cstepz) -- cycle;
      }
      \fi 

    \end{scope}
}

\makeatother

\begin{document}


\begin{tikzpicture}
    % cuboid #1
    \tikzcuboid{%
      shiftx=0cm,%
      shifty=8cm,%
      scale=1.00,%
      rotation=0,%
      densityx=2,%
      densityy=2,%
      densityz=2,%
      dimx=3,%
      dimy=3,%
      dimz=3,%
      scalex=1,%
      scaley=1,%
      scalez=1,%
      anglex=-30,%
      angley=90,%
      anglez=210,%
      front/.style={draw=green!50!black,fill=green!50!white},%
      top/.style={draw=green!50!black,fill=green!50!white},%
      right/.style={draw=green!50!black,fill=green!50!white},%
      emphedge,%
      emphstyle/.style={line width=1pt, green!12!black,densely dashed},
      shade,%
      shadesamples=64,%
      shadeopacity=0.15,%
    }
    \tikzcuboid{%
      % cuboid #2
      shiftx=8cm,%
      shifty=8cm,%
      shadeopacity=0.30,%
    }   
    \tikzcuboid{%
      % cuboid #3
      shiftx=16cm,%
      shifty=8cm,%
      shadeopacity=0.60,%
    }   
    \tikzcuboid{%
      % cuboid #4
      shiftx=0cm,%
      shifty=0cm,%
      scale=1.00,%
      rotation=0,%
      densityx=1,%
      densityy=1,%
      densityz=1,%
      dimx=4,%
      dimy=4,%
      dimz=4,%
      front/.style={draw=blue!75!black,fill=blue!25!white},%
      right/.style={draw=blue!25!black,fill=blue!75!white},%
      top/.style={draw=blue!50!black,fill=blue!50!white},%
      anglex=-7,%
      angley=90,%
      anglez=221.5,%
      scalex=1,%
      scaley=1,%
      scalez=0.5,%
      emphedge=false,%
      shade,%
      shadeopacity=0.15,%
    }
    \tikzcuboid{%
      % cuboid #5
      shiftx=8cm,%
      shifty=0cm,%
      shadeopacity=0.30,%
    }
    \tikzcuboid{%
      % cuboid #6
      shiftx=16cm,%
      shifty=0cm,%
      shadeopacity=0.60,%
    }
\end{tikzpicture}

\end{document}

\documentclass[landscape]{article}
\usepackage{tikz}
% arr: new page size; clean up redundant packages

%%%<
\usepackage{verbatim}
\usepackage[active,tightpage]{preview}
\PreviewEnvironment{tikzpicture}
\setlength\PreviewBorder{5pt}%
%%%>

\usepackage{tikz-3dplot}

\begin{document}

\begin{figure}
	\centering
	\tdplotsetmaincoords{70}{120}

	\begin{tikzpicture}[tdplot_main_coords][scale=0.75]
		\tikzstyle{every node}=[font=\small]
		\draw[thick,-latex] (0,0,0) -- (6,0,0) node[anchor=north east]{$x$};
		\draw[thick,-latex] (0,0,0) -- (0,6,0) node[anchor=north west]{$y$};
		\draw[thick,-latex] (0,0,0) -- (0,0,6) node[anchor=south]{$z$};
		\draw [thick](0,0,0) circle (3);
		\draw [thick](0,0,4) circle (3);
		\draw [thick](1.9,-2.35,0) -- (1.9,-2.35,4) node[midway, left]{$r=r_1$ surface};
		\draw [thick](-1.9,2.35,0) -- (-1.9,2.35,4);
		\filldraw[fill=orange, nearly transparent] (-4,-4,4) -- (4,-4,4) --  (4,5,4) -- (-4,5,4) -- (-4,-4,4);
		\filldraw[fill=blue, nearly transparent] (0,0,4) -- (5.2,6,4) --  (5.2,6,0) -- (0,0,0) -- (0,0,4);
		\filldraw [color=blue](2,2.25,4) circle (0.075cm) ;
		\draw (-4,5,4) node[anchor=south]{$z=z_1$ plane};
		\draw (5.2,6,0) node[anchor=south west]{$\phi=\phi_1$ plane};
		\node at (1.8,1,4)  { $P_1(r_1,\phi_1,z_1)$};
		\draw[ultra thick,-latex](2,2.25,4) -- (3,3.45,4) node[anchor=north] {$\mathbf{a}_r$};
		\draw[ultra thick,-latex](2,2.25,4) -- (1,2.5,4) node[anchor=north west] {$\mathbf{a}_\phi$};
		\draw[ultra thick,-latex](2,2.25,4) -- (2,2.25,4.75) node[anchor=north west] {$\mathbf{a}_z$};
		\draw [thick,->](4,0,0) arc (0:45:4 and 4.5);
		\draw (3.6,2,0) node[anchor=north] {$\phi_1$};
		\draw[ultra thick,-latex](0,0,0) -- (2,2.35,0);
		\draw (1,1,0) node[anchor=north] {$r_1$};
		\draw [ultra thick] (2,2.25,4)--(1.95,2.25,0);
		
		\draw[ultra thick](0.1,0,4) -- (-0.1,0,4) node[anchor=south west] {$z_1$};
	\end{tikzpicture}
\end{figure}
\end{document}

% https://github.com/MartinThoma/LaTeX-examples/blob/master/tikz/3d-gradient-colored/3d-gradient-colored.tex
% arr: reindenting
\documentclass[varwidth=true, border=2pt]{standalone}

\usepackage[usenames,dvipsnames]{xcolor}
\usepackage{pgfplots}

\pgfplotsset{compat=1.13}
\usetikzlibrary{arrows.meta}

\begin{document}
\pgfplotsset{
    colormap={whitered}{
        color(0.000cm)=(blue!50!black);
        color(0.125cm)=(blue);
        color(0.250cm)=(SkyBlue);
        color(0.375cm)=(SkyBlue);
        color(0.500cm)=(SpringGreen);
        color(0.625cm)=(yellow);
        color(0.750cm)=(yellow);
        color(0.875cm)=(red);
        color(1.000cm)=(red!50!black)
    }
}

\begin{tikzpicture}
    \begin{axis}[
        domain=-2:2,
        view={0}{90},
        axis background/.style={fill=white},
        xmin=-2, xmax=2,
        ymin=-2, ymax=2,
        axis equal image,
        point meta rel=per plot
    ]
        \addplot3
            [surf,
            samples=50,
            shader=interp,
            colormap name=whitered
            ]
                {x/exp(x^2+y^2)};
        % \addplot3[contour gnuplot={number=15, labels=false},
        %           very thick,
        %           samples=30]
        %         {x/exp(x^2+y^2)};
        \addplot3
            [blue,
            point meta={
                sqrt(
                    ((1-2*x^2)*exp(-x^2-y^2))^2+
                    (-2*x*y*exp(-x^2-y^2))^2
                )
            },
            quiver={
                    u={(1-2*x^2)*exp(-x^2-y^2)},
                    v={-2*x*y*exp(-x^2-y^2)},
                    scale arrows=0.3,
                    every arrow/.append style={%
                        -{Latex[scale length={max(0.01,\pgfplotspointmetatransformed/1000)}]},
                        },
            },
            samples=15]
                {x/exp(x^2+y^2)};
    \end{axis}
\end{tikzpicture}
\end{document}

% https://github.com/MartinThoma/LaTeX-examples/blob/master/tikz/hypersurface-3/hypersurface-3.tex
\documentclass{article}

\usepackage[pdftex,active,tightpage]{preview}
\setlength\PreviewBorder{2mm}
\usepackage{pgfplots}
\usepackage{units}

\pgfplotsset{compat=1.3}% <-- moves axis labels near ticklabels
                        % (respects tick label widths)
\usepackage{tikz}
\usetikzlibrary{arrows, positioning, calc, intersections, decorations.markings}

\usepackage{xcolor}
\definecolor{horizontalLineColor}{HTML}{008000}
\definecolor{verticalLineColor}{HTML}{FF0000}


\begin{document}

% Define this as a command to ensure that it is same in both cases
\newcommand*{\ShowIntersection}[2]{
\fill
    [name intersections={of=#1 and #2, name=i, total=\t}]
    [red, opacity=1, every node/.style={above left, black, opacity=1}]
    \foreach \s in {1,...,\t}{(i-\s) circle (2pt)
        node [above left] {\s}};
}

\begin{preview}
\begin{tikzpicture}
    \begin{axis}[
        grid=both,
        minor tick num=1,
        xlabel=$x$,
        ylabel=$y$,
        zlabel=$z$,
        %label distance=0mm,
        %width=8cm, height=7cm,     % size of the image
        axis lines=left,
        %tick style={draw=none},
        %xticklabels={,,},
        %yticklabels={,,}
    ]
      \addplot3[surf, colormap name=viridis] {-3/25*x*x+1/25*y*y};
    \end{axis}
\end{tikzpicture}
\end{preview}

\end{document}

% https://wiki.physik.uzh.ch/cms/latex:tikz:jet_cones
\documentclass{standalone}

\usepackage{amsmath} % for \dfrac
\usepackage{tikz}
\usepackage{tikz-3dplot}

\tikzset{>=latex} % for LaTeX arrow head
\usetikzlibrary{decorations.pathmorphing} % for snake

% colors
\definecolor{mylightred}{RGB}{255,200,200}
\definecolor{myblue}{RGB}{172,188,63}
\definecolor{mylightgreen}{RGB}{150,220,150}

% split figures into pages
\usepackage[active,tightpage]{preview}
\PreviewEnvironment{tikzpicture}
\setlength\PreviewBorder{1pt}%

% draw two cones
\begin{document}

% BOOSTED TAU
\begin{tikzpicture}
	% AK8 variables
	\def\x{2.4}
	\def\y{3.5}
	\def\R{\x+0.02}
	\def\yc{\y+0.08}
	\def\e{0.6}
	
	% AK8 cone
	\shade[right color=white,left color=blue,opacity=0.2]
	(-\x,\y) -- (-\x,\yc) arc (180:360:{\R} and \e) -- (\x,\y) -- (0,0) -- cycle;
	%\shade[right color=white,left color=blue,opacity=0.2]
	%(0,\yc) circle ({\R} and \e);
	%(-\x,\yc) -- ( \x,\yc) arc ( -2:182:{\R} and \e) -- (\x,\yc) -- (0,0) -- cycle;
	\draw[fill=blue,opacity=0.2]
	(0,\yc) circle ({\R} and \e);
	\draw
	(-\x,\y) -- (0,0) -- (\x,\y);
	\draw
	(0,\yc) circle ({\R} and \e);
	
	% AK4 variables
	\def\x{1.0}
	\def\y{4.0}
	\def\R{\x+0.005}
	\def\yc{\y+0.04}
	\def\e{0.4}
	
	% AK4 cone 1
	\begin{scope}[rotate=12]
		\shade[right color=white,left color=green,opacity=0.3]
		(-\x,\yc) -- (-\x,\yc) arc (180:360:{\R} and \e) -- (\x,\yc) -- (0,0) -- cycle;
		\draw[fill=green,opacity=0.2]
		(0,\yc) circle ({\R} and \e);
		\draw
		(-\x,\y) -- (0,0) -- (\x,\y);
		\draw
		(0,\yc) circle ({\R} and \e);
	\end{scope}
	
	% AK4 cone 2
	\begin{scope}[rotate=-10]
		\shade[right color=white,left color=red,opacity=0.3]
		(-\x,\yc) -- (-\x,\yc) arc (180:360:{\R} and \e) -- (\x,\yc) -- (0,0) -- cycle;
		\draw[fill=red,opacity=0.2]
		(0,\yc) circle ({\R} and \e);
		\draw
		(-\x,\y) -- (0,0) -- (\x,\y);
		\draw
		(0,\yc) circle ({\R} and \e);
	\end{scope}
\end{tikzpicture}

% TikZ code
% 2D CONE
\begin{tikzpicture}%,scale=0.85
	% cone variables
	\def\x{2.0}
	\def\y{4.0}
	\def\R{\x}
	\def\yc{\y+0.02}
	\def\e{0.4}
	
	% cone shades + frame
	\shade[right color=white,left color=mylightgreen,opacity=0.3]
	(-\x,\yc) -- (-2,4) arc (180:360:{\R} and \e) -- (\x,\yc) -- (0,0) -- cycle;
	\draw[fill=green,opacity=0.2]
	(0,\yc) circle ({\R} and \e);
	\draw
	(-\x,\y) -- (0,0) -- (\x,\y);
	\draw
	(0,\yc) circle ({\R} and \e);
	
	% tracks
	\draw[thick]
	(0,0) arc (320:360:-3 and 6.0); %node[above] {1};
	\draw[thick]
	(0,0) arc (-70:  0:0.8 and 3.5); %node[above] {2};
	\draw[thick]
	(0,0) arc (  0: 70:0.9 and 4.5); %node[above] {3};
	\draw[thick]
	(0,0) arc (180:140:2 and 6.0); %node[above] {4};
	\draw[thick,dashed]
	(0,0) -- (1,4.6);
\end{tikzpicture}
\end{document}

\documentclass[margin=10pt]{standalone}
\usepackage{tikz}
\usepackage{tikz-3dplot}
\begin{document}

\tdplotsetmaincoords{70}{70}
\begin{tikzpicture}[scale=3,tdplot_main_coords]

\fill[draw=red, fill=red!20, variable=\z,domain=-.5:1,samples=200] 
    (0,0,-.5) plot (0,{sin(\z*pi r*4)/10},\z)
    -- (0,1,1)
    -- (0,1,-0.5)
    -- cycle;

\draw[thick,->] (0,-0.2,0) -- (0,1.2,0) node[anchor=north west]{$x$};
\draw[thick,->] (0,0,-0.5) -- (0,0,1.2) node[anchor=south]{$z$};
\draw[thick,->] (-0.5,0,0) -- (1.2,0,0) node[anchor=north east]{$y$};
\end{tikzpicture}
\end{document}

% http://www.texample.net/media/tikz/examples/TEX/seismic-focal-mechanism-in-3d-view.tex
% Title: Seismic focal mechanism in 3D view.
% Author: Cyril Langlois
% Source:  Jacques Duma
% Site: http://math.et.info.free.fr/TikZ/index.html
%
% Adaptation for LaTeX of a figure proposed in P. Shearer's book 'Introduction
% to Seismology'.
%
% It shows the focal sphere with the fault plane and auxiliary plane (which can
% not be discriminate), limiting compression and dilatation quadrants, the first
% movement of the rock through the sphere, and the Pression and Tension axis.
%
% The figure is based on the sphere drawing's code proposed by J. Dumas in is
% book 'Tikz pour l'impatient', available online.

\documentclass[11pt]{article}
\usepackage{tikz}
\usepackage{tikz-3dplot}
%%%<
\usepackage{verbatim}
\usepackage[active,tightpage]{preview}
\PreviewEnvironment{tikzpicture}
\setlength\PreviewBorder{5pt}%
%%%>

\begin{comment}
:Title: Seismic focal mechanism in 3D view.
:Tags: 3D; Earth Sciences ; Geophysics; Seismology
:Author: Cyril Langlois
:Source: http://math.et.info.free.fr/TikZ/index.html

Adaptation for LaTeX of a figure proposed in P. Shearer's book 'Introduction to Seismology'. 

It shows the focal sphere with the fault plane and auxiliary plane (which can
not be discriminate), limiting compression and dilatation quadrants, the first
movement of the rock through the sphere, and the Pression and Tension axis.

The figure is based on the sphere drawing's code proposed by J. Dumas in is
book `Tikz pour l'impatient <http://math.et.info.free.fr/TikZ/>`_, available online.

\end{comment}

%%%%%%%%%%%
%% helper macros
%: Styles for XYZ-Coordinate Systems
%: isometric  South West : X , South East : Y , North : Z
\tikzset{isometricXYZ/.style={x={(-0.866cm,-0.5cm)}, y={(0.866cm,-0.5cm)}, z={(0cm,1cm)}}}

%: isometric South West : Z , South East : X , North : Y
\tikzset{isometricZXY/.style={x={(0.866cm,-0.5cm)}, y={(0cm,1cm)}, z={(-0.866cm,-0.5cm)}}}

%: isometric South West : Y , South East : Z , North : X
\tikzset{isometricYZX/.style={x={(0cm,1cm)}, y={(-0.866cm,-0.5cm)}, z={(0.866cm,-0.5cm)}}}

%% document-wide tikz options and styles
\begin{document}
\begin{tikzpicture} [scale=4, isometricZXY, line join=round,
        opacity=.75, text opacity=1.0,%
        >=latex,
        inner sep=0pt,%
        outer sep=2pt,%
    ]
    \def\h{5}

    \newcommand{\quadrant}[2]{
        \foreach \t in {#1} \foreach \f in {175,165,...,5}
            \draw [fill=#2]
                  ({sin(\f - \h)*cos(\t - \h)}, {sin(\f - \h)*sin(\t - \h)}, {cos(\f - \h)})
               -- ({sin(\f - \h)*cos(\t + \h)}, {sin(\f - \h)*sin(\t + \h)}, {cos(\f - \h)})
               -- ({sin(\f + \h)*cos(\t + \h)}, {sin(\f + \h)*sin(\t + \h)}, {cos(\f + \h)})
               -- ({sin(\f + \h)*cos(\t - \h)}, {sin(\f + \h)*sin(\t - \h)}, {cos(\f + \h)})
               -- cycle;
    }

    %Quadrants
    \quadrant{220,230,...,300}{black}
    \quadrant{-60,-50,...,20}{white}
    \quadrant{30,40,...,120}{black}
    \quadrant{130,140,...,210}{none}

    %Movement arrows
    \foreach \t in {225,235,...,295}
        \foreach \f in {50,40,...,0}
            \draw [red, opacity=1.0, ->, thick]
                ({sin(\f - \h)*cos(\t - \h)}, {sin(\f - \h)*sin(\t - \h)}, {cos(\f - \h)})
                -- ({(1 + 0.2*cos(90 - \f))*sin(\f - \h)*cos(\t - \h)},
                    {(1 + 0.2*cos(90 - \f))*sin(\f - \h)*sin(\t - \h)},
                    {(1 + 0.2*cos(90 - \f))*cos(\f - \h)});

    \foreach \t in {125,135,...,205}
        \foreach \f in {110,100,...,0}
            \draw [black, ->, thick]
                ({(1 + 0.2*cos(90 - \f))*sin(\f - \h)*cos(\t - \h)},
                 {(1 + 0.2*cos(90 - \f))*sin(\f - \h)*sin(\t - \h)},
                 {(1 + 0.2*cos(90 - \f))*cos(\f - \h)})
                -- ({sin(\f - \h)*cos(\t - \h)},{sin(\f - \h)*sin(\t - \h)},{cos(\f - \h)});
    \foreach \t in {35,45,...,115}
        \foreach \f in {130,120,...,0}
            \draw [red, opacity=1.0 ,->, thick]
                ({sin(\f - \h)*cos(\t - \h)}, {sin(\f - \h)*sin(\t - \h)}, {cos(\f - \h)})
                -- ({(1 + 0.2*cos(90 - \f))*sin(\f - \h)*cos(\t - \h)},
                    {(1 + 0.2*cos(90 - \f))*sin(\f - \h)*sin(\t - \h)},
                    {(1 + 0.2*cos(90 - \f))*cos(\f - \h)});

    \foreach \t in {-55,-45,...,25}
        \foreach \f in {130,120,...,0}
            \draw [black, ->, thick]
                ({(1 + 0.2*cos(90 - \f))*sin(\f - \h)*cos(\t - \h)},
                 {(1 + 0.2*cos(90 - \f))*sin(\f - \h)*sin(\t - \h)},
                 {(1 + 0.2*cos(90 - \f))*cos(\f - \h)})
              -- ({sin(\f - \h)*cos(\t - \h)},{sin(\f - \h)*sin(\t - \h)},{cos(\f - \h)});

    %Annotations
    \path ({1.5*sin(100)*cos(75)}, {1.5*sin(100)*sin(75)}, {1.5*cos(100)}) node [right] {Compression};
    \path ({1.5*sin(70)*cos(-15)}, {1.5*sin(70)*sin(-15)}, {1.5*cos(70)})  node [right] {Dilatation};
    \path ({1.25*sin(50)*cos(165)},{1.25*sin(50)*sin(165)},{1.25*cos(50)}) node [left]  {Dilatation};
    \path ({1.25*sin(30)*cos(255)},{1.25*sin(30)*sin(255)},{1.25*cos(30)}) node [left]  {Compression};

    %P and T axis
    \begin{scope}[ultra thick]
        \draw[->] ({1.75*sin(90)*cos(75)}, {1.75*sin(90)*sin(75)}, {1.75*cos(90)})
            -- ({2*sin(90)*cos(75)},{2*sin(90)*sin(75)},{2*cos(90)}) node [above] {T-axis};
        \draw[->] ({1.75*sin(90)*cos(255)},{1.75*sin(90)*sin(255)},{1.75*cos(90)})
            -- ({2*sin(90)*cos(255)},{2*sin(90)*sin(255)},{2*cos(90)}) node [below] {T-axis};
        \draw[<-] ({1.5*sin(90)*cos(-15)}, {1.5*sin(90)*sin(-15)}, {1.5*cos(90)})
            -- ({1.75*sin(90)*cos(-15)},{1.75*sin(90)*sin(-15)},{1.75*cos(90)}) node [right] {P-axis};
        \draw[<-] ({1.5*sin(90)*cos(165)}, {1.5*sin(90)*sin(165)}, {1.5*cos(90)})
            -- ({1.75*sin(90)*cos(165)},{1.75*sin(90)*sin(165)},{1.75*cos(90)}) node [left] {P-axis};
    \end{scope}

    % Label
    \node [anchor=north, yshift=-2mm] at (current bounding box.south)
        {Seismic focal mechanism and Pression-Tension axis.};
\end{tikzpicture}
\end{document}

% https://github.com/MartinThoma/LaTeX-examples/blob/master/tikz/solid-of-revolution/solid-of-revolution.tex
% Author: Marco Miani
\documentclass[varwidth=true, border=2pt]{standalone}

\usepackage{pgfplots}
\pgfplotsset{compat=1.9}

\begin{document}
\pgfplotsset{
    colormap={whitered}{
        color(0cm)=(white);
        color(1cm)=(orange!75!red)
    }
    %colormap={color}{color(0cm)=(white); color(1cm)=(blue)}
}

\begin{tikzpicture}
    \begin{axis}[view={60}{30}]
        \addplot3[surf,
        samples=50,
        domain=1:2,y domain=0:2*pi,
        z buffer=sort]
        %({(2 + tan(deg(y)))*cos((deg(x)))}, {(2 + cos(x)) * sin(x)}, {x});
        ({x * cos(deg(y))}, {x * sin(deg(y))}, {1/x});
    \end{axis}
\end{tikzpicture}
\end{document}

% 3d-torus.tex
\documentclass[border=5pt]{standalone}
%%%<
\usepackage{verbatim}
%%%>
\usepackage{pgfplots}
\pgfplotsset{width=7cm,compat=1.8}

\begin{comment}
:Title: Torus
:Tags: Surface plots
:Author: cmhughes
:Slug: torus

For drawing a torus, we can parametrize the surface as (for example)

x(t,s) = (2+cos(t))*cos(s+pi/2) 
y(t,s) = (2+cos(t))*sin(s+pi/2) 
z(t,s) = sin(t)

where both t and s take values on [0,2pi].

This code was written by cmhughes on TeX.SE.
\end{comment}

\begin{document}
\begin{tikzpicture}
  \begin{axis}
     \addplot3[
         surf,
         colormap/cool,
         samples=20,
         domain=0:2*pi,
         y domain=0:2*pi,
         z buffer=sort
       ]
       ( {(2+cos(deg(x)))*cos(deg(y+pi/2))}, 
         {(2+cos(deg(x)))*sin(deg(y+pi/2))}, 
         {sin(deg(x))}
       );
  \end{axis}
\end{tikzpicture}
\end{document}

% Artificial Intelligence Agent Contributors
% Drawn by Alfonso R. Reyes
% November 27, 2020
% Personal interpretation of "Artificial Intelligence: A Modern Approach" by Peter Norvig and Stuart Russell
% Original diagram: https://github.com/FriendlyUser/LatexDiagrams
\documentclass[border=5pt]{standalone}
\usepackage{xcolor}
\usepackage{ulem}


	\definecolor{ocre}{HTML}{800000}
	\definecolor{sky}{HTML}{C6D9F1}
	\definecolor{skybox}{HTML}{5F86B3}

\usepackage{tikz}
\usepackage{pgfmath}
\usetikzlibrary{decorations.text, arrows.meta,calc,shadows.blur,shadings}

\renewcommand*\familydefault{\sfdefault} % Set font to serif family

% arctext from Andrew code with modifications:
%Variables: 1: ID, 2:Style 3:box height 4: Radious 5:start-angl 6:end-angl 7:text {format along path} 
\def\arctext[#1][#2][#3](#4)(#5)(#6)#7{

\draw[#2] (#5:#4cm+#3) coordinate (above #1) arc (#5:#6:#4cm+#3)
             -- (#6:#4) coordinate (right #1) -- (#6:#4cm-#3) coordinate (below right #1) arc (#6:#5:#4cm-#3) coordinate (below #1)
             -- (#5:#4) coordinate (left #1) -- cycle;
            \def\a#1{#4cm+#3}
            \def\b#1{#4cm-#3}
\path[
    decoration={
        raise = -0.5ex, % Controls relavite text height position.
        text  along path,
        text = {#7},
        text align = center,        
    },
    decorate
    ]
    (#5:#4) arc (#5:#6:#4);
}

% arcarrow, this is mine, for beerware purpose...
% Function: Draw an arrow from arctex coordinate specific nodes to another 
% Arrow start at the start of arctext box and could be shifted to change the position
% to avoid go over another box.
% Var: 1:Start coordinate 2:End coordinate 3:angle to shift from acrtext box  
\def\arcarrow(#1)(#2)[#3]{
    \draw[very thick,->,>=latex,black!60] 
        let \p1 = (#1), \p2 = (#2), % To access cartesian coordinates x, and y.
            \n1 = {veclen(\x1,\y1)}, % Distance from the origin
            \n2 = {veclen(\x2,\y2)}, % Distance from the origin
            \n3 = {atan2(\y1,\x1)} % Angle where acrtext starts.
        in (\n3-#3: \n1) -- (\n3-#3: \n2); % Draw the arrow.
}


\begin{document}
\begin{tikzpicture}[
	    % Environment Cfg
	    font=\sf    \scriptsize,
	    % Styles
	    myarrow/.style={
	        very thick,
	        -latex,
            black!60,            
	    },
	    Center/.style ={
	        circle,
	        fill=ocre,
	        text=white,
	        align=center,
	        font =\footnotesize\bf,
	        inner sep=1pt,          
	    },
	    RedArc/.style ={
	        color=black,
	        thick,
	        fill=ocre,
	        blur shadow, 
	    },
	    SkyArc/.style ={
	        color=skybox,
	        thick,
	        fill=sky,
	        blur shadow, 
	    },
    ]

    % Drawing the center for AI
    \node[Center](AI) at (0,0) { Artificial \\ Intelligence \\(AI)\\ Agent};
    \coordinate (AROUND) at (0:1.2); 

    % Drawing the Text Arcs
    % Format: \Arctext[ID][box-style][box-height](radious)(start-angl)(end-angl){|text-styles| Text}
    
	% Machine Learning
    \arctext[ML][RedArc][8pt](2.75)(140)(75){|\footnotesize\bf\color{white}| Machine Learning};
	\arctext[REIN][SkyArc][5pt](3.50)(140)(75){|\scriptsize\color{black}| Reinforcement Learning};
	\arctext[KNOW][SkyArc][5pt](4.00)(110)(75){|\scriptsize| Knowledge L.};
	\arctext[SUPL][SkyArc][5pt](4.00)(140)(112){|\scriptsize| Supervised L.};
	\arctext[PROB][SkyArc][5pt](4.50)(140)(109){|\scriptsize\color{black}| Probabilistic Models};
	\arctext[PROB][SkyArc][5pt](4.50)(107)(75){|\scriptsize\color{black}| Unsupervised L.};
    
    % Problem Solving
    \arctext[SOLV][RedArc][8pt](2.75)(70)(23){|\footnotesize\bf\color{white}| Problem Solving};
    \arctext[SRCH][SkyArc][5pt](3.50)(70)(23){|\scriptsize\color{black}| Search };
    \arctext[HEUR][SkyArc][5pt](4.00)(70)(50){|\scriptsize| Heuristics};
	\arctext[ADVS][SkyArc][5pt](4.00)(47)(23){|\scriptsize| Adversarial S.};    
	\arctext[CONST][SkyArc][5pt](4.50)(70)(23){|\scriptsize\color{black}| Constraint Analysis };
	   
	% Natural Language Processing
	\arctext[NLP][RedArc][8pt](2.75)(20)(-17){|\footnotesize\bf\color{white}| NLP};
	\arctext[TRAN][SkyArc][5pt](3.50)(20)(-20){|\scriptsize\color{black}| Machine translation};
	\arctext[SPER][SkyArc][5pt](4.00)(20)(-20){|\scriptsize| Speech Recognition};
	\arctext[INFX][SkyArc][5pt](4.50)(20)(-20){|\scriptsize\color{black}| Information Extraction};    

    % Decision Making
    \arctext[DEC][RedArc][8pt](2.75)(293)(340){|\footnotesize\bf\color{white}| Decision Making};
    \arctext[LOG][SkyArc][5pt](3.50)(293)(335){|\scriptsize\color{black}| Logic};
    \arctext[KNOW][SkyArc][5pt](4.00)(293)(335){|\scriptsize| Knowledge Engineering};
    \arctext[PLAN][SkyArc][5pt](4.50)(293)(335){|\scriptsize| Real World Planning};
    
    % Reasoning
    \arctext[REAS][RedArc][8pt](2.75)(247)(291){|\footnotesize\bf\color{white} | Reasoning};
    \arctext[PROB][SkyArc][5pt](3.50)(247)(291){|\scriptsize\color{black}| Probabilistic R.};
    \arctext[REAT][SkyArc][5pt](4.00)(247)(271){|\scriptsize| Bayesian Nets};
    \arctext[REAT][SkyArc][5pt](4.00)(272)(291){|\scriptsize| R.over time};
    \arctext[UNQU][SkyArc][5pt](4.50)(247)(291){|\scriptsize\color{black}| Uncertainty Quantification};
    
    % Robotics
    \arctext[ROB][RedArc][8pt](2.75)(210)(245){|\footnotesize\bf\color{white}|  Robotics};
    \arctext[RPER][SkyArc][5pt](3.50)(210)(245){|\scriptsize\color{black}| R. Perception};
    \arctext[RACT][SkyArc][5pt](4.00)(210)(245){|\scriptsize| R. Actuation};
    \arctext[MAPL][SkyArc][5pt](4.50)(210)(245){|\scriptsize\color{black}| Mapping, Localization};
    
    % Object Recognition
    \arctext[RECO][RedArc][8pt](2.75)(145)(206){|\footnotesize\bf\color{white}| Object Recognition};
    \arctext[VIS][SkyArc][5pt](3.50)(145)(206){|\scriptsize\color{black}| Vision};
    \arctext[IMGP][SkyArc][5pt](4.00)(145)(175){|\scriptsize\color{black}| Image Processing };
    \arctext[IMGP][SkyArc][5pt](4.00)(176)(206){|\scriptsize\color{black}| 3D Reconstruction };
    \arctext[MOTC][SkyArc][5pt](4.50)(145)(206){|\scriptsize\color{black}| Motion, shading, contour analysis};   
  

%    %ADITIONAL EXTERNAL ARC
%   \arctext[NEW][
%       color=white,
%       shade,      
%       upper left=gray,
%       upper right=black!50,
%       lower left=gray,
%       lower right=gray!50,
%       rounded corners = 8pt
%       ][8pt](5.2)(180)(0){|\footnotesize\bf\color{white}| "Artificial Intelligence: A Modern Approach" by Peter Norvig and Stuart Russell};

    % Drawing the Arrows from contributing branch to AI
    % Format: \arcarrow(above/below ID)(abobe/below ID)[shift]
    \arcarrow(below ML)(AROUND)[30];
    \arcarrow(below SOLV)(AROUND)[24];
    \arcarrow(below NLP)(AROUND)[15];
    \arcarrow(below DEC)(AROUND)[-25];
    \arcarrow(below REAS)(AROUND)[-17];
    \arcarrow(below ROB)(AROUND)[-19];
    \arcarrow(below RECO)(AROUND)[-33];

    % Same level Arrows. Not needed now
    % \draw[myarrow] (left SSNX) -- (right DUAM);
    % \draw[myarrow] (left ML) -- (left SRel);
    % \draw[myarrow] (left SCap) -- (right ML);

	% Legend
    \draw[myarrow] (-5,-5) coordinate (legend) -- ++(.8,0) node[anchor=west] {(contribution)};
    \draw [RedArc] (legend)++(0,-0.4) rectangle ++(.8,-.3)++(0,.2) node [anchor=west, text width=3em] {capabilities,\\disciplines};
    \draw[SkyArc] (legend)++(0,-1) rectangle ++(.8,-.3)++(0,.2) node[anchor=west, color=black] {subfield};
        
    % source, book and authors
    \node [text width=6.45cm] at (1,-5.6) {Source: \textit {"Artificial Intelligence: A Modern Approach"} \\by Peter Norvig and Stuart Russell};        
    % copyright
	\node[text width=3cm] at (3,-6.25) {\begin{tiny}Copyright \textcopyright Alfonso R. Reyes, 2020\end{tiny}};

\end{tikzpicture}  
\end{document}

% Branches of Artificial Intelligence
% Drawn by Alfonso R. Reyes
% November 27, 2020
% Personal interpretation of "What is AI? / Branches of AI" article by Prof. John McCarthy.
% Original diagram: https://github.com/FriendlyUser/LatexDiagrams
\documentclass[border=5pt]{standalone}
\usepackage{xcolor}
\usepackage{ulem}


\definecolor{ocre}{HTML}{800000}
\definecolor{sky}{HTML}{C6D9F1}
\definecolor{skybox}{HTML}{5F86B3}

\usepackage{tikz}
\usepackage{pgfmath}
\usetikzlibrary{decorations.text, arrows.meta,calc,shadows.blur,shadings}

\renewcommand*\familydefault{\sfdefault} % Set font to serif family

% arctext from Andrew code with modifications:
%Variables: 1: ID, 2:Style 3:box height 4: Radious 5:start-angl 6:end-angl 7:text {format along path} 
\def\arctext[#1][#2][#3](#4)(#5)(#6)#7{
	\draw[#2] (#5:#4cm+#3) coordinate (above #1) arc (#5:#6:#4cm+#3)
	             -- (#6:#4) coordinate (right #1) -- (#6:#4cm-#3) coordinate (below right #1) arc (#6:#5:#4cm-#3) coordinate (below #1)
	             -- (#5:#4) coordinate (left #1) -- cycle;
	            \def\a#1{#4cm+#3}
	            \def\b#1{#4cm-#3}
	\path[
	    decoration={
	        raise = -0.5ex, % Controls relavite text height position.
	        text  along path,
	        text = {#7},
	        text align = center,        
	    },
	    decorate
	    ]
	    (#5:#4) arc (#5:#6:#4);
}

% arcarrow, this is mine, for beerware purpose...
% Function: Draw an arrow from arctex coordinate specific nodes to another 
% Arrow start at the start of arctext box and could be shifted to change the position
% to avoid go over another box.
% Var: 1:Start coordinate 2:End coordinate 3:angle to shift from acrtext box  
\def\arcarrow(#1)(#2)[#3]{
    \draw[very thick,->,>=latex,black!60] 
        let \p1 = (#1), \p2 = (#2), % To access cartesian coordinates x, and y.
            \n1 = {veclen(\x1,\y1)}, % Distance from the origin
            \n2 = {veclen(\x2,\y2)}, % Distance from the origin
            \n3 = {atan2(\y1,\x1)} % Angle where acrtext starts.
        in (\n3-#3: \n1) -- (\n3-#3: \n2); % Draw the arrow.
}


\begin{document}
\begin{tikzpicture}[
	    % Environment Cfg
	    font=\sf    \scriptsize,
	    % Styles
	    myarrow/.style={
	        thick,
	        -latex,
            black!60,
	    },
	    Center/.style ={
	        circle,
	        fill=ocre,
	        text=white,
	        align=center,
	        font =\footnotesize\bf,
	        inner sep=1pt,          
	    },
	    RedArc/.style ={
	        color=black,
	        thick,
	        fill=ocre,
	        blur shadow, 
	    },
	    SkyArc/.style ={
	        color=skybox,
	        thick,
	        fill=sky,
	        blur shadow, 
	    },
    ]

    % Drawing the center for AI
    \node[Center](AI) at (0,0) { Artificial \\ Intelligence \\(AI)\\ Agent};
    \coordinate (AROUND) at (0:1.2); 

    % Drawing the Text Arcs
    % Format: \Arctext[ID][box-style][box-height](radious)(start-angl)(end-angl){|text-styles| Text}
   
	% Logic
    \arctext[LOGI][RedArc][8pt](2.5)(120)(70){|\footnotesize\bf\color{white}| Logic};
	\arcarrow(below LOGI)(AROUND)[25];
    
    % Search
    \arctext[SRCH][RedArc][8pt](2.5)(60)(20){|\footnotesize\bf\color{white}| Search};
	\arcarrow(below SRCH)(AROUND)[20];
	   
	% Pattern Recognition
	\arctext[RECO][RedArc][8pt](2.5)(-60)(10){|\footnotesize\bf\color{white}| Pattern Recognition};
	\arcarrow(below RECO)(AROUND)[-35];

    % Representation
    \arctext[REPR][RedArc][8pt](2.5)(240)(290){|\footnotesize\bf\color{white}| Representation};
	\arcarrow(below REPR)(AROUND)[-25];
    
    % Inference
    \arctext[INFE][RedArc][8pt](2.5)(190)(230){|\footnotesize\bf\color{white} | Inference};    
    \arcarrow(below INFE)(AROUND)[-20];
    
    % Reasoning
    \arctext[REAS][RedArc][8pt](2.5)(180)(130){|\footnotesize\bf\color{white} | Reasoning};
	\arcarrow(below REAS)(AROUND)[25];
        
	% Epistemology
    \arctext[EPIS][RedArc][8pt](3.30)(220)(260){|\footnotesize\bf\color{white}|  Epistemology};

	% Planning
    \arctext[PLAN][RedArc][8pt](3.30)(210)(160){|\footnotesize\bf\color{white}| Planning};  
    
    % Learning
    \arctext[LEAR][RedArc][8pt](3.30)(150)(110){|\footnotesize\bf\color{white}| Learning};  

	% Ontology
    \arctext[ONTO][RedArc][8pt](3.30)(90)(50){|\footnotesize\bf\color{white}| Ontology};  
    
    % Heuristics
    \arctext[HEUR][RedArc][8pt](3.30)(40)(-10){|\footnotesize\bf\color{white}| Heuristics};  

	% Genetic Programming
	\arctext[GENE][RedArc][8pt](3.30)(270)(330){|\footnotesize\bf\color{white}| Genetic Programming};  
	

%    %ADITIONAL EXTERNAL ARC
%   \arctext[NEW][
%       color=white,
%       shade,      
%       upper left=gray!7,
%       upper right=gray!7,
%       lower left=gray!7,
%       lower right=gray!7,
%       rounded corners = 8pt
%       ][8pt](5.2)(180)(0){|\footnotesize\bf\color{black}| Interpration of "What is AI? / Branches of AI" article by Prof. John McCarthy.};

    % Drawing the Arrows from contributing branch to AI
    % Format: \arcarrow(above/below ID)(abobe/below ID)[shift]
    \arcarrow(below LEAR)(AROUND)[25];
    \arcarrow(below ONTO)(AROUND)[25];
    \arcarrow(below HEUR)(AROUND)[25];
    \arcarrow(below GENE)(AROUND)[-25];
    \arcarrow(below EPIS)(AROUND)[-15];
    \arcarrow(below PLAN)(AROUND)[25];
       

	% Legend and labels
    \draw[myarrow] (-5,-5) coordinate (legend) -- ++(.8,0) node[anchor=west] {(contribution)};
    \draw[RedArc] (legend)++(0,-0.4) rectangle ++(.8,-.3)++(0,.2) node[anchor=west, text width=3em] {capabilities,\\disciplines};
    \draw[SkyArc] (legend)++(0,-1) rectangle ++(.8,-.3)++(0,.2) node[anchor=west, color=black] {subfield};
    % source, book and authors
    \node [text width=5.5cm] at (1,-5.6) {Source: \textit {"What is AI? / Branches of AI"} article by Prof. John McCarthy. Stanford University.};
    % copyright
	\node[text width=3cm] at (3.25,-6.25) {\begin{tiny}Copyright \textcopyright Alfonso R. Reyes, 2020\end{tiny}};

\end{tikzpicture}  
\end{document}

% Computational Intelligence Agent Contributors
% Drawn by Alfonso R. Reyes
% November 2020
% Personal interpretation of "Computational Intelligence: A Logical Approach" by David Poole, Alan Mackworth and Randy Goebel.
% Original diagram: https://github.com/FriendlyUser/LatexDiagrams
\documentclass[border=5pt]{standalone}
\usepackage{xcolor}

	\definecolor{ocre}{HTML}{800000}
	\definecolor{sky}{HTML}{C6D9F1}
	\definecolor{skybox}{HTML}{5F86B3}

\usepackage{tikz}
\usepackage{pgfmath}
\usetikzlibrary{decorations.text, arrows.meta,calc,shadows.blur,shadings}

\renewcommand*\familydefault{\sfdefault} % Set font to serif family

% arctext from Andrew code with modifications:
%Variables: 1: ID, 2:Style 3:box height 4: Radious 5:start-angl 6:end-angl 7:text {format along path} 
\def\arctext[#1][#2][#3](#4)(#5)(#6)#7{

\draw[#2] (#5:#4cm+#3) coordinate (above #1) arc (#5:#6:#4cm+#3)
             -- (#6:#4) coordinate (right #1) -- (#6:#4cm-#3) coordinate (below right #1) arc (#6:#5:#4cm-#3) coordinate (below #1)
             -- (#5:#4) coordinate (left #1) -- cycle;
            \def\a#1{#4cm+#3}
            \def\b#1{#4cm-#3}
\path[
    decoration={
        raise = -0.5ex, % Controls relavite text height position.
        text  along path,
        text = {#7},
        text align = center,        
    },
    decorate
    ]
    (#5:#4) arc (#5:#6:#4);
}

% arcarrow, this is mine, for beerware purpose...
% Function: Draw an arrow from arctex coordinate specific nodes to another 
% Arrow start at the start of arctext box and could be shifted to change the position
% to avoid go over another box.
% Var: 1:Start coordinate 2:End coordinate 3:angle to shift from acrtext box  
\def\arcarrow(#1)(#2)[#3]{
    \draw[very thick,->,>=latex,black!60] 
        let \p1 = (#1), \p2 = (#2), % To access cartesian coordinates x, and y.
            \n1 = {veclen(\x1,\y1)}, % Distance from the origin
            \n2 = {veclen(\x2,\y2)}, % Distance from the origin
            \n3 = {atan2(\y1,\x1)} % Angle where acrtext starts.
        in (\n3-#3: \n1) -- (\n3-#3: \n2); % Draw the arrow.
}


\begin{document}
\begin{tikzpicture}[
	    % Environment Cfg
	    font=\sf    \scriptsize,
	    % Styles
	    myarrow/.style={
	        very thick,
	        -latex,
            black!60,
	    },
	    Center/.style ={
	        circle,
	        fill=ocre,
	        text=white,
	        align=center,
	        font =\footnotesize\bf,
	        inner sep=1pt,          
	    },
	    RedArc/.style ={
	        color=black,
	        thick,
	        fill=ocre,
	        blur shadow, 
	    },
	    SkyArc/.style ={
	        color=skybox,
	        thick,
	        fill=sky,
	        blur shadow, 
	    },
    ]

    % Drawing the center for AI
    \node[Center](AI) at (0,0) { Computational \\ Intelligence \\(AI)\\ Agent};
    \coordinate (AROUND) at (0:1.2); 

    % Drawing the Text Arcs
    % Format: \Arctext[ID][box-style][box-height](radious)(start-angl)(end-angl){|text-styles| Text}
    
	% Machine Learning
    \arctext[ML][RedArc][8pt](2.75)(135)(85){|\footnotesize\bf\color{white}| Machine Learning};
    \arctext[REIN][SkyArc][5pt](3.50)(135)(85){|\scriptsize\color{black}| Decision Trees};
    \arctext[KNOW][SkyArc][5pt](4.00)(135)(85){|\scriptsize| Neural Networks};
%    \arctext[SUPL][SkyArc][5pt](4.00)(140)(115){|\scriptsize| Supervised L.};
    \arctext[PROB][SkyArc][5pt](4.50)(135)(85){|\scriptsize\color{black}| Explanation Based Learning};
    
    % Problem Solving
    \arctext[SOLV][RedArc][8pt](2.75)(80)(40){|\footnotesize\bf\color{white}| Searching};
    \arctext[SRCH][SkyArc][5pt](3.50)(80)(40){|\scriptsize\color{black}| Graph Searching };
    \arctext[HEUR][SkyArc][5pt](4.00)(80)(40){|\scriptsize| Heuristic Search};
	\arctext[CONST][SkyArc][5pt](4.50)(80)(40){|\scriptsize\color{black}| Constraint Satisfaction};
	
	% Natural Language Processing
    \arctext[NLP][RedArc][8pt](2.75)(35)(-20){|\footnotesize\bf\color{white}| Definite Knowledge};
    \arctext[TRAN][SkyArc][5pt](3.50)(35)(5){|\scriptsize\color{black}| Recursion};
    \arctext[TRAN][SkyArc][5pt](3.50)(0)(-20){|\scriptsize\color{black}| NLP};
    \arctext[SPER][SkyArc][5pt](4.00)(35)(-20){|\scriptsize| Grammar Augmentation};
    \arctext[INFX][SkyArc][5pt](4.50)(35)(-20){|\scriptsize\color{black}| First Order Predicate Calculus};

    % Decision Making
    \arctext[DEC][RedArc][8pt](2.75)(290)(335){|\footnotesize\bf\color{white}| Planning};
    \arctext[LOG][SkyArc][5pt](3.50)(290)(335){|\scriptsize\color{black}| Time Representation};
    \arctext[KNOW][SkyArc][5pt](4.00)(290)(335){|\scriptsize| World Representations};
    \arctext[PLAN][SkyArc][5pt](4.50)(290)(335){|\scriptsize| Forward Planning};
    
    % Reasoning
    \arctext[REAS][RedArc][8pt](2.75)(250)(285){|\footnotesize\bf\color{white}|  Reasoning};
    \arctext[PROB][SkyArc][5pt](3.50)(250)(285){|\scriptsize\color{black}| Semantics};
    \arctext[REAT][SkyArc][5pt](4.00)(249)(287){|\scriptsize| Symbolic Representation};
    \arctext[UNQU][SkyArc][5pt](4.50)(248)(287){|\scriptsize\color{black}| Clauses, Questions, Answers};
    
    % Robotics
    \arctext[ROB][RedArc][8pt](2.75)(200)(245){|\footnotesize\bf\color{white}|  Robotics};
    \arctext[RPER][SkyArc][5pt](3.50)(200)(245){|\scriptsize\color{black}| Agent Functions};
    \arctext[RACT][SkyArc][5pt](4.00)(200)(245){|\scriptsize| Robotic Systems};
    \arctext[MAPL][SkyArc][5pt](4.50)(200)(224){|\scriptsize\color{black}| Agent Models};
    \arctext[MAPL][SkyArc][5pt](4.50)(226)(245){|\scriptsize\color{black}| Architecture};
    
    % Object Recognition
    \arctext[RECO][RedArc][8pt](2.75)(140)(195){|\footnotesize\bf\color{white}| Knowledge};
    \arctext[VIS][SkyArc][5pt](3.50)(140)(195){|\scriptsize\color{black}| Representation Language};
    \arctext[IMGP][SkyArc][5pt](4.00)(140)(195){|\scriptsize\color{black}| Map Problem to Representation };
    \arctext[MOTC][SkyArc][5pt](4.50)(140)(195){|\scriptsize\color{black}| Knowledge Based Systems};   
  

%    %ADITIONAL EXTERNAL ARC
%    \arctext[NEW][
%        color=white,
%        shade,      
%        upper left=gray,
%        upper right=black!50,
%        lower left=gray,
%        lower right=gray!50,
%        rounded corners = 8pt
%        ][8pt](5.2)(180)(0){|\footnotesize\bf\color{white}| "Computational Intelligence: A Logical Approach" by David Poole, Alan Mackworth and Randy Goebel};

    % Drawing the Arrows from contributing branch to AI
    % Format: \arcarrow(above/below ID)(abobe/below ID)[shift]
    \arcarrow(below ML)(AROUND)[30];
    \arcarrow(below SOLV)(AROUND)[24];
    \arcarrow(below NLP)(AROUND)[15];
    \arcarrow(below DEC)(AROUND)[-25];
    \arcarrow(below REAS)(AROUND)[-17];
    \arcarrow(below ROB)(AROUND)[-19];
    \arcarrow(below RECO)(AROUND)[-33];

    % Same level Arrows. Not needed now
    % \draw[myarrow] (left SSNX) -- (right DUAM);
    % \draw[myarrow] (left ML) -- (left SRel);
    % \draw[myarrow] (left SCap) -- (right ML);

	% Color Legend and labels
    \draw [myarrow] (-5,-5) coordinate (legend) -- ++(.8,0) node[anchor=west] {(contribution)};
    \draw [RedArc] (legend)++(0,-0.4) rectangle ++(.8,-.3)++(0,.2) node [anchor=west, text width=3em] {capabilities,\\disciplines};
    \draw [SkyArc] (legend)++(0,-1) rectangle ++(.8,-.3)++(0,.2) node[anchor=west, color=black] {subfield};
    % source, book and authors
    \node [text width=6.45cm] at (1,-5.6) {Source: \textit {"Computational Intelligence: A Logical Approach"} \\by David Poole, Alan Mackworth and Randy Goebel};
    % copyright
	\node [text width=3cm] at (3.25,-6.25) {\begin{tiny}Copyright \textcopyright Alfonso R. Reyes, 2020\end{tiny}};

\end{tikzpicture}  
\end{document}

% https://tex.stackexchange.com/a/347917/173708

\documentclass[tikz]{standalone}

\usepackage{verbatim}

\begin{comment}
This example is a demonstration of an animation by creating a GIF file out of
a PDF file with several pages. Once the PDF file has been created with the 
"pgfmathsetmacro" macor, convert the PDF file to a GIF. 
Create the gif with:

  convert -delay 0 -density 120 animation-dynamic_labels.pdf animation-dynamic_labels.gif

\end{comment}  

\begin{document}
% this will produce the animation by creating 80 small PDF files
% later we will need to build the GIF file
\foreach {\tangle} in {80,79,...,10}{
  \pgfmathsetmacro{\sangle}{-\tangle}

\begin{tikzpicture}[auto]
    % constants
    \def\rinn{2}
    \def\rout{3.8}

    % just to fix the global bounding box
    \path circle[radius=\rout cm+5mm+2em];

    \draw (0,0) circle [radius=\rinn];
    \draw (0,0) circle [radius=\rout];

    \coordinate (T1) at (\tangle:\rinn);
    \coordinate (T2) at (\tangle:\rout);
    \coordinate (S1) at (\sangle:\rinn);
    \coordinate (S2) at (\sangle:\rout);

    \draw (0,0) -- (T1) -- (T2);
    \draw (0,0) -- (S1) -- (S2);

    \path (T1) ++(\tangle+45:5mm) node{T1};
    \path (T2) ++(\tangle+45:5mm) node{T2};
    \path (S1) ++(\sangle-45:5mm) node{S1};
    \path (S2) ++(\sangle-45:5mm) node{S2};

\end{tikzpicture}
}
\end{document}

% https://tex.stackexchange.com/a/52766/173708
\documentclass{standalone}

\usepackage{tikz}
\usetikzlibrary{shapes,positioning,arrows,calc}

\begin{document}

\begin{tikzpicture}[stack/.style={
  rectangle split, rectangle split parts=5, draw, anchor=center},
  myarrow/.style={single arrow, draw=none}]

  \node [stack] (ini)  {$a=0$\nodepart{two}$b=10$%
    \nodepart{three}$c=100$\nodepart{four}$d=-10$\nodepart{five}$\cdots$};

  \node [draw,rectangle,align=left,right=of ini,label=above:{Computer Program}] (mid)
    {instruction 0;\\ instruction 1;\\$\ldots$\\instruction $n$;};

  \node [stack,right=of mid] (fin) {$a=10$\nodepart{two}$b=100$%
    \nodepart{three}$c=-10$\nodepart{four}$d=110$\nodepart{five}$\cdots$};

  \node [above=of ini,anchor=north,align=left] {Initial values of\\variables};
  \node [above=of fin,anchor=north,align=left] {Final values of\\variables};

  \node [myarrow,draw,anchor=west] at ($(ini.east)+(2.5pt,0)$) {\phantom{te}} ;
  \node [myarrow,draw,anchor=west] at ($(mid.east)+(2.5pt,0)$) {\phantom{te}} ;

\end{tikzpicture}

\end{document}

% https://tex.stackexchange.com/questions/33150/creating-node-shapes?rq=1
\documentclass[border=10pt]{standalone}

\usepackage{tikz}

\makeatletter
\tikzset{arc style/.initial={}}
\pgfdeclareshape{circle with arcs}{
    \inheritsavedanchors[from=circle]
    \inheritanchorborder[from=circle]

    \inheritanchor[from=circle]{center}
    \inheritanchor[from=circle]{south}
    \inheritanchor[from=circle]{west}
    \inheritanchor[from=circle]{north}
    \inheritanchor[from=circle]{east}
    % etc.

    \inheritbackgroundpath[from=circle]

    \beforebackgroundpath{
        % get and set options
        \pgfkeys{/tikz/arc style/.get=\tmp}
        \expandafter\tikzset\expandafter{\tmp}
        \tikz@options

        % get radius length and center coordinates
        \radius \pgf@xa=\pgf@x
        \centerpoint \pgf@xb=\pgf@x \pgf@yb=\pgf@y

        % draw arc starting from north
        \advance\pgf@yb by\pgf@xa
        \pgfpathmoveto{\pgfpoint{\pgf@xb}{\pgf@yb}}
        \pgfpatharc{180}{270}{\pgf@xa}

        % draw arc starting from south
        \advance\pgf@yb by -2\pgf@xa
        \pgfpathmoveto{\pgfpoint{\pgf@xb}{\pgf@yb}}
        \pgfpatharc{0}{90}{\pgf@xa}

        \pgfusepath{draw}
    }
}
\makeatother

\begin{document}
\begin{tikzpicture}
    \draw[help lines, gray, dotted] (-2,-2) grid (2,2);
    \node[
        circle with arcs,
        draw=gray,
        fill=blue!20,
        minimum width=2cm,
        arc style={black,thick}
        ] (c) {1};
    \draw[thick,gray,dotted]
        (c.north) -- +(0,1)
        (c.east)  -- +(1,0)
        (c.south) -- +(0,-1)
        (c.west)  -- +(-1,0);
\end{tikzpicture}
\end{document}

% Class diagram
% Author: Remus Mihail Prunescu

% arr: change colors. 
\documentclass{minimal}
\usepackage[a4paper,margin=1cm,landscape]{geometry}
\usepackage{tikz}

%%%<
\usepackage{verbatim}
\usepackage[active,tightpage]{preview}
\PreviewEnvironment{tikzpicture}
\setlength\PreviewBorder{5pt}%
%%%>

\begin{comment}
:Title:  Class diagram

\end{comment}

\usetikzlibrary{positioning,shapes,shadows,arrows}

\begin{document}
\tikzstyle{abstract}=[rectangle, draw=black, rounded corners, fill=black!40!blue!60, drop shadow,
        text centered, anchor=north, text=white, text width=3cm]
\tikzstyle{comment}=[rectangle, draw=black, rounded corners, fill=black!60!green, drop shadow,
        text centered, anchor=north, text=white, text width=3cm]
\tikzstyle{myarrow}=[->, >=open triangle 90, thick]
\tikzstyle{line}=[-, thick]
        
\begin{center}
\begin{tikzpicture}[node distance=2cm]
    \node (Item) [abstract, rectangle split, rectangle split parts=2]
        {
            \textbf{ITEM}
            \nodepart{second}name
        };
    \node (AuxNode01) [text width=4cm, below=of Item] {};
    \node (Component) [abstract, rectangle split, rectangle split parts=2, left=of AuxNode01]
        {
            \textbf{COMPONENT}
            \nodepart{second}nil
        };
    \node (System) [abstract, rectangle split, rectangle split parts=2, right=of AuxNode01]
        {
            \textbf{SYSTEM}
            \nodepart{second}parts
        };
    \node (AuxNode02) [text width=0.5cm, below=of Component] {};
    \node (Sensor) [abstract, rectangle split, rectangle split parts=2, left=of AuxNode02]
        {
            \textbf{SENSOR}
            \nodepart{second}nil
        };
    \node (Part) [abstract, rectangle split, rectangle split parts=2, right=of AuxNode02]
        {
            \textbf{PART}
            \nodepart{second}nil
        };
        
    \node (AuxNode03) [below=of Sensor] {};
    \node (Pressure) [abstract, rectangle split, rectangle split parts=2, left=of AuxNode03, xshift=2cm]
        {
            \textbf{Pressure}
            \nodepart{second}nil
        };
    \node (Temperature) [abstract, rectangle split, rectangle split parts=2, right=of AuxNode03, xshift=-2cm]
        {
            \textbf{Temperature}
            \nodepart{second}nil
        };
    \node (PressureInstants) [comment, rectangle split, rectangle split parts=2, below=0.2cm of Pressure, text justified]
        {
            \textbf{Instants}
            \nodepart{second}fw-p-suction\newline fw-p-delivery\newline fw-p-loop\newline sw-p-suction\newline sw-p-delivery
                \newline sw-p-loop
        };
    \node (ClOp) [abstract, rectangle split, rectangle split parts=2, below=0.4cm of PressureInstants]
        {
            \textbf{Closed/Open}
            \nodepart{second}nil
        };
    \node (ClOpInstants) [comment, rectangle split, rectangle split parts=2, below=0.2cm of ClOp, text justified]
        {
            \textbf{Instants}
            \nodepart{second}fw-clop-warm-up\newline sw-clop-control
        };
    \node (TemperatureInstants) [comment, rectangle split, rectangle split parts=2, below=0.2cm of Temperature, text justified]
        {
            \textbf{Instants}
            \nodepart{second}fw-t-engine\newline fw-t-heat-exch.\newline sw-t-heat-exch.
        };
    \node (Level) [abstract, rectangle split, rectangle split parts=2, below=0.4cm of TemperatureInstants]
        {
            \textbf{Level}
            \nodepart{second}nil
        };
    \node (LevelInstants) [comment, rectangle split, rectangle split parts=2, below=0.2cm of Level, text justified]
        {
            \textbf{Instants}
            \nodepart{second}fw-l-tank
        };
    \node (Ammeter) [abstract, rectangle split, rectangle split parts=2, below=0.4cm of LevelInstants]
        {
            \textbf{Ammeter}
            \nodepart{second}nil
        };
    \node (AmmeterInstants) [comment, rectangle split, rectangle split parts=2, below=0.2cm of Ammeter, text justified]
        {
            \textbf{Instants}
            \nodepart{second}fw-pump-ammeter\newline sw-pump-ammeter
        };
        
    \node (AuxNode04) [below=of Part] {};
    \node (Pump) [abstract, rectangle split, rectangle split parts=2, left=of AuxNode04, xshift=2cm]
        {
            \textbf{Pump}
            \nodepart{second}nil
        };
    \node (Valve) [abstract, rectangle split, rectangle split parts=2, right=of AuxNode04, xshift=-2cm]
        {
            \textbf{Valve}
            \nodepart{second}nil
        };
    \node (PumpInstants) [comment, rectangle split, rectangle split parts=2, below=0.2cm of Pump, text justified]
        {
            \textbf{Instants}
            \nodepart{second}fw-pump\newline sw-pump
        };
    \node (Tank) [abstract, rectangle split, rectangle split parts=2, below=0.4cm of PumpInstants]
        {
            \textbf{Tank}
            \nodepart{second}nil
        };
    \node (ValveInstants) [comment, rectangle split, rectangle split parts=2, below=0.2cm of Valve, text justified]
        {
            \textbf{Instants}
            \nodepart{second}fw-suction-valve\newline fw-delivery-valve\newline sw-suction-valve\newline sw-delivery-valve
                \newline sw-discharge-valve\newline sw-control-valve
        };
    \node (Engine) [abstract, rectangle split, rectangle split parts=2, below=0.4cm of ValveInstants]
        {
            \textbf{Engine}
            \nodepart{second}nil
        };
    \node (TankInstants) [comment, rectangle split, rectangle split parts=2, below=0.2cm of Tank, text justified]
        {
            \textbf{Instants}
            \nodepart{second}fw-expansion-tank
        };
    \node (HeatExchanger) [abstract, rectangle split, rectangle split parts=2, below=0.4cm of TankInstants]
        {
            \textbf{Heat Exchanger}
            \nodepart{second}nil
        };
    \node (HeatExchangerInstants) [comment, rectangle split, rectangle split parts=2, below=0.2cm of HeatExchanger, text justified]
        {
            \textbf{Instants}
            \nodepart{second}fw-heat-exchanger
        };
    \node (EngineInstants) [comment, rectangle split, rectangle split parts=2, below=0.2cm of Engine, text justified]
        {
            \textbf{Instants}
            \nodepart{second}fw-engine
        };
    \node (Strainer) [abstract, rectangle split, rectangle split parts=2, below=0.4cm of HeatExchangerInstants]
        {
            \textbf{Strainer}
            \nodepart{second}nil
        };
    \node (StrainerInstants) [comment, rectangle split, rectangle split parts=2, below=0.2cm of Strainer, text justified]
        {
            \textbf{Instants}
            \nodepart{second}sw-strainer
        };
    \node (Coolant) [abstract, rectangle split, rectangle split parts=2, below=0.4cm of EngineInstants]
        {
            \textbf{Coolant}
            \nodepart{second}nil
        };
    \node (CoolantInstants) [comment, rectangle split, rectangle split parts=2, below=0.2cm of Coolant, text justified]
        {
            \textbf{Instants}
            \nodepart{second}fw-coolant\newline sw-coolant
        };  

    \node (AuxNode05) [below=of System] {};
    \node (CoolingSystem) [abstract, rectangle split, rectangle split parts=2, left=of AuxNode05, xshift=2cm]
        {
            \textbf{Cooling System}
            \nodepart{second}nil
        };
    \node (CoolingLoop) [abstract, rectangle split, rectangle split parts=2, right=of AuxNode05, xshift=-2cm]
        {
            \textbf{Cooling Loop}
            \nodepart{second}nil
        };
    \node (CoolingSystemInstants) [comment, rectangle split, rectangle split parts=2, below=0.2cm of CoolingSystem, text justified]
        {
            \textbf{Instants}
            \nodepart{second}cool
        };
    \node (CoolingLoopInstants) [comment, rectangle split, rectangle split parts=2, below=0.2cm of CoolingLoop, text justified]
        {
            \textbf{Instants}
            \nodepart{second}fw-loop\newline sw-loop
        };
    
    \draw[myarrow] (Component.north) -- ++(0,0.8) -| (Item.south);
    \draw[line] (Component.north) -- ++(0,0.8) -| (System.north);
    
    \draw[myarrow] (Sensor.north) -- ++(0,0.8) -| (Component.south);
    \draw[line] (Sensor.north) -- ++(0,0.8) -| (Part.north);
    
    \draw[line] (Pressure.west) -- ++(-0.2,0);
    \draw[line] (Temperature.east) -- ++(0.2,0);
    \draw[line] (Level.east) -- ++(0.2,0);
    \draw[myarrow] (ClOp.west) -- ++(-0.2,0) -- ([yshift=0.5cm, xshift=-0.2cm] Pressure.north west) -|
     ([xshift=-1cm]Sensor.south);
    \draw[myarrow] (Ammeter.east) -- ++(0.2,0) -- ([yshift=0.5cm, xshift=0.2cm] Temperature.north east) -|
     ([xshift=1cm]Sensor.south);
     
    \draw[line] (Tank.west) -- ++(-0.2,0);
    \draw[line] (HeatExchanger.west) -- ++(-0.2,0);
    \draw[line] (Pump.west) -- ++(-0.2,0);
    \draw[line] (Valve.east) -- ++(0.2,0);
    \draw[line] (Engine.east) -- ++(0.2,0);
    \draw[myarrow] (Strainer.west) -- ++(-0.2,0) -- ([yshift=0.5cm, xshift=-0.2cm] Pump.north west) -|
     ([xshift=-1cm]Part.south);
    \draw[myarrow] (Coolant.east) -- ++(0.2,0) -- ([yshift=0.5cm, xshift=0.2cm] Valve.north east) -|
     ([xshift=1cm]Part.south);
     
    \draw[myarrow] (CoolingSystem.north) -- ++(0,0.8) -| (System.south);
    \draw[line] (CoolingSystem.north) -- ++(0,0.8) -| (CoolingLoop.north);
        
        
\end{tikzpicture}
\end{center}
\end{document}

% https://www.overleaf.com/read/cvmtqywqgvvw#/43203532/
% https://betterexplained.com/articles/colorized-math-equations/

% \documentclass{article}
\documentclass[preview]{standalone}
\usepackage[utf8]{inputenc}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage{color}

\newcommand{\plain}{\color{black}}
\newcommand{\Frac}[2]{\genfrac{}{}{1pt}{}{#1}{#2}}	% thicker fraction line

\definecolor{c1}{RGB}{114,0,172}   % primary
\definecolor{c2}{RGB}{45,177,93}   % true
\definecolor{c3}{RGB}{251,0,29}    % false
\definecolor{c4}{RGB}{18,110,213}  % secondary
\definecolor{c5}{RGB}{255,160,109} % tertiary
\definecolor{c6}{RGB}{219,78,158}  % alt-primary 

\renewcommand{\familydefault}{\sfdefault}

\begin{document}
\begin{center}

\newcommand{\growth}{\color{c1}}
\newcommand{\unitQuantity}{\color{c2}}
\newcommand{\unitInterest}{\color{c3}}
\newcommand{\unitTime}{\color{c4}}
\newcommand{\perfectly}{\color{c5}}
\newcommand{\compounded}{\color{c6}}

$$\growth e
\plain =
\perfectly \lim_{n\to\infty}
\plain \left(
\unitQuantity 1 + \unitInterest \frac{1}{\compounded n}
\plain \right)
\unitTime^{1 \cdot \compounded n}
$$

\growth       The base for continuous growth
\plain        is
\\
\unitQuantity the unit quantity 
\unitInterest earning unit interest
\unitTime     for unit time, 
\\
\compounded   compounded
\perfectly    as fast as possible

\end{center}
\end{document}

% include TIKZ_PREAMBLE.pgs
\documentclass[parskip]{scrartcl}

\usepackage{tikz}
\usepackage{pgfplots}

\begin{document}

\tikzset{
  vertex/.style={
    circle, minimum size=20pt, inner sep=0pt, fill=gray!10},
  axial/.style={
    rectangle, minimum size=20pt, inner sep=0pt, fill=gray!30},
  edge/.style={draw,thick,-,black},
  rotu/.style={midway},
  sinal/.style={draw, circle, inner sep=0pt, thin}
}

\def\dist{0.4}
\begin{tikzpicture}[
  scale=2, ->, thick, z={(0.45,0.35)}, node distance=0.65cm]
  \node[vertex] (v0) at (0,0,0) {$(1)$};
  \node[vertex] (v1) at (0,1,0) {$b$};
  \node[vertex] (v2) at (1,0,0) {$a$};
  \node[vertex] (v3) at (1,1,0) {$ab$};
  \node[vertex] (v4) at (0,0,1) {$c$};
  \node[vertex] (v5) at (0,1,1) {$bc$};
  \node[vertex] (v6) at (1,0,1) {$ac$};
  \node[vertex] (v7) at (1,1,1) {$abc$};
  \draw[edge] (v0) -- (v1) node[rotu, left=\dist] {$B$} -- 
    (v3) -- (v2) -- (v0) node[rotu, below=\dist] {$A$};
  \draw[edge] (v0) -- (v4) -- (v5) -- (v1);
  \draw[edge] (v2) -- (v6)
    node[rotu, below right=\dist] {$C$} -- (v7) -- (v3);
  \draw[edge] (v4) -- (v6); \draw[edge] (v5) -- (v7);
  \node[sinal, below of=v0] {$-$};
  \node[sinal, left of=v0] {$-$};
  \node[sinal, left of=v1] {$+$};
  \node[sinal, below of=v2] {$+$};
  \node[sinal, right of=v3] {$-$};
  \node[sinal, right of=v7] {$+$};
\end{tikzpicture}

\def\dist{0.4}
\def\ax{2}
\begin{tikzpicture}[
  scale=2, ->, thick, z={(0.55,0.3)}, node distance=0.65cm]
  \node[vertex, fill=yellow] (c0) at (0,0,0) {$0$};
  \node[vertex] (v0) at (-1,-1,-1) {$(1)$};
  \node[vertex] (v1) at (-1,1,-1) {$b$};
  \node[vertex] (v2) at (1,-1,-1) {$a$};
  \node[vertex] (v3) at (1,1,-1) {$ab$};
  \node[vertex] (v4) at (-1,-1,1) {$c$};
  \node[vertex] (v5) at (-1,1,1) {$bc$};
  \node[vertex] (v6) at (1,-1,1) {$ac$};
  \node[vertex] (v7) at (1,1,1) {$abc$};
  \node[axial] (a1) at (-\ax,0,0) {$W$};
  \node[axial] (a2) at (\ax,0,0) {$W$};
  \node[axial] (a3) at (0,-\ax,0) {$W$};
  \node[axial] (a4) at (0,\ax,0) {$W$};
  \node[axial] (a5) at (0,0,-\ax) {$W$};
  \node[axial] (a6) at (0,0,\ax) {$W$};
  \draw[edge] (v0) -- (v1) node[rotu, left=\dist] {$B$} -- 
    (v3) -- (v2) -- (v0) node[rotu, below=\dist] {$A$};
  \draw[edge] (v0) -- (v4) -- (v5) -- (v1);
  \draw[edge] (v2) -- (v6)
    node[rotu, below right=\dist] {$C$} -- (v7) -- (v3);
  \draw[edge] (v4) -- (v6); \draw[edge] (v5) -- (v7);
  \draw[edge] (a1) -- (c0) --(a2);
  \draw[edge] (a3) -- (c0) --(a4);
  \draw[edge] (a5) -- (c0) --(a6);
  \node[sinal, below of=v0] {$-$};
  \node[sinal, left of=v0] {$-$};
  \node[sinal, left of=v1] {$+$};
  \node[sinal, below of=v2] {$+$};
  \node[sinal, right of=v3] {$-$};
  \node[sinal, right of=v7] {$+$};
\end{tikzpicture}

\begin{tikzpicture}[
  scale=2, ->, thick, z={(0.45,0.35)}, node distance=0.65cm,
  vertex/.style={
    rectangle, minimum size=12pt, inner sep=1pt, fill=gray!10
  }]
  \node[text centered] (title) at (0.7,1.7,0)
    {Rendimento (\%) em um $2^3$};
  \node[vertex] (v0) at (0,0,0) {$54.8$};
  \node[vertex] (v1) at (0,1,0) {$48.0$};
  \node[vertex] (v2) at (1,0,0) {$86.5$};
  \node[vertex] (v3) at (1,1,0) {$63.0$};
  \node[vertex] (v4) at (0,0,1) {$63.0$};
  \node[vertex] (v5) at (0,1,1) {$58.5$};
  \node[vertex] (v6) at (1,0,1) {$93.5$};
  \node[vertex] (v7) at (1,1,1) {$72.0$};
  \draw[edge] (v0) -- (v1)
    node[rotu, rotate=90, yshift=1.2cm] {Catalizador} -- 
    (v3) -- (v2) -- (v0) node[rotu, below=0.9cm] {Temperatura};
  \draw[edge] (v0) -- (v4) -- (v5) -- (v1);
  \draw[edge] (v2) -- (v6)
    node[rotu, rotate=40, yshift=-1cm, xshift=0.5cm]
    {Concentra\c{c}\~ao} -- (v7) -- (v3);
  \draw[edge] (v4) -- (v6); \draw[edge] (v5) -- (v7);
  \node[sinal, below of=v0] {$-$};
  \node[sinal, left of=v0] {$-$};
  \node[sinal, left of=v1] {$+$};
  \node[sinal, below of=v2] {$+$};
  \node[sinal, right of=v3] {$-$};
  \node[sinal, right of=v7] {$+$};
\end{tikzpicture}


\end{document}

% https://tex.stackexchange.com/a/247338/173708
% https://tex.stackexchange.com/questions/247202/creating-tikz-libraries?noredirect=1&lq=1
% calls tikzlibraryunitscircle.code.tex
\documentclass[border=10pt]{standalone}
\usepackage{tikz}
\usetikzlibrary{calc}
\usetikzlibrary{unitcircle}   % using  tikzlibraryunitcircle.code.tex
\begin{document}

\begin{tikzpicture}

  \path
              (0,0) pic (LL) {quadrant III}
        -- ++ (1,0) pic (LR) {quadrant IV}
        -- ++ (0,1) pic (UR) {quadrant I}
        -- cycle
        -- ++ (0,1) pic (UL) {quadrant II}
      ;
  \draw[blue] (LR-ne) -- (LR-sw);

  \draw[red] (LL-ne) rectangle (LL-sw);

  \draw (LL-center) -- (UR-center)
                    -- (UL-center)
                    -- (LR-center);
\end{tikzpicture}

\end{document}

% https://tex.stackexchange.com/a/21396/173708

\documentclass{article}
\usepackage{tikz} 
\usetikzlibrary{shapes}  

% split figures into pages
\usepackage[active,tightpage]{preview}
\PreviewEnvironment{tikzpicture}
\setlength\PreviewBorder{1pt}%


\begin{document}
	
\thispagestyle{empty} 

 \begin{tikzpicture}[
    transformer/.style 2 args={draw, 
    	cylinder, 
    	gray!80, 
    	rotate=90, 
    	minimum height=#1, 
    	minimum width=#2}]

	\node [transformer={2.3cm}{1cm}] () at (0,0.6) {};
\end{tikzpicture}  

% using n args={}{}
 \begin{tikzpicture}[
	transformer2/.style n args={2}{draw, 
		cylinder, 
		gray!50, 
		rotate=45, 
		minimum height=#1, 
		minimum width=#2}]

	\node [transformer2={2.3cm}{1cm}] () at (0,0.6) {};
\end{tikzpicture} 

%\begin{tikzpicture}[
% 	\def\mh{2.3cm}
% 	\def\mw{1cm} 	
%	transformer3/.style args={mh, mw}{draw, 
%		cylinder, 
%		gray!50, 
%		rotate=45, 
%		minimum height=mh, 
%		minimum width=mw}]
%
%	\node [transformer3={2.3cm}{1cm}] () at (0,0.6) {};
%\end{tikzpicture} 

\end{document} 

% https://davidstutz.de/illustrating-convolutional-neural-networks-in-latex-with-tikz/

\documentclass[twoside,11pt,a4paper]{article}
 
\usepackage[utf8]{inputenc}
\usepackage{amsmath, amssymb, latexsym}
 
\usepackage[left=2cm,right=2cm,top=2cm,bottom=2cm]{geometry}
\usepackage{tikz}
\usetikzlibrary{decorations.pathreplacing}
\usetikzlibrary{fadings}
 
\begin{document}
 
\begin{figure}[t!]
   	\centering
   	\begin{tikzpicture}
   		\node at (0.5,-1){\begin{tabular}{c}input image\\layer $l = 0$\end{tabular}};
   		
   		\draw (0,0) -- (1,0) -- (1,1) -- (0,1) -- (0,0);
   		
   		\node at (3,3.5){\begin{tabular}{c}convolutional layer\\with non-linearities\\layer $l = 1$\end{tabular}};
   		
   		\draw[fill=black,opacity=0.2,draw=black] (2.75,1.25) -- (3.75,1.25) -- (3.75,2.25) -- (2.75,2.25) -- (2.75,1.25);
   		\draw[fill=black,opacity=0.2,draw=black] (2.5,1) -- (3.5,1) -- (3.5,2) -- (2.5,2) -- (2.5,1);
   		\draw[fill=black,opacity=0.2,draw=black] (2.25,0.75) -- (3.25,0.75) -- (3.25,1.75) -- (2.25,1.75) -- (2.25,0.75);
   		\draw[fill=black,opacity=0.2,draw=black] (2,0.5) -- (3,0.5) -- (3,1.5) -- (2,1.5) -- (2,0.5);
   		\draw[fill=black,opacity=0.2,draw=black] (1.75,0.25) -- (2.75,0.25) -- (2.75,1.25) -- (1.75,1.25) -- (1.75,0.25);
   		\draw[fill=black,opacity=0.2,draw=black] (1.5,0) -- (2.5,0) -- (2.5,1) -- (1.5,1) -- (1.5,0);
   		
   		\node at (4.5,-1){\begin{tabular}{c}subsampling layer\\layer $l = 3$\end{tabular}};
   		
   		\draw[fill=black,opacity=0.2,draw=black] (5,1.25) -- (5.75,1.25) -- (5.75,2) -- (5,2) -- (5,1.25);
   		\draw[fill=black,opacity=0.2,draw=black] (4.75,1) -- (5.5,1) -- (5.5,1.75) -- (4.75,1.75) -- (4.75,1);
   		\draw[fill=black,opacity=0.2,draw=black] (4.5,0.75) -- (5.25,0.75) -- (5.25,1.5) -- (4.5,1.5) -- (4.5,0.75);
   		\draw[fill=black,opacity=0.2,draw=black] (4.25,0.5) -- (5,0.5) -- (5,1.25) -- (4.25,1.25) -- (4.25,0.5);
   		\draw[fill=black,opacity=0.2,draw=black] (4,0.25) -- (4.75,0.25) -- (4.75,1) -- (4,1) -- (4,0.25);
   		\draw[fill=black,opacity=0.2,draw=black] (3.75,0) -- (4.5,0) -- (4.5,0.75) -- (3.75,0.75) -- (3.75,0);
   		
   		\node at (7,3.5){\begin{tabular}{c}convolutional layer\\with non-linearities\\layer $l = 4$\end{tabular}};
   		
   		\draw[fill=black,opacity=0.2,draw=black] (7.5,1.75) -- (8.25,1.75) -- (8.25,2.5) -- (7.5,2.5) -- (7.5,1.75);
   		\draw[fill=black,opacity=0.2,draw=black] (7.25,1.5) -- (8,1.5) -- (8,2.25) -- (7.25,2.25) -- (7.25,1.5);
   		\draw[fill=black,opacity=0.2,draw=black] (7,1.25) -- (7.75,1.25) -- (7.75,2) -- (7,2) -- (7,1.25);
   		\draw[fill=black,opacity=0.2,draw=black] (6.75,1) -- (7.5,1) -- (7.5,1.75) -- (6.75,1.75) -- (6.75,1);
   		\draw[fill=black,opacity=0.2,draw=black] (6.5,0.75) -- (7.25,0.75) -- (7.25,1.5) -- (6.5,1.5) -- (6.5,0.75);
   		\draw[fill=black,opacity=0.2,draw=black] (6.25,0.5) -- (7,0.5) -- (7,1.25) -- (6.25,1.25) -- (6.25,0.5);
   		\draw[fill=black,opacity=0.2,draw=black] (6,0.25) -- (6.75,0.25) -- (6.75,1) -- (6,1) -- (6,0.25);
   		\draw[fill=black,opacity=0.2,draw=black] (5.75,0) -- (6.5,0) -- (6.5,0.75) -- (5.75,0.75) -- (5.75,0);
   		
   		\node at (9.5,-1){\begin{tabular}{c}subsampling layer\\layer $l = 6$\end{tabular}};
   		
   		\draw[fill=black,opacity=0.2,draw=black] (10,1.75) -- (10.5,1.75) -- (10.5,2.25) -- (10,2.25) -- (10,1.75);
   		\draw[fill=black,opacity=0.2,draw=black] (9.75,1.5) -- (10.25,1.5) -- (10.25,2) -- (9.75,2) -- (9.75,1.5);
   		\draw[fill=black,opacity=0.2,draw=black] (9.5,1.25) -- (10,1.25) -- (10,1.75) -- (9.5,1.75) -- (9.5,1.25);
   		\draw[fill=black,opacity=0.2,draw=black] (9.25,1) -- (9.75,1) -- (9.75,1.5) -- (9.25,1.5) -- (9.25,1);
   		\draw[fill=black,opacity=0.2,draw=black] (9,0.75) -- (9.5,0.75) -- (9.5,1.25) -- (9,1.25) -- (9,0.75);
   		\draw[fill=black,opacity=0.2,draw=black] (8.75,0.5) -- (9.25,0.5) -- (9.25,1) -- (8.75,1) -- (8.75,0.5);
   		\draw[fill=black,opacity=0.2,draw=black] (8.5,0.25) -- (9,0.25) -- (9,0.75) -- (8.5,0.75) -- (8.5,0.25);
   		\draw[fill=black,opacity=0.2,draw=black] (8.25,0) -- (8.75,0) -- (8.75,0.5) -- (8.25,0.5) -- (8.25,0);
   		
   		\node at (12,3.5){\begin{tabular}{c}fully connected layer\\layer $l = 7$\end{tabular}};
   		
   		\draw[fill=black,draw=black,opacity=0.5] (10.5,0) -- (11,0) -- (12.5,1.75) -- (12,1.75) -- (10.5,0);
   		
   		\node at (13,-1){\begin{tabular}{c}fully connected layer\\output layer $l = 8$\end{tabular}};
   		
   		\draw[fill=black,draw=black,opacity=0.5] (12.5,0.5) -- (13,0.5) -- (13.65,1.25) -- (13.15,1.25) -- (12.5,0.5);
   	\end{tikzpicture}
   	\caption[Architecture of a traditional convolutional neural network.]{The architecture of the original convolutional neural network, as introduced by LeCun et al. (1989), alternates between convolutional layers including hyperbolic tangent non-linearities and subsampling layers. In this illustration, the convolutional layers already include non-linearities and, thus, a convolutional layer actually represents two layers. The feature maps of the final subsampling layer are then fed into the actual classifier consisting of an arbitrary number of fully connected layers. The output layer usually uses softmax activation functions.}
   	\label{fig:traditional-convolutional-network}
\end{figure}
 
\end{document}

% https://davidstutz.de/illustrating-convolutional-neural-networks-in-latex-with-tikz/

\documentclass[twoside,11pt,a4paper]{article}
 
\usepackage[utf8]{inputenc}
\usepackage{amsmath, amssymb, latexsym}
\usepackage{sidecap}
 
\usepackage{tikz}
\usetikzlibrary{decorations.pathreplacing}
 
\begin{document}
 
\begin{SCfigure}[2\sidecaptionrelwidth][t]
   	\centering
   	\begin{tikzpicture}
   		\node at (1.5,4){\begin{tabular}{c}input image\\or input feature map\end{tabular}};
   	
   		\draw (0,0) -- (3,0) -- (3,3) -- (0,3) -- (0,0);
   		
   		\draw (2,2) -- (2.5,2) -- (2.5,2.5) -- (2,2.5) -- (2,2);
   		\draw (2,0.5) -- (2.5,0.5) -- (2.5,1) -- (2,1) -- (2,0.5);
   		\draw (1,1) -- (1.5,1) -- (1.5,1.5) -- (1,1.5) -- (1,1);
   		
   		\draw (2.5,2) -- (7,3.25);
   		\draw (2.5,2.5) -- (7,3.25);
 
   		\draw (2.5,1) -- (5.75,0.25);
   		\draw (2.5,0.5) -- (5.75,0.25);
   		
   		\draw (1.5,1.5) -- (5.5,1.25);
   		\draw (1.5,1) -- (5.5,1.25);
   		
   		\node at (5.75,4){\begin{tabular}{c}output feature maps\end{tabular}};
   		
   		\draw[fill=black,opacity=0.2,draw=black] (5.5,1.5) -- (7.5,1.5) -- (7.5,3.5) -- (5.5,3.5) -- (5.5,1.5);
   		\draw[fill=black,opacity=0.2,draw=black] (5,1) -- (7,1) -- (7,3) -- (5,3) -- (5,1);
   		\draw[fill=black,opacity=0.2,draw=black] (4.5,0.5) -- (6.5,0.5) -- (6.5,2.5) -- (4.5,2.5) -- (4.5,0.5);
   		\draw[fill=black,opacity=0.2,draw=black] (4,0) -- (6,0) -- (6,2) -- (4,2) -- (4,0);
   	\end{tikzpicture}
   	\caption[Illustration of a convolutional layer.]{Illustration of a single convolutional layer. If layer $l$ is a convolutional layer, the input image (if $l = 1$) or a feature map of the previous layer is convolved by different filters to yield the output feature maps of layer $l$.}
   	\label{fig:convolutional-layer}
\end{SCfigure}
 
\end{document}

% https://gitlab.com/tikz-goodies/tikz-goodies/-/blob/master/drawstack/stack-example.tex
\documentclass[tikz,border=10pt]{standalone}

\usepackage{drawstack}

% Use this instead if you don't want colors.
% \usepackage[nocolor]{drawstack}

\title{{\tt drawstack.sty}: Draw execution stack easily in LaTeX}
\author{Matthieu Moy}

\begin{document}
	
\begin{tikzpicture}[scale=.8]

	\stacktop{}
	\separator
	\cell{\texttt{p3}}        \cellcomL{11(GB)} \coordinate (p3) at (currentcell.east);
	\separator
	\cell{\texttt{p2}}        \cellcomL{10(GB)} \coordinate (p2) at (currentcell.east);
	\separator
	\cell{\texttt{p1}}        \cellcomL{ 9(GB)} \coordinate (p1) at (currentcell.east);
	\separator
	\cell{\texttt{@P3D.diag}} \cellcomL{ 8(GB)}
	\cell{\texttt{\footnotesize @Object.equals}} \cellcomL{ 7(GB)}
	\cell{\texttt{3(GB)}}     \cellcomL{ 6(GB)} \coordinate (T1) at (currentcell.east);
	\separator
	\cell{\texttt{@P2D.diag}} \cellcomL{ 5(GB)}
	\cell{\texttt{\footnotesize @Object.equals}} \cellcomL{ 4(GB)}
	\cell{\texttt{1(GB)}}     \cellcomL{ 3(GB)} \coordinate (T2) at (currentcell.east);
	\separator
	\cell{\texttt{\footnotesize @Object.equals}} \cellcomL{ 2(GB)}
	\cell{\texttt{null}}      \cellcomL{ 1(GB)}
	\cell[draw=none]{Stack}
	
	
	\drawstruct{(5,1)})
	\structcell{z=2,5}
	\structcell{y=2,5}
	\structcell{x=2,5}
	\structcell{.} \coordinate (O1) at (currentcell.west);
	\coordinate (O1l) at (currentcell.south);
	
	\drawstruct{(9,-3)}
	\structcell{y=1}
	\structcell{x=1}
	\structcell{.} \coordinate (O2) at (currentcell.west);
	\coordinate (O2l) at (currentcell.south);
	
	\draw[->] (p3) -- (O1);
	\draw[->] (p2) -- (O1);
	\draw[->] (p1) -- (O2);
	
	\draw[->] (O1l) .. controls (O1 |- T1) .. (T1);
	\draw[->] (O2l) .. controls (O2 |- T2) .. (T2);
	
	\draw (10,-10) node{Heap};

\end{tikzpicture}

\end{document}

% modified by +arr
% add label number to each of the circles
\documentclass[crop, border=10pt, tikz]{standalone}

\usepackage{tikz}

\begin{document}

\begin{tikzpicture}
	\foreach \x in {1,...,10} {
		\draw (\x,0) circle (0.4cm) node {\x}; % add label number
		\draw (\x,1) circle (0.4cm) node {\x}; % draw second row
	}
\end{tikzpicture}

\end{document}

% from Helmund slides
\documentclass[tikz,border=10pt]{standalone}
%\documentclass[crop, tikz]{standalone}

\usepackage{tikz}

\begin{document}

\begin{tikzpicture}[scale=.9, transform shape]
	\tikzstyle{every node} = [circle, fill=red!30]
	\node (a) at (0, 0) {A};
	\node (b) at +(0: 1.5) {B};
	\node (c) at +(60: 1.5) {C};
	\foreach \from / \to in {a/b, b/c, c/a}
		\draw [->] (\from) -- (\to);
\end{tikzpicture}

\end{document}

\documentclass[border=10]{standalone}
\usepackage{tikz}
\usetikzlibrary{positioning,shapes,arrows}


\newcommand{\symbolA}{
	% red symbol
	\tikz \draw[red] (0,0)--(0,0.2)--(0.2,0.2)--(0.2,0.4)--(0.4,0.4);
}

\newcommand{\symbolB}{
	% blue symbol
	\tikz[y={(0,-1)}] \draw[blue] (0,0)--(0,0.2)--(0.2,0.2)--(0.2,0.4)--(0.4,0.4);
}

\newcommand{\symbolC}{
	% another way to add symbols
	\begin{tikzpicture}
		\draw[fill=green] (0,0) circle (0.2cm);
	\end{tikzpicture}
}

\begin{document}

\tikzstyle{block} = [draw, fill=blue!20,  rectangle, 
    minimum height=3em, minimum width=6em]
\tikzstyle{sum} = [draw, fill=blue!20, circle, node distance=1cm]
\tikzstyle{input} = [coordinate]
\tikzstyle{output} = [coordinate]
\tikzstyle{pinstyle} = [pin edge={to-, thin, black}]

% The block diagram code is probably more verbose than necessary
\begin{tikzpicture}[auto,  node distance=2cm, >=latex']

    % We start by placing the blocks
    \node [input, name=input] {};
    \node [sum, right of=input] (sum) {};
    \node [block, right of=sum] (controller) {\symbolA};
    
    % add label to controller
     \node[above of=controller] (ctrlabel)  [yshift=-0.75cm] {Controller};
     % add arrow from label to box
    \draw[->] (ctrlabel) -- (controller);
    
    % this is option 1: adding label on top
%    \node [block, right of=controller, pin={[pinstyle] above:Disturbances},
%            node distance=3cm] (system) {\symbolB};
	% this option 2: adding label on top
    \node [block, right of=controller, node distance=3cm] (system) {\symbolB};
    % add label "Disturbances" above system
    \node[above of=system] (syslabel) [yshift=-0.75cm] {Disturbances};
    \draw[->] (syslabel) -- (system);

    % We draw an edge between the controller and system block to 
    % calculate the coordinate "u". We need it to place the measurement block. 
    \draw [->] (controller) -- node[name=u] {$u$} (system);
    \node [output, right of=system] (output) {};
    \node [block, below of=u] (measurements) {\symbolC};
    
    % add label to "measurements" block
     \node[below of=measurements] (mealabel) [yshift=0.75cm] {Measurements};
    \draw[->] (mealabel) -- (measurements);
    

    % Once the nodes are placed, connecting them is easy. 
    \draw [draw,->] (input) -- node {$r$} (sum);
    \draw [->] (sum) -- node {$e$} (controller);
    \draw [->] (system) -- node [name=y] {$y$}(output);
    \draw [->] (y) |- (measurements);
%    \draw [->] (measurements) -| node[pos=0.99] {$-$} 
%        node [near end] {$y_m$} (sum);
    \draw [->] (measurements) -|  node  [near end] {$y_m$} (sum);
    \draw (sum) node [yshift=-7, xshift=-7]  {$-$};
\end{tikzpicture}
\end{document}

% modified by +arr
% change tick color and thickness 
%\documentclass[tikz,border=15pt]{standalone}
\documentclass[crop,border=15pt]{standalone}

\usepackage{tikz}

\begin{document}

% ticks on the axes
\begin{tikzpicture}[scale=3]

	% draw the axes
	\draw[->] (-1.5,0) -- (1.5,0);
	\draw[->] (0,-1.5) -- (0,1.5);
	
	% draw the circle
	\draw (0,0) circle (1cm);
	
	% draw the ticks
	\foreach \x in {-1cm,-0.5cm,1cm}
		\draw[red,thick] (\x,-1pt) -- (\x,1pt);
	\foreach \y in {-1cm,-0.5cm,0.5cm,1cm}
		\draw[red, thick] (-1pt,\y) -- (1pt,\y);
		
\end{tikzpicture}

\end{document}

% +arr: even thinner grid

\documentclass[tikz,border=10pt]{standalone}
%\documentclass[crop, tikz]{standalone}

\usepackage{tikz}

\begin{document}
	
\begin{tikzpicture}
	\draw[step=.5cm,gray!50,very thin] (-1.4,-1.4) grid(1.4,1.4);
	\draw (-1.5,0) -- (1.5,0);
	\draw (0,-1.5) -- (0,1.5);
	\draw (0,0) circle (1cm);
\end{tikzpicture}
	
\end{document}

\documentclass[tikz,border=10pt]{standalone}
%\documentclass[crop, tikz]{standalone}

\usepackage{tikz}

\begin{document}
	
\begin{tikzpicture}
	% draw axis
	\draw (-1.5,0) -- (1.5,0);
	\draw (0,-1.5) -- (0,1.5);
	
	\draw (-1,0) .. controls (-1,0.555) and (-0.555,1) .. (0,1)
	.. controls (0.555,1) and (1,0.555) .. (1,0);
\end{tikzpicture}
	
\end{document}

\documentclass[tikz,border=10pt]{standalone}
\usepackage[margin=25mm]{geometry}
\usepackage{tikz}

%% like standalone
%\usepackage[active,tightpage]{preview}
%\PreviewEnvironment{tikzpicture}
%\setlength\PreviewBorder{5pt}%

\begin{document}

\begin{tikzpicture}
\foreach \x in{0,...,4}
{   \draw (0,\x ,4) -- (4,\x ,4);
    \draw (\x ,0,4) -- (\x ,4,4);
    \draw (4,\x ,4) -- (4,\x ,0);
    \draw (\x ,4,4) -- (\x ,4,0);
    \draw (4,0,\x ) -- (4,4,\x );
    \draw (0,4,\x ) -- (4,4,\x );
}
\end{tikzpicture}

\end{document}

% https://www.overleaf.com/learn/latex/page_size_and_margins
%
% arr: move draw to two tikz environments not document
%	change paper size with geometry
% add manual way of creating a cuboid

\documentclass{article}
\usepackage{geometry}
\geometry{
	a5paper,
	left=10mm,
	top=20mm,
} 

\usepackage{tikz}

\newcommand{\tikzcuboid}[4]{% width, height, depth, scale
	% define tikz object
	\begin{tikzpicture}[scale=#4]
		\foreach \x in {0,...,#1}
		{   \draw (\x ,0  ,#3 ) -- (\x ,#2 ,#3 );
			\draw (\x ,#2 ,#3 ) -- (\x ,#2 ,0  );
		}
		\foreach \x in {0,...,#2}
		{   \draw (#1 ,\x ,#3 ) -- (#1 ,\x ,0  );
			\draw (0  ,\x ,#3 ) -- (#1 ,\x ,#3 );
		}
		\foreach \x in {0,...,#3}
		{   \draw (#1 ,0  ,\x ) -- (#1 ,#2 ,\x );
			\draw (0  ,#2 ,\x ) -- (#1 ,#2 ,\x );
		}
	\end{tikzpicture}
}

\newcommand{\tikzcube}[2]{% length, scale
	\tikzcuboid{#1}{#1}{#1}{#2}
}


\begin{document}
	
\begin{tikzpicture}[scale=0.5]
	% manual way of creating a cuboid drawing lines
	\foreach \x in {0,...,11}
	{   \draw[gray] (\x, 0, 5 ) -- (\x, 7, 5 );
		\draw[gray] (\x, 7, 5 ) -- (\x, 7, 0 );
	}
	\foreach \x in {0,...,7}
	{   \draw[gray!75] (11, \x, 5) -- (11, \x, 0);
		\draw[gray!75] (0, \x, 5) -- (11, \x, 5);
	}
	\foreach \x in {0,...,5}
		{   \draw[gray!25]  (11, 0, \x ) -- (11, 7, \x);
			\draw[gray!25]  (0, 7, \x) -- (11, 7, \x);
	}
\end{tikzpicture}

\vspace{35pt}

\begin{tikzpicture}
	\tikzcuboid{11}{7}{5}{0.5}
\end{tikzpicture}

\vspace{20pt}

\begin{tikzpicture}
	\tikzcube{13}{0.25}
\end{tikzpicture}

\end{document}

\documentclass[margin=10pt]{standalone}
\usepackage{tikz}

\usetikzlibrary{calc, positioning}

\tikzset{
    basic/.style={draw=black,fill=white,thick,rectangle,rounded corners=20pt, align=center},
    HeatEx/.style={draw=black,fill=white,thick,circle,minimum width=1cm},
    Tank/.style={basic, minimum width=1.5cm,minimum height=3cm,text width=1.5cm},
    3Phase/.style={basic, minimum width=4cm,minimum height=1.5cm,text width=4cm},
    Reactor/.style={basic, ultra thick,minimum width=1.5cm,minimum height=4cm,text width=1.5cm},
}

\newcommand{\COOLER}[3]{
    \node[HeatEx,right=#1 of #2](#3){};
    \draw[thick,-latex] ($(#3.south east)+(3mm,0)$) to[out=170,in=-20] ($(#3.north west)+(-3mm,0)$);
}

\newcommand{\HEATER}[4]{
    \node[HeatEx,below right=#1 and #2 of #3](#4){};
    \draw[thick,-latex] ($(#4.north east)+(3mm,0)$) to[out=200,in=20] ($(#4.south west)+(-3mm,0)$);
}

\newcommand{\TANK}[4]{
    \node[Tank,right=#1 of #2](#3){#4};
}

\newcommand{\ThreeSEP}[5]{
    \node[3Phase,right=#1 of #2](#3){#4};
    \draw[thick] (#3.south) to[out=-90,in=-90, looseness=2] node[midway] (sman) {} ($(#3.south)!.5!(#3.south east)$);
    \draw[thick,->] (sman.center) --++ (0,-1cm) -- (#5);
}

\newcommand{\REACTOR}[5]{
    \node[Reactor,below right=#1 and #2 of #3](#4){#5};
}

\begin{document}
\begin{tikzpicture}
    \node (START) {Text};
    \TANK{1cm}{START}{F1}{Tanks}
    \node[below right=of F1] (W1) {Text};
    \COOLER{1cm}{F1}{C1}
    \REACTOR{1cm}{1cm}{C1}{R1}{Reactor}
    \HEATER{1cm}{1cm}{R1}{H1}
    \ThreeSEP{1cm}{H1}{S1}{Separator}{15,-12}

%Arrows    
    \draw[thick,-latex] (START.east) to (F1.west);
    \draw[thick,-latex] (F1.south) |- (W1);
    \draw[thick,-latex] (F1.east) to (C1.west);
    \draw[thick,-latex] (C1.east) -| (R1.north);
    \draw[thick,-latex] (R1.south) |- (H1.west);
    \draw[thick,-latex] (H1.east) to (S1.west);
\end{tikzpicture}
\end{document}

% +3d+foreach+function
% +arr: change paper size, add comments
%	indent plot function, space parameters
% this could be the easiest way to draw 3d objects by using plot and function

\documentclass[tikz,border=5pt]{standalone}
\usetikzlibrary{shapes.geometric}
\usepackage{tikz-3dplot}


\begin{document}

\tdplotsetmaincoords{70}{30}   % projection angle

\begin{tikzpicture}[tdplot_main_coords]
	% add axis x, y, z
	\draw[->] (0,-4,0) -- (0,4,0) node[above right] {$x$};
	\draw[->] (-4,0,0) -- (4,0,0) node[below right] {$y$};
	\draw[->] (0,0,4) -- (0,0,-4) node[below right] {$z$};
	
	% using plot function to add top and bottom of cylinder
	\draw plot[variable=\x, domain=0:360, samples=180]    ( {cos(\x)}, -1.25, {sin(\x)} );
	\draw plot[variable=\x, domain=-45:135, samples=180] ( {cos(\x)},  1.25, {sin(\x)} );
	
	% draw sides of cylinder using the angles
	\foreach \x in {135,-45} { 
		\draw ({cos(\x)},-1.25,{sin(\x)}) -- ({cos(\x)},1.25,{sin(\x)});}
	%\node (a) [draw, cylinder, shape aspect=1.8, rotate=180, minimum height=25mm, minimum width=12mm] {};

\end{tikzpicture}

\end{document}

% from Helmund slides
\documentclass[tikz,border=10pt]{standalone}
%\documentclass[crop, tikz]{standalone}

\usepackage{tikz}
\usetikzlibrary{calc,through}

\begin{document}

\begin{tikzpicture}[scale=1.2]
	% establish the coordinates for the master reference points
	\coordinate [label=left: $A$] (A) at (0, 0);
	\coordinate [label=right:$B$] (B) at (1.25, 0.25);
	
	% draw the geometries
	\draw (A) -- (B);   % line between A and B
	
	% Node D will be when we draw a circle at A (center) that passes through B
	\node (D) [draw, circle through=(B), label=left:$D$] at (A) {};
	% Node E will be when we draw a circle at B ( center) that passes through A
	\node (E) [draw, circle through=(A), label=right:$E$] at (B) {};
	
	\coordinate[label=above:$C$] (C) at (intersection 2 of D and E);
	
	\draw [red] (A) -- (C);
	\draw [red] (B) -- (C);

\end{tikzpicture}

\end{document}

% arr: add line, change color
\documentclass[tikz,border=10pt]{standalone}

\usepackage{tikz}

\begin{document}

% draw ticks
\begin{tikzpicture}
	% If you provide two numbers before the ..., the \foreach statement will use their difference for the stepping:
	\draw[gray!75] (-1,0) -- (1, 0);   % draw line
	\foreach \x in {-1,-0.5,...,1}
		\draw (\x cm,-1pt) -- (\x cm,1pt);
\end{tikzpicture}

\end{document}

% https://tex.stackexchange.com/a/55242/173708
% arr: reindent; change page size
\documentclass[border=10]{standalone}
\usepackage{tikz}
\usetikzlibrary{positioning}


\newcommand{\symbolA}{
	\tikz \draw[red] (0,0)--(0,0.2)--(0.2,0.2)--(0.2,0.4)--(0.4,0.4);
}

\newcommand{\symbolB}{
	\tikz[y={(0,-1)}] \draw[blue] (0,0)--(0,0.2)--(0.2,0.2)--(0.2,0.4)--(0.4,0.4);
}

\newcommand{\symbolC}{
	\begin{tikzpicture}
		\draw[fill=green] (0,0) circle (0.2cm);
	\end{tikzpicture}
}


\begin{document}

\begin{tikzpicture}
	\node[draw](A) at (0,0){\symbolA};
	\node[draw, right=2em of A] (B) {\symbolB};
	\node[draw, right=2em of B] (C) {\symbolC};
	\draw[-latex] (A) -- (B);
	\draw[-latex](B) -- (C);
\end{tikzpicture}

\end{document}

\documentclass[border=15pt]{standalone}
\usepackage{tikz}

\begin{document}

% {$x =\x$, }
\begin{tikzpicture}
	\foreach \x in {1,2,3} 
		 \draw (\x,0) node (0.8cm) {$x=\x$,};
\end{tikzpicture}

\end{document}

% arr: add comments, indent code
%	change cell color to gray

\documentclass[tikz,border=10pt]{standalone}
%\documentclass[crop, tikz]{standalone}

\usepackage{tikz}

\begin{document}

\begin{tikzpicture}
	[%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
	box/.style={rectangle, draw=black, thick, minimum size=1cm, fill=gray!10},
	]%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
	
	% draw boxes based on (x,y) coordinates
	\foreach \x in {0,1,...,10} {
		\foreach \y in {0,1,...,10}   
			\node[box] at (\x, \y) {}; 
	}
	
	\node[box, fill=green] at (8,8){};  
	\node[box, fill=red  ] at (5,5){};  
	\node[box, fill=blue ] at (2,2){};  

\end{tikzpicture}

\end{document}

% https://tex.stackexchange.com/a/271584/173708
% Modified by +arr for 7x7 plane, change paper size
% add comments

\documentclass[border={10}]{standalone}
\usepackage{tikz}  
\usepackage{tikz-3dplot} 

\tdplotsetmaincoords{60}{125} % view angles
\tdplotsetrotatedcoords{0}{0}{0} 

\begin{document}

\begin{tikzpicture}
    [%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
        scale=5,tdplot_rotated_coords,
        grid/.style={very thin,gray}
    ]%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

    %draw a grid in the x-y plane
    \foreach \x in {0,1,...,7}
        \foreach \y in {0,1,...,7} {
            \draw[grid] (\x,0) -- (\x,7);  % draw horizontal lines
            \draw[grid] (0,\y) -- (7,\y);  % draw vertical lines
        };
    % draw the color filled squares
    \draw[fill=blue]   (0,0,0) -- (0,1,0) -- (1,1,0) -- (1,0,0) -- cycle;
    \draw[fill=green]  (1,1,0) -- (2,1,0) -- (2,2,0) -- (1,2,0) -- cycle;

\end{tikzpicture}    
\end{document}

% https://latexdraw.com/how-to-highlight-parts-of-a-function-and-change-the-background-color-in-latex-using-tikz/
% arr: indenting code; add comments
\documentclass[dvipsnames]{standalone}

\usepackage{tikz}
\usepackage{pgfplots}
\pgfplotsset{compat = newest}

\begin{document}
\begin{tikzpicture}
	\begin{axis}
		[
			xmin = 0, xmax = 7,
			ymin = -20, ymax = 20,
			width = 8cm,
			height = 6.5cm,
			xtick distance = 1,
			ytick distance = 4,
			smooth,
			xlabel=$x$-axis,
			ylabel=$y$-axis,
			set layers,
		]
		% plot background yellowish
		\begin{pgfonlayer}{axis background}
			\fill [yellow!10] (0,-20) rectangle (7,20);
		\end{pgfonlayer}
		% superposing three curves with different thickness and colors
		\addplot[Green!20, domain = 0:7, line width=4mm] {(x-1)*(x-3)^2*(x-6)};   % very thick curve
		\addplot[Green!30, domain = 0:7, line width=2mm] {(x-1)*(x-3)^2*(x-6)}; % thick curve
		\addplot[Green, domain = 0:7, thick] {(x-1)*(x-3)^2*(x-6)};             % thin curve
	\end{axis}

\end{tikzpicture}
\end{document}

\documentclass{standalone}
\usepackage{tikz} % http://ctan.org/pkg/pgf
\usetikzlibrary{spy, backgrounds}

\begin{document}

\begin{tikzpicture} [spy using outlines={circle, magnification=8, size=2cm, connect spies, transform shape}]
	\draw[red] (2.9,0) -- (2.9,4);
	\draw[help lines] (0,0) grid (4,4);
	\draw (0,0) -- (3,3) -- (3,0);
	%   \begin{pgfonlayer}{background}
	%    \draw[red] (2.9,0) -- (2.9,4);
	%   \end{pgfonlayer}
	\spy [black] on (3,3) in node [left] at (6,5.5);
\end{tikzpicture}
\end{document}

% https://tex.stackexchange.com/a/13405/173708
\documentclass[border=15pt]{standalone}
\usepackage{tikz}
\usetikzlibrary{calc}

\begin{document}

\begin{tikzpicture}[every node/.style={draw}]

    \begin{scope}[rotate=-30]
        \node at (3,0) [draw,name=A,rectangle, minimum width=2cm,minimum height=1cm,anchor=south,label=$m_1$,transform shape] {};
        \node at (6,0) [name=B,rectangle, minimum width=1cm,minimum height=0.75cm,anchor=south,label=$m_2$,transform shape] {};
        \node at (0,0) [name=C,circle,minimum size=.8cm,transform shape] {}; % pulley

        \draw (C.north) -- ($(A.south west)!(C.north)!(A.north west)$);
        \draw ($(A.south east)!(C.north)!(A.north east)$) -- ($(B.south west)!(C.north)!(B.north west)$);
        \draw(1,0) -- (8,0);
    \end{scope}
    % draw the vertical part
    \node at (-0.4,-5) [draw,name=D,rectangle, minimum width=1cm,minimum height=2cm,anchor=south,label=right:$m_3$] {};
    \draw ($(D.north west)!(C.210)!(D.north east)$) -- (C.210)  arc [start angle=180,end angle=60,radius=0.4cm];
\end{tikzpicture}
\end{document}

\documentclass{standalone} 
\usepackage{tikz}

\begin{document}
\begin{tikzpicture}
	\draw[help lines] (0,0) grid (4,2);
	% draw a matrix table
	\node [matrix,fill=red!20,draw=blue,very thick] (my matrix) at (2,1)
	% draw four elements, each in one of the cells
	{
		\draw (0,0) circle (4mm);   & \node[rotate=10] {Hello}; \\
		\draw (0.2,0) circle (2mm); & \fill[red] (0,0) circle (3mm); \\
	};
	% draw the arrow from the origin
	\draw [very thick,->] (0,0) |- (my matrix.west);
\end{tikzpicture}
\end{document}

% https://hugoideler.com/2013/01/tikz-node-connector/
\documentclass{standalone}

\usepackage{tikz}
\usetikzlibrary{calc}
\usetikzlibrary{positioning}

\newcommand*{\connectorH}[4][]{
  \draw[#1] (#3) -| ($(#3) !#2! (#4)$) |- (#4);
}
\newcommand*{\connectorV}[4][]{
  \draw[#1] (#3) |- ($(#3) !#2! (#4)$) -| (#4);
}

\begin{document}

\begin{tikzpicture}[every node/.style={draw, minimum size=1cm, thick, fill=white}]
  \node[] (a) {A};
  \node[above right=1cm and 2cm of a] (b) {B};
  \node[below right=1cm and 2cm of a] (c) {C};

  \connectorH[->, red]{0.50}{a}{b}
  \connectorH[->, blue]{0.75}{a}{c}
\end{tikzpicture}

\end{document}

% Author: Izaak Neutelings (September 2018)
\documentclass[border=3pt,tikz]{standalone}
\usepackage{amsmath} % for \;
\usepackage{tikz}

\usepackage{xcolor}
\colorlet{myblue}{blue!70!black}
\colorlet{mylightblue}{blue!10}
\tikzset{>=latex} % for LaTeX arrow head

\begin{document}


\begin{tikzpicture}[yscale=0.8,anchor=west]
  
  % FIRST COLUMN
  \node[anchor=west,draw=myblue,fill=mylightblue,thick,rounded corners=4,inner sep=1.5pt] (L) at (0,4) {\;\strut$qq\nu\nu$\;};  
  \node (L1) at (0.5,3) {\strut$jj\nu\nu$};
  \node (L2) at (-1.5,2) {\strut bb$\nu\nu$};
  \node (L3) at (0.5,1) {\strut tt$\nu\nu$};
  \draw[->,myblue,thick] (L.south west) ++ (0.18,0) |- (L1.west);
  \draw[->,myblue,thick] (L.south west) ++ (0.18,0) |- (L2.east);
  \draw[->,myblue,thick] (L.south west) ++ (0.18,0) |- (L3.west);
  
  % SECOND COLUMN
  \begin{scope}[shift={(2.5,0)}]
    \node[draw=myblue,fill=mylightblue,thick,rounded corners=4,inner sep=1.5pt] (M) at (0,4) {\;\strut$qq\ell\ell$\;};
    \node (M1) at (0.5,3) {\strut$jj\mu\mu$};
    \node (M2) at (0.5,2) {\strut bb$\tau\tau$, b$\tau\tau$};
    \node (M3) at (0.5,1) {\strut tt$\tau\tau$};
    \draw[->,myblue,thick] (M.south west)++(0.18,0) |- (M1.west);
    \draw[->,myblue,thick] (M.south west)++(0.18,0) |- (M2.west);
    \draw[->,myblue,thick] (M.south west)++(0.18,0) |- (M3.west);
  \end{scope}
  
  % THIRD COLUMN
  \begin{scope}[shift={(5.0,0)}]
    \node[draw=myblue,fill=mylightblue,thick,rounded corners=4,inner sep=1.5pt] (R) at (0,4) {\;\strut$qq\ell\nu$\;};
    \node (R1) at (0.5,3) {\strut$jj\mu\nu$};
    \draw[->,myblue,thick] (R.south west)++(0.18,0) |- (R1.west);
  \end{scope}

\end{tikzpicture}

\end{document}

% https://wiki.physik.uzh.ch/cms/latex:example_atom
    % Author: Izaak Neutelings (July, 2017)

\documentclass{article}
\usepackage{tikz}

% colors
\definecolor{mylightred}{RGB}{255,210,210}
\definecolor{myred}{RGB}{200,100,100}
\definecolor{mydarkred}{RGB}{140,40,40}
\definecolor{mylightblue}{RGB}{220,228,255}
\definecolor{myblue}{RGB}{183,191,229}
\definecolor{mydarkblue}{RGB}{50,70,190}

% split figures into pages
\usepackage[active,tightpage]{preview}
\PreviewEnvironment{tikzpicture}
\setlength\PreviewBorder{1pt}%

\begin{document}
	
	
	
% RUTHERFORD MODEL - atom model with central charge
\begin{tikzpicture}[scale=1]
	\coordinate (O)  at (0,0);
	\draw[mylightred,fill]         (O) circle (50pt);
	\draw[mydarkred,thick]         (O) circle (50pt) node[above right=34pt] {$-Ze$};
	\fill[radius=2.0pt,mydarkblue] (O) circle node[above=2pt] {$+Ze$};
\end{tikzpicture}



% RUTHERFORD MODEL - atom model with central charge and corpuscles
\begin{tikzpicture}[scale=1]
	\coordinate (O)  at (0,0);
	\draw[myred,dashed]            (O) circle (50pt);
	\fill[radius=2.0pt,mydarkblue] (O) circle node[above=2pt] {$+Ze$};
	\fill[radius=0.8pt,mydarkred]
	( 0.20, 1.20)  circle node[above right=-1pt,scale=0.75] {$-e$}
	( 0.68, 0.67)  circle node[above right=-1pt,scale=0.75] {$-e$}
	( 1.05,-1.10)  circle node[above left =-1pt,scale=0.75] {$-e$}
	( 0.75,-0.12)  circle node[      right= 2pt,scale=0.75] {$-e$}
	( 0.21,-1.30)  circle node[above left =-1pt,scale=0.75] {$-e$}
	(-0.80, 0.60)  circle node[above left =-1pt,scale=0.75] {$-e$}
	(-0.50, 1.21)  circle node[above right=-1pt,scale=0.75] {$-e$}
	(-0.08,-0.55)  circle node[above left =-1pt,scale=0.75] {$-e$}
	(-0.58,-0.95)  circle node[above left =-1pt,scale=0.75] {$-e$}
	(-1.10,-0.20)  circle node[above left =-1pt,scale=0.75] {$-e$};
\end{tikzpicture}



% THOMSON MODEL - atom model with corpuscles (electrons) in uniformly, positively charged sphere
\begin{tikzpicture}[scale=1]
	\coordinate (O)  at (0,0);
	\draw[mylightblue,fill] (O) circle (50pt);
	\draw[mydarkblue,thick] (O) circle (50pt) node[above right=34pt] {$+Ze$};
	\fill[radius=0.8pt,mydarkred]
	( 0.20, 1.20)  circle node[above right=-1pt,scale=0.75] {$-e$}
	( 0.10, 0.30)  circle node[above right=-1pt,scale=0.75] {$-e$}
	( 0.68, 0.67)  circle node[above right=-1pt,scale=0.75] {$-e$}
	( 1.05,-1.10)  circle node[above left =-1pt,scale=0.75] {$-e$}
	( 0.75,-0.12)  circle node[      right= 2pt,scale=0.75] {$-e$}
	( 0.21,-1.30)  circle node[above left =-1pt,scale=0.75] {$-e$}
	( 0.18,-0.55)  circle node[above left =-1pt,scale=0.75] {$-e$}
	(-0.80, 0.60)  circle node[above left =-1pt,scale=0.75] {$-e$}
	(-0.50, 1.21)  circle node[above right=-1pt,scale=0.75] {$-e$}
	(-0.40, 0.05)  circle node[above left =-1pt,scale=0.75] {$-e$}
	(-0.58,-0.95)  circle node[above left =-1pt,scale=0.75] {$-e$}
	(-1.10,-0.20)  circle node[above left =-1pt,scale=0.75] {$-e$};
\end{tikzpicture}
	
	
	
\end{document}

\documentclass[border=3mm,tikz]{standalone}
%  \documentclass{scrartcl}
\usepackage{tikz}
\begin{document} 

\begin{tikzpicture}
    \node [draw,circle ] (a) { Real label}; 
    \node  at (a.60) {$\bullet$}; 
    \node [draw] at ([shift={(95:1)}]a.60) {Second label};
\end{tikzpicture}

\end{document}  

% https://tex.stackexchange.com/a/58880/173708
% set node label position more precisely
\documentclass[border=3mm,tikz]{standalone}
%\documentclass{article}
\usepackage{tikz,comment}

\begin{comment}
	You can define the direction of the label by using label=<angle>:<label text>. To specify the distance on a per node distance, you have to supply it to the label options: label={[label distance=<distance>]<angle>:<label text>}
\end{comment}

\begin{document}

\begin{tikzpicture}
	[
		every node/.style=draw,
		every label/.style=draw
	]
	\node [label={[label distance=1cm]30:label}] {Node};
\end{tikzpicture}

\end{document}

% from Helmund slides
\documentclass[tikz,border=10pt]{standalone}
%\documentclass[crop, tikz]{standalone}

\usepackage{tikz}

\begin{document}

\begin{tikzpicture}
	\tikzstyle{every node} = [draw, shape=circle];
	\node (v0) at (0:    0) {$v_0$};
	\node (v1) at (0:    1) {$v_1$};
	\node (v2) at (72:   1) {$v_2$};
	\node (v3) at (2*72: 1) {$v_3$};
	\node (v4) at (3*72: 1) {$v_4$};	
	\node (v5) at (4*72: 1) {$v_5$};
	
	% draw the edges
	\draw (v0) -- (v1);
	\draw (v0) -- (v2);
	\draw (v0) -- (v3);
	\draw (v0) -- (v4);
	\draw (v0) -- (v5);
\end{tikzpicture}

\end{document}

\documentclass[border=10pt]{standalone}
% arr: reindent
\usepackage{tikz}
\usetikzlibrary{shapes.multipart}

\begin{document}

\begin{tikzpicture}
	[
		stack/.style={rectangle split, 
			rectangle split parts=#1,
			draw, 
			anchor=center}
	]

	\node[stack=5]  {
		\nodepart{two}a
		\nodepart{three}b
		\nodepart{four}c
		\nodepart{five}d
	};
\end{tikzpicture}

\end{document}

% https://tex.stackexchange.com/a/239506/173708
\documentclass{standalone}

\usepackage{tikz}       
\usetikzlibrary{arrows, positioning, patterns, calc, decorations.pathmorphing}

\begin{document}

\tikzstyle{block} = [draw, rectangle, inner sep=6pt, minimum width=2cm, minimum height=1cm, align=center]
\tikzstyle{joint} = [draw, circle, minimum size=1em, anchor=center]
\tikzstyle{layer} = [draw, rectangle, dashed, fill=gray!20, minimum width=7cm, minimum height=8mm, align=center, anchor=center]

\begin{tikzpicture}
    [
        >=stealth, 
        auto, 
        node distance=2cm
    ]
    
    % Place nodes
    \node [block] (system) {System};
    \node [block, below=of system] (model) {Model};
    \node [layer] at ($(system)!.5!(model)$) {\textsc{Measurement}};
    \coordinate [left=of system] (infork) {};
    \coordinate [left=of infork] (input) {};
    \coordinate [right=of system] (outfork) {};
    \coordinate [right=of outfork] (output) {};
    \coordinate [above=of system] (disturbances) {};
    \node [joint, label={[inner sep=1pt]210:\tiny\(+\)}, label={[inner sep=1pt]60:\tiny\(-\)}] (sum) at (outfork|-model) {};
    \coordinate (error) at (output|-model) {};
    % Connect nodes
    \draw [->, decorate, decoration={snake, post length=1mm}] (disturbances) -- node {\(d'\)} (system);
    \draw [->] (input) -- node {\(u'\)} (system);
    \draw [->] (system) -- node {\(t'\)} (output);
    \draw [->] (model) -- node {\(y\)} (sum);
    \draw [->] (sum) -- node {\(\epsilon\)} (error);
    \draw [->] (infork) |- node [anchor=south west] {\(u\)} (model);
    \draw [->] (outfork) -| (sum.north) node [very near end] {\(t\)};
\end{tikzpicture}

\end{document}

% +arr: add circles to nodes

\documentclass[tikz, margin=3mm]{standalone}
    \usetikzlibrary{positioning, shapes.symbols}

\begin{document}
\begin{tikzpicture}
	[ 
   	node distance = 4mm and 16mm,
	   mynode/.style = {shape=signal, 
	   	signal to=west and east,
		draw, color = #1,
		text width=1.3cm, 
		align=flush center, 
		inner xsep=0mm, 
		inner ysep=2mm, 
		font=\small}
	]
	% main nodes
	\node (A) [mynode=magenta]            {Text 2};
	\node (B) [mynode=blue, below=of A]   {Text 3};
	\node (C) [mynode=teal, below=of B]   {Text 4};
	
	% coordinates for lines
	\coordinate[left=of B.west]     (in2);
	\coordinate[left=of in2]        (in1);
	\coordinate[right=of B.east]    (out1);
	\coordinate[right=of out1]      (out2);
	
	% add circles to nodes
	\draw (in1) circle (3pt);
	\draw (in2) circle (3pt);
	\draw (out1) circle (3pt);
	\draw (out2) circle (3pt);
	
	% dashed arrows
	\begin{scope}[latex-, dashed, shorten >=1mm]
		\draw[magenta] (A.west) -- + (-0.8,0) -- (in2);
		\draw[blue]     (B.west) -- (in2);
		\draw[magenta] (C.west) -- + (-0.8,0) -- (in2);
	\end{scope}
	
	\begin{scope}[-latex, dashed, shorten >=1mm]
		\draw[magenta] (A.east) -- + (0.8,0) -- (out1);
		\draw[blue]     (B.east) -- (out1);
		\draw[magenta] (C.east) -- + (0.8,0) -- (out1);
	\end{scope}
	    
	% arrows with text
	\draw[-latex] (in1) -- node[above] {Text 1} (in2);
	\draw[-latex] (out1) -- node[above] {Text 5} (out2);
	%--------------
\end{tikzpicture}
\end{document}

\documentclass[border=10pt]{standalone}
\usepackage{tikz}

\begin{document}

We are working on
\begin{tikzpicture}
	\draw (-1.5,0) -- (1.5,0);
	\draw (0,-1.5) -- (0,1.5);
\end{tikzpicture}
\end{document}

\documentclass[tikz,border=15pt]{standalone}
\usepackage{tikz}

\begin{document}

\begin{tikzpicture}
	\filldraw [gray] (0,0) circle (2pt)
	(1,1) circle (2pt)
	(2,1) circle (2pt)
	(2,0) circle (2pt);
	\draw (0,0) .. controls (1,1) and (2,1) .. (2,0);
\end{tikzpicture}

\end{document}

% https://tex.stackexchange.com/a/48596/173708
\documentclass{scrartcl}

\usepackage{tikz}
\usetikzlibrary{calc}  

% split figures into pages
\usepackage[active,tightpage]{preview}
\PreviewEnvironment{tikzpicture}
\setlength\PreviewBorder{1pt}%

\begin{document} 

% If their areas of the circle nodes represent some numbers with proportionality 
% then you need to know exactly the radius. The radius depends of minimum width 
% and of \pgflinewidth.
%
% we have : radius = (minimum width + line width) / 2  if inner sep = 0pt
%
% In the next example, I choice first minimum width=2cm then minimum width=2cm,
% line width=5mm and finally line width=5mm,minimum width=2cm-\pgflinewidth 
% with in all cases inner sep= 0 pt.
%

	
\begin{tikzpicture} 
  \draw[help lines,step=0.1,,draw=orange] (0,0) grid (8,1); 
  \draw[help lines] (0,0) grid (8,1);     
  \node[minimum width=2cm,circle,inner sep=0pt,fill=blue!20,fill opacity=.5]{};
  \node[minimum width=2cm,circle,inner sep=0pt,fill=blue!20,fill opacity=.5,
        line width=5mm,draw=gray,opacity=.5] at (3,0){}; 
  \node[circle,inner sep=0pt,fill=blue!20,,fill opacity=.5,
        line width=5mm,draw=gray,opacity=.5,minimum width=2cm-\pgflinewidth]  at (6,0) {}; 
\end{tikzpicture}  

% Now if I want to get three circles with areas equal to pi, 2pi and 3pi 
% I created a macro `def\lw{2mm}` to change quickly the line width in all nodes

\tikzset{myrad/.style 2 args={circle,inner sep=0pt,minimum width=(2*(sqrt(#1)*1 cm ) - \pgflinewidth,fill=#2,draw=#2,fill opacity=.5,opacity=.8}}    

\begin{tikzpicture} 
	\def\lw{2mm}
	\draw[help lines,step=0.1,,draw=orange] (0,0) grid (8,1); 
	\draw[help lines] (0,0) grid (8,1);     
	\node[line width=\lw,myrad={1}{blue!20}]  at (0,0) {1}; 
	\node[line width=\lw,myrad={2}{red!20}]  at (3,0) {2};
	\node[line width=\lw, myrad={3}{green!20}]  at (7,0) {3};   
\end{tikzpicture}  

% Finally If you want nodes with areas equal to 1 cm^2, 2 cm^2 and 3 cm^2 : 
% I change the line width for the second group of nodes

\begin{tikzpicture} 
	\def\lw{2mm}
	\draw[help lines,step=0.1,,draw=orange] (0,0) grid (8,1); 
	\draw[help lines] (0,0) grid (8,1);     
	\node[line width=\lw,myrad={1}{blue!20}]  at (0,0) {1}; 
	\node[line width=\lw,myrad={2}{red!20}]  at (3,0) {2};
	\node[line width=\lw, myrad={3}{green!20}]  at (7,0) {3};   
\end{tikzpicture}    

\begin{tikzpicture} 
	\def\lw{5mm}
	\draw[help lines,step=0.1,,draw=orange] (0,0) grid (8,1); 
	\draw[help lines] (0,0) grid (8,1);     
	\node[line width=\lw,myrad={1}{blue!20}]  at (0,0) {1}; 
	\node[line width=\lw,myrad={2}{red!20}]  at (3,0) {2};
	\node[line width=\lw, myrad={3}{green!20}]  at (7,0) {3};   
\end{tikzpicture}

%To avoid this kind of problem, we can use circles instead of circle nodes. But we need to adjust the radius wit the pgflinewidth. In the next example,I want a radius = 2cm so I need to use : radius=2cm-0.5\pgflinewidth. Then I need to create a node with the same dimensions.
%
%Like the question about node and rectangle here, we can associate a node to the shape The main problem : we can't use scale but it's more easy to place a label.

\tikzset{set node/.style={insert path={% 
	\pgfextra{% 
		\node[inner sep=0pt,outer sep = 0pt,draw=black, % draw= none only to show what I do
		circle,
		minimum width=2*\pgfkeysvalueof{/tikz/x radius}+0.5\pgflinewidth](#1) {};
}}}}

\begin{tikzpicture}
	\draw[help lines] (-3,-3) grid (3,3);
	\draw[blue,line width=5mm,opacity=.2] (0,0) circle [radius=2cm-0.5\pgflinewidth,set node=C1]  ; 
	\draw[thick,->] (3,-3) -- (C1.east);
\end{tikzpicture}

\end{document} 

%\documentclass{standalone}
\documentclass[tikz,border=15pt]{standalone}
%\documentclass[crop, tikz]{standalone}

\usepackage{tikz}
\usetikzlibrary{shapes}

\begin{document}
	
\tikzset{my node/.style={trapezium, fill=#1!20, draw=#1!75, text=black}}

\begin{tikzpicture}
	\tikzset{trapezium stretches=true}
	
	\draw [help lines] grid (3,2);
	
	% draw trapeziums
	\node [my node=red] {A};
	\node [my node=green, minimum height=1.5cm] at (1, 1.25) {B};
	\node [my node=blue, minimum width=1.5cm] at (2, 0) {C};
\end{tikzpicture}
	
\end{document}

% http://blog.jakob-wankel.de/2017/01/25/drawing-a-mechanical-system-with-tikz-in-latex/
\documentclass[border=15pt]{standalone}

\usepackage{tikz}
\usetikzlibrary{calc,patterns,decorations.pathmorphing,decorations.markings}


\begin{document}

\begin{tikzpicture}
	\tikzstyle{spring}=[thick,decorate,decoration={zigzag,pre length=0.3cm,post length=0.3cm,segment length=6}]
	\tikzstyle{damper}=[thick,decoration={markings,  
		mark connection node=dmp,
		mark=at position 0.5 with 
		{
			\node (dmp) [thick,inner sep=0pt,transform shape,rotate=-90,minimum width=15pt,minimum height=3pt,draw=none] {};
			\draw [thick] ($(dmp.north east)+(2pt,0)$) -- (dmp.south east) -- (dmp.south west) -- ($(dmp.north west)+(2pt,0)$);
			\draw [thick] ($(dmp.north)+(0,-5pt)$) -- ($(dmp.north)+(0,5pt)$);
		}
	}, decorate]
	\tikzstyle{ground}=[fill,pattern=north east lines,draw=none,minimum width=0.75cm,minimum height=0.3cm]

	\node (M) [draw,outer sep=0pt,thick,minimum width=1cm, minimum height=2cm] {$m_1$};
	\node (M2) [draw,outer sep=0pt,thick,minimum width=1cm, minimum height=2cm] at (2,0) {$m_2$};
	\node (M3) [draw,outer sep=0pt,thick,minimum width=1cm, minimum height=2cm] at (4,0) {$m_3$};
	\node (M4) [draw,outer sep=0pt,thick,minimum width=1cm, minimum height=2cm] at (6,0) {$m_4$};

	\node (ground) [ground,anchor=north,xshift=3cm,yshift=-0.25cm,minimum width=9.5cm] at (M.south) {};

	\draw (ground.north east) -- (ground.north west);
	\draw [thick] (M.south west) ++ (0.2cm,-0.125cm) circle (0.125cm)  (M.south east) ++ (-0.2cm,-0.125cm) circle (0.125cm);
	\draw [thick] (M2.south west) ++ (0.2cm,-0.125cm) circle (0.125cm)  (M2.south east) ++ (-0.2cm,-0.125cm) circle (0.125cm);
	\draw [thick] (M3.south west) ++ (0.2cm,-0.125cm) circle (0.125cm)  (M3.south east) ++ (-0.2cm,-0.125cm) circle (0.125cm);
	\draw [thick] (M4.south west) ++ (0.2cm,-0.125cm) circle (0.125cm)  (M4.south east) ++ (-0.2cm,-0.125cm) circle (0.125cm);

	\draw [spring] (M2.220) -- ($(M.north east)!(M.220)!(M.south east)$);
	\draw [spring] (M3.220) -- ($(M2.north east)!(M2.220)!(M2.south east)$);
	\draw [spring] (M4.220) -- ($(M3.north east)!(M3.220)!(M3.south east)$);

	\draw [damper] (M2.170) -- ($(M.north east)!(M2.170)!(M.south east)$);
	\draw [damper] (M3.170) -- ($(M2.north east)!(M3.170)!(M2.south east)$);
	\draw [damper] (M4.170) -- ($(M3.north east)!(M4.170)!(M3.south east)$);

	\node at (1,.8) {$d_1$};
	\node at (3,.8) {$d_2$};
	\node at (5,.8) {$d_3$};

	\node at (1,-.8) {$k_1$};
	\node at (3,-.8) {$k_2$};
	\node at (5,-.8) {$k_3$};

\end{tikzpicture}

\end{document}

% https://tex.stackexchange.com/a/240917/173708
\documentclass[tikz,border=10pt]{standalone}
\usepackage{tikz}

\usetikzlibrary{arrows,calc,decorations.pathmorphing,positioning,decorations.markings}

\tikzset{
    % build the shaded rectangle
    shadedrec/.style={
        rectangle,
        draw=black,
        top color=gray,        % this is part of the shade
        bottom color=white,    % this is part of the shade
        shading angle={135},   % this is part of the shade
        text width=3cm,
        inner sep=1em,
        rounded corners=1.2ex,
        very thick,
        text centered},
    snake arrow/.style={
        decorate,
        decoration={zigzag,amplitude=3mm,segment length=5mm,post length=0mm}},
    damper/.style={
        very thick,
        decoration={markings,  
        mark connection node=dmp,
        mark=at position 0.5 with 
        {
            \node (dmp) [very thick,transform shape,text width=.3cm,rotate=-90,minimum height=3pt,draw=none, fill=black,outer xsep=2pt, outer ysep=1pt] {};
            \draw [very thick] ($(dmp.north east)+(-.6pt,0)$) -- ($(dmp.south east)+(-.6pt,0)$) -- ($(dmp.south west)+(-.6pt,0)$) -- ($(dmp.north west)+(-.6pt,0)$);
            \draw [very thick,rotate=-90] ($(dmp.north)+(0,-5pt)$) -- ($(dmp.north)+(0,5pt)$);
        }
    }, decorate}
}

\begin{document}
\pagestyle{empty}

\begin{tikzpicture}
    % Shapes
    \node[shadedrec, anchor=center] (S1) at (4,3) {$M$};
    \node[shadedrec, anchor=center, below=2 of S1] (S2) {$m$};

    %Nodes side
    \node[anchor=center,text centered,right=2cm of S1.east] (sm) {Sprung mass};
    \node[below=of sm] (susp) {Suspension};
    \node[below=of susp] (usm) {Unsprung mass};
    \node[below=of usm] {Tire};

    % Paths

    %side arrows
    \draw[->,very thick] (S1.west) -- ++ (-1.5,0) -- ++ (0,-1.5) node[below] {$Z$};
    \draw[->,very thick] (S2.west) -- ++ (-1.5,0) -- ++ (0,-1.5) node[below] {$Z_u$};

    %zigzag lines
    \draw[very thick, snake arrow] ($(S1.south west)!.5!(S1.south)$) -- ++ (0,-2) node[left,midway,xshift=-1em] {$K_s$};
    \draw[very thick, snake arrow] (S2.south) -- ++ (0,-2) 
        node[left,midway,xshift=-1em] {$K_t$};

    %Connector shape
    \draw[damper] ($(S2.north east)!.5!(S2.north)$) -- ($(S1.south east)!.5!(S1.south)$) node[right,midway,xshift=1em] {$C_s$};

    % Road
    \coordinate (A) at ($(S2.west)+(5.5,-2.45)$);
    \draw[->,very thick] (A) -- ++(-7,0) -- ++ (0,-1.5) node[below] {$Z_r$};

    \begin{scope}[shift={($(S2.west)+(-1.5,-2.45)$)}]
        \foreach \x in {0.5,1,...,7} { %This one draws the little diagonal lines
        \draw (\x,0) -- ({\x-.5},-.5);
        }
    \end{scope} 
\end{tikzpicture}

\end{document}

% https://tex.stackexchange.com/a/13952/173708
\documentclass[border=15pt]{standalone}
\usepackage{tikz}
\usetikzlibrary{calc,patterns,decorations.pathmorphing,decorations.markings}

\begin{document}

\begin{tikzpicture}[every node/.style={draw,outer sep=0pt,thick}]
  \tikzstyle{spring}=[thick,decorate,decoration={zigzag,pre length=0.3cm,post length=0.3cm,segment length=6}]
  \tikzstyle{damper}=[thick,decoration={markings,  
    mark connection node=dmp,
    mark=at position 0.5 with 
    {
      \node (dmp) [thick,inner sep=0pt,transform shape,rotate=-90,minimum width=15pt,minimum height=3pt,draw=none] {};
      \draw [thick] ($(dmp.north east)+(2pt,0)$) -- (dmp.south east) -- (dmp.south west) -- ($(dmp.north west)+(2pt,0)$);
      \draw [thick] ($(dmp.north)+(0,-5pt)$) -- ($(dmp.north)+(0,5pt)$);
    }
  }, decorate]

  \tikzstyle{ground}=[fill,pattern=north east lines,draw=none,minimum width=0.75cm,minimum height=0.3cm]

  \node (M) [minimum width=3.5cm,minimum height=2cm] {mass, $m$};

  \node (ground1) at (M.south) [ground,yshift=-1.5cm,xshift=-1.25cm,anchor=north] {};
  \draw (ground1.north west) -- (ground1.north east);
  \draw [spring] (ground1.north) -- ($(M.south east)!(ground1.north)!(M.south west)$);

  \node (ground2) at (M.south) [ground,yshift=-1.5cm,anchor=north] {};
  \draw (ground2.north west) -- (ground2.north east);
  \draw [damper] (ground2.north) -- ($(M.south east)!(ground2.north)!(M.south west)$);

  \node (ground3) at (M.south) [ground,yshift=-1.5cm,xshift=1.25cm,anchor=north] {};
  \draw (ground3.north west) -- (ground3.north east);
  \draw [spring] (ground3.north) -- ($(M.south east)!(ground3.north)!(M.south west)$);

  \draw [-latex,ultra thick] (M.north) ++(0,0.2cm) -- +(0,1cm);

  \begin{scope}[xshift=7cm]
    \node (M) [minimum width=1cm, minimum height=2.5cm] {$m$};

    \node (ground) [ground,anchor=north,yshift=-0.25cm,minimum width=1.5cm] at (M.south) {};
    \draw (ground.north east) -- (ground.north west);
    \draw [thick] (M.south west) ++ (0.2cm,-0.125cm) circle (0.125cm)  (M.south east) ++ (-0.2cm,-0.125cm) circle (0.125cm);

    \node (wall) [ground, rotate=-90, minimum width=3cm,yshift=-3cm] {};
    \draw (wall.north east) -- (wall.north west);

    \draw [spring] (wall.170) -- ($(M.north west)!(wall.170)!(M.south west)$);
    \draw [damper] (wall.10) -- ($(M.north west)!(wall.10)!(M.south west)$);

    \draw [-latex,ultra thick] (M.east) ++ (0.2cm,0) -- +(1cm,0);
  \end{scope}
\end{tikzpicture}

\end{document}

% http://www.texample.net/tikz/examples/airfoil-profiles/
% Read airfoils from data files
% Airfoil profiles from the UIUC Airfoil Coordinates Database
% http://www.ae.uiuc.edu/m-selig/ads/coord_database.html
% Data is released under the GNU General Public Licence. See
% http://www.ae.uiuc.edu/m-selig/pd/gpl.html for more details. 
\documentclass{standalone}

\usepackage{tikz}
\usepackage{verbatim}

\begin{comment}
:Title: Airfoil profiles
:Tags: Plots, External file, Foreach

A few airfoil profiles from the extensive `UIUC Airfoil Coordinates Database`_. The data
is provided in a convenient x,y coordinate format suitable for plotting using PGF/TikZ's
``plot file`` construct.

Note that the data is released under the `GNU General Public License`_. To use the
data files with PGF/TikZ, you have to comment out the lines not containing coordinates.

Download the airfoils used in the example: `airfoildata.zip`_

.. _UIUC Airfoil Coordinates Database: http://www.ae.uiuc.edu/m-selig/ads/coord_database.html
.. _GNU General Public License: http://www.ae.uiuc.edu/m-selig/pd/gpl.html
.. _airfoildata.zip: http://www.fauskes.net/media/pgftikzexamples/data/airfoildata.zip
\end{comment}

\begin{document}

\newcounter{y}
\setcounter{y}{0}

\begin{tikzpicture}
    % read all the data files. Don't set the data folder here
    % read the label \lbl and the filename \fn with the for loop
    \foreach \lbl / \fn in {EPPLER 625/e625.dat,
                            WORTMANN FX 2/fx2.dat,
                            EPPLER 664 (EXTENDED)/e664ex.dat,
                            CLARK Y/clarcy.dat,
                            Eiffel 10 (Wright)/eiffel10.dat,
                            FX 69-PR-281/fx69pr281.dat,
                            NACA Munk M-4 airfoil/m4.dat}
    {
        % Some profiles look better when using plot[smooth]
        \draw[yshift=-\arabic{y}cm,scale=3] node[left=0.5cm] {\lbl}
        % set the data folder in the next line
        plot file{data/\fn} -- cycle;
        \stepcounter{y}
    }
\end{tikzpicture}

\end{document}

% https://tex.stackexchange.com/a/20500/173708
\documentclass{standalone}
% arr: reindenting
\usepackage{tikz}
\usepackage{pgfplotstable}

\begin{document}
\centering
\begin{tikzpicture}
	\pgfplotstableread{./data/circles.dat}\table   % read the data table
	\pgfplotstablegetrowsof{\table}
	\pgfmathsetmacro{\M}{\pgfplotsretval-1}
	\pgfplotstablegetcolsof{\table}
	\pgfmathsetmacro{\N}{\pgfplotsretval-1}
	
	\foreach \row in {0,...,\M}{       % read the table rows
		\foreach \col in {0,...,\N}{   % read the columns
			\pgfplotstablegetelem{\row}{[index]\col}\of\table
			\ifnum\col=0
				\xdef\x{\pgfplotsretval}
			\fi
			\ifnum\col=1
				\xdef\y{\pgfplotsretval}
			\fi
			\ifnum\col=2
				\xdef\radius{\pgfplotsretval}
			\fi
		}
		\definecolor{mycolor}{RGB}{
			\pdfuniformdeviate 256,%
			\pdfuniformdeviate 256,%
			\pdfuniformdeviate 256}
		\fill[mycolor,opacity=.5] (\x,\y)circle(\radius cm);
	}
\end{tikzpicture}
\end{document}

% http://pgfplots.net/media/tikz/examples/TEX/plot-markers.tex
\documentclass[border=10pt]{standalone}
%%%<
\usepackage{verbatim}
\usepackage{pgfplots}
\pgfplotsset{width=7cm, compat=1.8, grid style={dashed}}

\begin{comment}
:Title: Markers in a line diagram
:Tags: 2D;Markers
:Author: Elke Schubert
:Slug: plot-markers

Besides x and y values, special markers illustrate the result.

This topic was discussed on: http://texwelt.de/wissen/fragen/3363/

Data file
-------
if you want the data to be saved as you modify this file, add this above the comments:

	\usepackage{filecontents}
	
	% changes in this table make changes to CSV file
	\begin{filecontents}{data.csv}
	measuring   power1   result1   power2   result2
	1           2        0.2       3.5      0.39
	2           3        0.35      3.8      0.3
	3           4        0.45      7.9      0.35
	4           5        0.5       8.5      0.39
	5           6        0.65      8.0      0.38
	6           7        0.68      8.5      0.4
	7           8        0.7       9.5      0.41
	8           7.5      0.73      10.5     0.99
	9           6.7      0.75      {}       {}
	10          10       0.79      {}       {}
	\end{filecontents}
	%%%>

\end{comment}

\begin{document}
\begin{tikzpicture}
  \begin{axis}
    [
      scatter,
      scatter src = explicite,
      grid        = major, % draws coordinate grid
      xlabel      = Force $\lbrack{}$ F $\rbrack$, 
      ylabel      = Amperage $\lbrack{}$ kA $\rbrack$,
      width       = \linewidth,
      height      = 10cm,
      xmin = 0, xmax = 15,
      ymin = 0, ymax = 12,
    ]
    \addplot+ [
      visualization depends on =
        {10*\thisrow{result1} \as \perpointmarksize},
      scatter/@pre marker code/.append style =
        {/tikz/mark size = \perpointmarksize},
    ]
    % read the table
    % read the column result1
    table[x=measuring, y=power1, point meta=\thisrow{result1}] {./data/data.csv};
    \addplot+ [
      visualization depends on =
        {10*\thisrow{result2} \as \perpointmarksize},
      scatter/@pre marker code/.append style =
        {/tikz/mark size = \perpointmarksize}
    ]
    % read the column result2
    table [x=measuring, y=power2, point meta=\thisrow{result2}] {./data/data.csv};
    \fill [gray, fill opacity=0.25] (axis cs:5,0) rectangle (axis cs:7,12);
  \end{axis}
\end{tikzpicture}
\end{document}

\documentclass[border=10pt]{standalone}

\usepackage{pgfplots}
\pgfplotsset{compat=newest}

\begin{document}

% Preamble: \pgfplotsset{width=7cm,compat=newest}
\begin{tikzpicture}
    \begin{axis}
	    [
			height=9cm,
			width=9cm,
			grid=major,
	    ]
	    % \addplot gnuplot[id=filesuffix]{(-x**5 - 242)};
	    \addlegendentry{model}
		    
		    \addplot coordinates {
			    (-4.77778,2027.60977)
			    (-3.55556,347.84069)
			    (-2.33333,22.58953)
			    (-1.11111,-493.50066)
			    (0.11111,46.66082)
			    (1.33333,-205.56286)
			    (2.55556,-341.40638)
			    (3.77778,-1169.24780)
			    (5.00000,-3269.56775)
			    };
		    \addlegendentry{estimate}
	    \end{axis}
    \end{tikzpicture}

\end{document}

\documentclass{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat=1.11}

\begin{document}
\begin{tikzpicture}
    \begin{axis}
        \addplot table {./data/coordinates.dat};
    \end{axis}
\end{tikzpicture}
\end{document}

% http://pgfplots.net/media/tikz/examples/TEX/graph-in-table.tex
% arr: reindent
\documentclass[border=10pt]{standalone}
%%%<
\usepackage{verbatim}

\begin{comment}

Data file
-------
if you want the data to be saved as you modify this file, add this above comments:

	\usepackage{filecontents}
	
	\begin{filecontents}{./data/data.txt}
	name z p mean lci uci
	Afear -0.96  0.33 -0.42 -1.28 0.49
	Anofear 0.09 0.93 0.04 -0.85 0.94
	B+2 0.29 0.78 0.10 -0.59 0.79
	B+1   0.84  0.40  0.30 -0.40 1.00 
	B1:1   2.19  0.03  0.80 0.08 1.52 
	B-1   1.02  0.31  0.37 -0.33 1.07 
	B-2   -0.10  0.92  -0.03 -0.72 0.65 
	C+2   -1.11  0.27  -0.30 -0.83 0.23 
	C+1   1.15   0.25  0.32 -0.22 0.86 
	C1:1   -1.34  0.18  -0.38 -0.93 0.17 
	C-1   0.43  0.67  0.12 -0.42 0.66 
	C-2   -0.37  0.71  -0.10 -0.63 0.43 
	D+2   0.41  0.68  0.12 -0.44 0.67 
	D+1   -0.69  0.49  -0.20 -0.77 0.37 
	D1:1   -1.33  0.18  -0.39 -0.97 0.19 
	D-1   -1.21  0.23  -0.35 -0.92 0.22 
	D-2   0.32  0.75  0.09 -0.46 0.65 
	\end{filecontents}
	%%%>
\end{comment}


\usepackage{pgfplots}
\pgfplotsset{compat=1.8}
\usepackage{pgfplotstable}
\usepackage{booktabs}
\usepackage{multirow}

\begin{comment}
:Title: Graph within a table
:Tags: 2D;PGFPlotstable;Styles
:Author: Jake
:Slug: graph-in-table

We would like to plot a graph within a table column, similar to
http://texample.net/tikz/examples/weather-stations-data/ .

We will use the booktabs package for good table design,
and the multirow package.

The data is read using PGFPlotstable and the plot is typeset dynamically.

This code was written by Jake on TeX.SE.
\end{comment}

% Read data file, create new column ``upper CI boundary - mean''
\pgfplotstableread{./data/data.txt}\data
\pgfplotstableset{create on use/error/.style={
    create col/expr={\thisrow{uci}-\thisrow{mean}
    }
  }
}

% Define the command for the plot
\newcommand{\errplot}{%
  \begin{tikzpicture}[trim axis left,trim axis right]
    \begin{axis}[y=-\baselineskip,
        scale only axis,
        width             = 6.5cm,
        enlarge y limits  = {abs=0.5},
        axis y line*      = middle,
        y axis line style = dashed,
        ytick             = \empty,
        axis x line*      = bottom
      ]
      % ``mean'' must be present in the datafile,
      %``error'' is the newly generated column
      \addplot+[only marks][error bars/.cd,x dir=both, x explicit]
        table [x=mean,y expr=\coordindex,x error=error]{\data};
    \end{axis}
  \end{tikzpicture}%
}

\begin{document}
% Get number of rows in datafile
\pgfplotstablegetrowsof{\data}
\let\numberofrows=\pgfplotsretval

% Print the table
\pgfplotstabletypeset
  [
    columns={name,error,z,p,mean,ci},
    % Booktabs rules
    every head row/.style = {before row=\toprule, after row=\midrule},
    every last row/.style = {after row=[3ex]\bottomrule},
    % Set header name
    columns/name/.style = {string type, column name=Name},
    % Use the ``error'' column to call the \errplot command in a multirow cell
    % in the first row, keep empty for all other rows
    columns/error/.style = {
      column name = {},
      assign cell content/.code = {% use \multirow for Z column:
      \ifnum\pgfplotstablerow=0
        \pgfkeyssetvalue{/pgfplots/table/@cell content}
        {\multirow{\numberofrows}{6.5cm}{\errplot}}%
      \else
        \pgfkeyssetvalue{/pgfplots/table/@cell content}{}%
      \fi
      }
    },
    % Format numbers and titles
    columns/mean/.style = {column name = Mean, fixed ,fixed zerofill, dec sep align},
    columns/z/.style    = {column name = $z$, fixed, fixed zerofill, dec sep align},
    columns/p/.style    = {column name = $p$, fixed, fixed zerofill, dec sep align},
    columns/ci/.style   = {string type, column name = 95\% CI},
    % Create the ``(x to y)'' format, use \pgfmathprintnumber with `showpos`
    % to make things align nicely
    create on use/ci/.style={
    create col/assign/.code={\edef\value{(
      \noexpand\pgfmathprintnumber[showpos,fixed,fixed zerofill]{\thisrow{lci}}
      to \noexpand\pgfmathprintnumber[showpos,fixed,fixed zerofill]{\thisrow{uci}})}
      \pgfkeyslet{/pgfplots/table/create col/next content}\value
      }
    }
  ]
{\data}
\end{document}

% https://tex.stackexchange.com/a/457351/173708
\documentclass[border=10pt]{standalone}
\usepackage{verbatim}


\begin{comment}

Data file
-------
if you want the data to be saved as you modify this file, add this:

\usepackage{filecontents}

\begin{filecontents*}{events.csv}
X,Y,Event,Date
0,0,Abbotsford,January 1
3,0,Surrey,April 1
5,1,Vancouver,June 1
6,0,New\ Westminster,July 1
10,0,North\ Vancouver,November 1
0.75,4,Ended\ High\ School,Jan 26
3.3,4,Started\ Trade\ School,April 10
5.8,4,Ended\ Trade\ School,June 28
8,4,Started\ Job\ 1,Sept 1
10.8,4,Started\ Job\ 2,Nov 27
\end{filecontents*}
%%%>
\end{comment}

\usepackage{tikz}
\usepackage{pgfplotstable}
\pgfplotstableread[col sep=comma]{./data/events.csv}\data  %  in ./data folder
% from https://tex.stackexchange.com/a/445369/121799
\newcommand*{\ReadOutElement}[4]{%
    \pgfplotstablegetelem{#2}{#3}\of{#1}%
    \let#4\pgfplotsretval
}


%only necessary for overset
\usetikzlibrary{positioning}
\usepackage{makecell}%
\usetikzlibrary{patterns}

\begin{document}

\begin{tikzpicture}[node distance =2mm]

   % draw horizontal line
   \draw (0,0) coordinate (baseLine) -- (11,0);

   % draw vertical lines and label below with months
   \foreach \varXcoord/\varMonth [count=\xx] in {
      0/Jan,
      1/Feb,
      2/Mar,
      3/Apr,
      4/May,
      5/Jun,
      6/Jul,
      7/Aug,
      8/Sep,
      9/Oct,
      10/Nov,
      11/Dec
   }
      \draw (\varXcoord,3pt) -- +(0,-6pt) node (qBaseTick\xx) [below] {\varMonth};

   \fill [pattern=north west lines, pattern color=yellow] (-1,0) rectangle (12.5,4); 

   \node [above left = 2.5 and 1 of baseLine,rotate=90] 
   {
   Location
   };

   \fill [pattern=north west lines, pattern color=orange] (-1,4) rectangle (12.5,8); 

   \node [above left = 7 and 1 of baseLine,rotate=90] 
   {
   Career
   };

   \pgfplotstablegetrowsof{\data}
   \pgfmathtruncatemacro{\rownumber}{\pgfplotsretval-1}
   \foreach \X in {0,...,\rownumber}
   {
         \ReadOutElement{\data}{\X}{X}{\varXcoord}
         \ReadOutElement{\data}{\X}{Y}{\varYcoord}
         \ReadOutElement{\data}{\X}{Event}{\varEvent}
         \ReadOutElement{\data}{\X}{Date}{\varDate}
         \draw[<-] (\varXcoord,0) -- (\varXcoord,\varYcoord+0.5);
         \node [above right = \varYcoord and \varXcoord + 0.5 of baseLine, rotate=45, anchor=south west] {\makecell[l]{\small${\varEvent}$\\\tiny \varDate}};
   }
\end{tikzpicture}

\end{document}

% Diagram of Android activity life cycle
% Author: Pavel Seda 
\documentclass[border=10pt]{standalone}
%%%<
\usepackage{verbatim}
%%%>
\begin{comment}
:Title: Diagram of Android activity life cycle
:Tags: Diagrams;Flowcharts;Charts;Styles;Computer science
:Author: Pavel Seda
:Slug: android

A flow diagram of an Android activity life cycle.
It uses basic nodes and arrows and defines node styles.
\end{comment}
\usepackage{tikz}
\usetikzlibrary{arrows.meta}

\tikzset{%
  >={Latex[width=2mm,length=2mm]},
  % Specifications for style of nodes:
            base/.style = {rectangle, rounded corners, draw=black,
                           minimum width=4cm, minimum height=1cm,
                           text centered, font=\sffamily},
  activityStarts/.style = {base, fill=blue!30},
       startstop/.style = {base, fill=red!30},
    activityRuns/.style = {base, fill=green!30},
         process/.style = {base, minimum width=2.5cm, fill=orange!15,
                           font=\ttfamily},
}
\begin{document}    
% Drawing part, node distance is 1.5 cm and every node
% is prefilled with white background
\begin{tikzpicture}[node distance=1.5cm,
      every node/.style={fill=white, font=\sffamily}, align=center]
    % Specification of nodes (position, etc.)
    \node (start)             [activityStarts]              {Activity starts};
    \node (onCreateBlock)     [process, below of=start]          {onCreate()};
    \node (onStartBlock)      [process, below of=onCreateBlock]   {onStart()};
    \node (onResumeBlock)     [process, below of=onStartBlock]   {onResume()};
    \node (activityRuns)      [activityRuns, below of=onResumeBlock]
                                                        {Activity is running};
    \node (onPauseBlock)      [process, below of=activityRuns, yshift=-1cm]
                                                                  {onPause()};
    \node (onStopBlock)       [process, below of=onPauseBlock, yshift=-1cm]
                                                                  {onStop()};
    \node (onDestroyBlock)    [process, below of=onStopBlock, yshift=-1cm] 
                                                                {onDestroy()};
    \node (onRestartBlock)    [process, right of=onStartBlock, xshift=4cm]
                                                                {onRestart()};
    \node (ActivityEnds)      [startstop, left of=activityRuns, xshift=-4cm]
                                                          {Process is killed};
    \node (ActivityDestroyed) [startstop, below of=onDestroyBlock]
                                                      {Activity is shut down};     
    % Specification of lines between nodes specified above
    % with aditional nodes for description 
    \draw[->]             (start) -- (onCreateBlock);
    \draw[->]     (onCreateBlock) -- (onStartBlock);
    \draw[->]      (onStartBlock) -- (onResumeBlock);
    \draw[->]     (onResumeBlock) -- (activityRuns);
    \draw[->]      (activityRuns) -- node[text width=4cm]
                                    {Another activity comes in
                                      front of the activity} (onPauseBlock);
    \draw[->]      (onPauseBlock) -- node {The activity is no longer visible}
                                    (onStopBlock);
    \draw[->]       (onStopBlock) -- node {The activity is shut down by
                                    user or system} (onDestroyBlock);
    \draw[->]    (onRestartBlock) -- (onStartBlock);
    \draw[->]       (onStopBlock) -| node[yshift=1.25cm, text width=3cm]
                                    {The activity comes to the foreground}
                                    (onRestartBlock);
    \draw[->]    (onDestroyBlock) -- (ActivityDestroyed);
    \draw[->]      (onPauseBlock) -| node(priorityXMemory)
                                    {higher priority $\rightarrow$ more memory}
                                    (ActivityEnds);
    \draw           (onStopBlock) -| (priorityXMemory);
    \draw[->]     (ActivityEnds)  |- node [yshift=-2cm, text width=3.1cm]
                                      {User navigates back to the activity}
                                      (onCreateBlock);
    \draw[->] (onPauseBlock.east) -- ++(2.6,0) -- ++(0,2) -- ++(0,2) --                
      node[xshift=1.2cm,yshift=-1.5cm, text width=2.5cm]
      {The activity comes to the foreground}(onResumeBlock.east);
  \end{tikzpicture}
\end{document}

% Direction-of-arrival diagram
% Author: Edgar Fuentes
\documentclass{article}
\usepackage{tikz}
%%%<
\usepackage{verbatim}
\usepackage[active,tightpage]{preview}
\PreviewEnvironment{tikzpicture}
\setlength\PreviewBorder{10pt}%
%%%>
\begin{comment}
:Title: Direction-of-arrival diagram
:Tags: Diagrams;Styles;
:Author: Edgar Fuentes
:Slug: doa-diagram

This diagram explains a spatial filter with direction of arrival estimation.
\end{comment}
\usetikzlibrary{shapes.geometric}
\usetikzlibrary{shapes.arrows}
\usepackage{array}

\begin{document}
\begin{tikzpicture} [
    auto,
    decision/.style = { diamond, draw=blue, thick, fill=blue!20,
                        text width=5em, text badly centered,
                        inner sep=1pt, rounded corners },
    block/.style    = { rectangle, draw=blue, thick, 
                        fill=blue!20, text width=10em, text centered,
                        rounded corners, minimum height=2em },
    line/.style     = { draw, thick, ->, shorten >=2pt },
  ]
  % Define nodes in a matrix
  \matrix [column sep=5mm, row sep=10mm] {
                    & \node [text centered] (x) {$\mathbf{X}$};            & \\
                    & \node (null1) {};                                    & \\
                    & \node [block] (doa) {\textsf{DoAE}($\mathbf{X}$)};   & \\
   			 		\node(null3){}; & \node [decision] (uiddes)
                        {\textsf{UID}($\hat{\mathbf{X}}$)};
                                  & \node[text centered](tra){$\mathbf{i}$}; \\
                    & \node [block] (track) {\textsf{DoAT}($\mathbf{x}$)}; & \\
                    & \node [block] (pesos)
                        {\textsf{BF}(DoA$_{\mathrm{T}}$,DoAs)};            & \\
                    & \node [block] (filtrado)
                        {\textsf{SF}($\mathbf{w}$,$\mathbf{x}$)};          & \\
                    & \node [text centered] (xf) {$\hat{x}(t)$ };          & \\
  };
  % connect all nodes defined above
  \begin{scope} [every path/.style=line]
    \path (x)        --    (doa);
    \path (doa)      --    node [near start] {DoAs} (uiddes);
    \path (tra)      --    (uiddes);
    \path (uiddes)   --++  (-3,0) node [near start] {no} |- (null1);
    \path (uiddes)   --    node [near start] {DoA} (track);
    \path (track)    --    node [near start] {DoA$_{\mathrm{T}}$} (pesos);
    \path (pesos)    --    node [near start] {\textbf{w}} (filtrado);
    \path (filtrado) --    (xf);
  \end{scope}
  %
  % legend for subprocedures
  \node (leyend) at (7.5, 5){
    \begin{tabular}{>{\sffamily}l@{: }l}
      \multicolumn{2}{c}{\textbf{subprocedures}} \\
      DoAE & direction of arrival estimation     \\
      UID  & user identification                 \\
      DoAT & DoA tracking                        \\
      BF   & beam forming                        \\
      SF   & spatial filtering
    \end{tabular}
  };
  %
  % legend for input and output variables
  \node (leyend) at (7, 0){
    \begin{tabular}{l@{: }l}
      \multicolumn{2}{c}{\textbf{variables}}              \\
      DoA                       & direction of arrival    \\
      $\mathbf{i}$              & identification sequence \\
      $\mathbf{X},\,\mathbf{x}$ & signal model            \\
      DoA$_{\mathrm{T}}$        & DoAs up to date         \\
      $\hat{x}(t)$              & fitered signal
      \end{tabular}
  };
\end{tikzpicture}
\end{document}

% Flowcharting techniques for easy maintenance
% Author: Brent Longborough
\documentclass[x11names]{article}
\usepackage{tikz}
\usetikzlibrary{shapes,arrows,chains}
%%%<
\usepackage{verbatim}
\usepackage[active,tightpage]{preview}
\PreviewEnvironment{tikzpicture}
\setlength\PreviewBorder{5mm}%
%%%>
\begin{comment}
:Title: Easy-maintenance flowchart
:Tags: flowcharts
:Author: Brent Longborough
:Slug: flexible-flow-chart

  This TikZ example illustrates a number of techniques for making TikZ
  flowcharts easier to maintain:
    * Use of <on chain> and <on grid> to simplify positioning
    * Use of global <node distance> options to eliminate the need to 
      specify individual inter-node distances
    * Use of <join> to reduce the need for references to node names
    * Use of <join by> styles to tailor specific connectors
    * Use of <coordinate> nodes to provide consistent layout for
      parallel flow lines
    * A method for consistent annotation of decision box exits
    * A technique for marking coordinate nodes (for layout debugging)

    I encourage you to tinker at this file - add intermediate boxes,
    alter the global distance settings, and so on, to see how well (or
    ill!) it adapts.
\end{comment}
\begin{document}
% =================================================
% Set up a few colours
\colorlet{lcfree}{Green3}
\colorlet{lcnorm}{Blue3}
\colorlet{lccong}{Red3}
% -------------------------------------------------
% Set up a new layer for the debugging marks, and make sure it is on
% top
\pgfdeclarelayer{marx}
\pgfsetlayers{main,marx}
% A macro for marking coordinates (specific to the coordinate naming
% scheme used here). Swap the following 2 definitions to deactivate
% marks.
\providecommand{\cmark}[2][]{%
  \begin{pgfonlayer}{marx}
    \node [nmark] at (c#2#1) {#2};
  \end{pgfonlayer}{marx}
  } 
\providecommand{\cmark}[2][]{\relax} 
% -------------------------------------------------
% Start the picture
\begin{tikzpicture}[%
    >=triangle 60,              % Nice arrows; your taste may be different
    start chain=going below,    % General flow is top-to-bottom
    node distance=6mm and 60mm, % Global setup of box spacing
    every join/.style={norm},   % Default linetype for connecting boxes
    ]
  % ------------------------------------------------- 
  % A few box styles 
  % <on chain> *and* <on grid> reduce the need for manual relative
  % positioning of nodes
  \tikzset{
    base/.style={draw, on chain, on grid, align=center, minimum height=4ex},
    proc/.style={base, rectangle, text width=8em},
    test/.style={base, diamond, aspect=2, text width=5em},
    term/.style={proc, rounded corners},
    % coord node style is used for placing corners of connecting lines
    coord/.style={coordinate, on chain, on grid, node distance=6mm and 25mm},
    % nmark node style is used for coordinate debugging marks
    nmark/.style={draw, cyan, circle, font={\sffamily\bfseries}},
    % -------------------------------------------------
    % Connector line styles for different parts of the diagram
    norm/.style={->, draw, lcnorm},
    free/.style={->, draw, lcfree},
    cong/.style={->, draw, lccong},
    it/.style={font={\small\itshape}}
  }
  % -------------------------------------------------
  % Start by placing the nodes
  \node [proc, densely dotted, it] (p0) {New trigger message thread};
  % Use join to connect a node to the previous one 
  \node [term, join]      {Trigger scheduler};
  \node [proc, join] (p1) {Get quota $k > 1$};
  \node [proc, join]      {Open queue};
  \node [proc, join]      {Dispatch message};
  \node [test, join] (t1) {Got msg?};
  % No join for exits from test nodes - connections have more complex
  % requirements
  % We continue until all the blocks are positioned
  \node [proc] (p2) {$k \mathbin{{-}{=}} 1$};
  \node [proc, join] (p3) {Dispatch message};
  \node [test, join] (t2) {Got msg?};
  \node [test] (t3) {Capacity?};
  \node [test] (t4) {$k \mathbin{{-}{=}} 1$};
  % We position the next block explicitly as the first block in the
  % second column.  The chain 'comes along with us'. The distance
  % between columns has already been defined, so we don't need to
  % specify it.
  \node [proc, fill=lcfree!25, right=of p1] (p4) {Reset congestion};
  \node [proc, join=by free] {Set \textsc{mq} wait flag};
  \node [proc, join=by free] (p5) {Dispatch message};
  \node [test, join=by free] (t5) {Got msg?};
  \node [test] (t6) {Capacity?};
  % Some more nodes specifically positioned (we could have avoided this,
  % but try it and you'll see the result is ugly).
  \node [test] (t7) [right=of t2] {$k \mathbin{{-}{=}} 1$};
  \node [proc, fill=lccong!25, right=of t3] (p8) {Set congestion};
  \node [proc, join=by cong, right=of t4] (p9) {Close queue};
  \node [term, join] (p10) {Exit trigger message thread};
  % -------------------------------------------------
  % Now we place the coordinate nodes for the connectors with angles, or
  % with annotations. We also mark them for debugging.
  \node [coord, right=of t1] (c1)  {}; \cmark{1}   
  \node [coord, right=of t3] (c3)  {}; \cmark{3}   
  \node [coord, right=of t6] (c6)  {}; \cmark{6}   
  \node [coord, right=of t7] (c7)  {}; \cmark{7}   
  \node [coord, left=of t4]  (c4)  {}; \cmark{4}   
  \node [coord, right=of t4] (c4r) {}; \cmark[r]{4}
  \node [coord, left=of t7]  (c5)  {}; \cmark{5}   
  % -------------------------------------------------
  % A couple of boxes have annotations
  \node [above=0mm of p4, it] {(Queue was empty)};
  \node [above=0mm of p8, it] {(Queue was not empty)};
  % -------------------------------------------------
  % All the other connections come out of tests and need annotating
  % First, the straight north-south connections. In each case, we first
  % draw a path with a (consistently positioned) annotation node, then
  % we draw the arrow itself.
  \path (t1.south) to node [near start, xshift=1em] {$y$} (p2);
    \draw [*->,lcnorm] (t1.south) -- (p2);
  \path (t2.south) to node [near start, xshift=1em] {$y$} (t3); 
    \draw [*->,lcnorm] (t2.south) -- (t3);
  \path (t3.south) to node [near start, xshift=1em] {$y$} (t4); 
    \draw [*->,lcnorm] (t3.south) -- (t4);
  \path (t5.south) to node [near start, xshift=1em] {$y$} (t6); 
    \draw [*->,lcfree] (t5.south) -- (t6);
  \path (t6.south) to node [near start, xshift=1em] {$y$} (t7); 
    \draw [*->,lcfree] (t6.south) -- (t7); 
  % ------------------------------------------------- 
  % Now the straight east-west connections. To provide consistent
  % positioning of the test exit annotations, we have positioned
  % coordinates for the vertical part of the connectors. The annotation
  % text is positioned on a path to the coordinate, and then the whole
  % connector is drawn to its destination box.
  \path (t3.east) to node [near start, yshift=1em] {$n$} (c3); 
    \draw [o->,lccong] (t3.east) -- (p8);
  \path (t4.east) to node [yshift=-1em] {$k \leq 0$} (c4r); 
    \draw [o->,lcnorm] (t4.east) -- (p9);
  % -------------------------------------------------
  % Finally, the twisty connectors. Again, we place the annotation
  % first, then draw the connector
  \path (t1.east) to node [near start, yshift=1em] {$n$} (c1); 
    \draw [o->,lcfree] (t1.east) -- (c1) |- (p4);
  \path (t2.east) -| node [very near start, yshift=1em] {$n$} (c1); 
    \draw [o->,lcfree] (t2.east) -| (c1);
  \path (t4.west) to node [yshift=-1em] {$k>0$} (c4); 
    \draw [*->,lcnorm] (t4.west) -- (c4) |- (p3);
  \path (t5.east) -| node [very near start, yshift=1em] {$n$} (c6); 
    \draw [o->,lcfree] (t5.east) -| (c6); 
  \path (t6.east) to node [near start, yshift=1em] {$n$} (c6); 
    \draw [o->,lcfree] (t6.east) -| (c7); 
  \path (t7.east) to node [yshift=-1em] {$k \leq 0$} (c7); 
    \draw [o->,lcfree] (t7.east) -- (c7)  |- (p9);
  \path (t7.west) to node [yshift=-1em] {$k>0$} (c5); 
    \draw [*->,lcfree] (t7.west) -- (c5) |- (p5);
  % -------------------------------------------------
  % A last flourish which breaks all the rules
  \draw [->,MediumPurple4, dotted, thick, shorten >=1mm]
    (p9.south) -- ++(5mm,-3mm)  -- ++(27mm,0) 
    |- node [black, near end, yshift=0.75em, it]
      {(When message + resources available)} (p0);
  % -------------------------------------------------
\end{tikzpicture}
% =================================================
\end{document}

% https://github.com/FriendlyUser/LatexDiagrams
\documentclass{standalone}

\usepackage{tikz}
\usetikzlibrary{arrows.meta,
                calc, chains,
                quotes,
                positioning,
                shapes.geometric}

\begin{document}

\begin{tikzpicture}[
    node distance = 8mm and 16mm,
      start chain = A going below,
      base/.style = {draw, minimum width=32mm, minimum height=8mm,
                     align=center, on chain=A},
 startstop/.style = {base, rectangle, rounded corners, fill=red!30},
   process/.style = {base, rectangle, fill=orange!30},
        io/.style = {base, trapezium, 
                     trapezium left angle=70, trapezium right angle=110,
                     fill=blue!30},
  decision/.style = {base, diamond, fill=green!30},
  every edge quotes/.style = {auto=right}]
                    ]
  \node [startstop]       {Read Video};            % <-- A-1
  \node [process]         {Extract Frames};
  \node [io]              {Read Frame};
  \node [decision]        {Completed?};
  \node [process]         {Save Watermarked Video};
  \node [process]         {Stop};             % <-- A-6
  %
  \node [process,                             % <-- A-7
        right=of A-4]    {Get Next Frame};
  %%
  \draw [arrows=-Stealth] 
      (A-1) edge["read data"]          (A-2)
      (A-2) edge["get watermark"]    (A-3)
      (A-3) edge[text width=3cm,"apply watermark to all frames "]       (A-4)
      (A-4) edge["yes"]            (A-5)
      (A-5) edge["exit"]          (A-6)
      (A-4) edge["no"']          (A-7)       % <-- by ' is swapped label position
      (A-7) |- ($(A-2.south east)!0.5!(A-3.north east)$)
            -| ([xshift=7mm] A-3.north)
      ;
  \end{tikzpicture}
\end{document}

% Schema of Labs on a class
% Author: Cristo J. Alanis
\documentclass[11pt]{article}
\usepackage{tikz} 
%%%<
\usepackage{verbatim}
\usepackage[active,tightpage]{preview}
\PreviewEnvironment{tikzpicture}
\setlength\PreviewBorder{5pt}%
%%%>
\begin{comment}
:Title: Schema of Labs on a class
:Tags: Shadows;Styles;Backgrounds;Diagrams
:Author: Cristo J. Alanis
:Slug: labs-schema

Listado de pr\'acticas
\end{comment}
\usetikzlibrary{shadows,arrows}
% Define the layers to draw the diagram
\pgfdeclarelayer{background}
\pgfdeclarelayer{foreground}
\pgfsetlayers{background,main,foreground}
 
% Define block styles  
\tikzstyle{materia}=[draw, fill=blue!20, text width=6.0em, text centered,
  minimum height=1.5em,drop shadow]
\tikzstyle{practica} = [materia, text width=8em, minimum width=10em,
  minimum height=3em, rounded corners, drop shadow]
\tikzstyle{texto} = [above, text width=6em, text centered]
\tikzstyle{linepart} = [draw, thick, color=black!50, -latex', dashed]
\tikzstyle{line} = [draw, thick, color=black!50, -latex']
\tikzstyle{ur}=[draw, text centered, minimum height=0.01em]
 
% Define distances for bordering
\newcommand{\blockdist}{1.3}
\newcommand{\edgedist}{1.5}

\newcommand{\practica}[2]{node (p#1) [practica]
  {Pr\'actica #1\\{\scriptsize\textit{#2}}}}

% Draw background
\newcommand{\background}[5]{%
  \begin{pgfonlayer}{background}
    % Left-top corner of the background rectangle
    \path (#1.west |- #2.north)+(-0.5,0.5) node (a1) {};
    % Right-bottom corner of the background rectanle
    \path (#3.east |- #4.south)+(+0.5,-0.25) node (a2) {};
    % Draw the background
    \path[fill=yellow!20,rounded corners, draw=black!50, dashed]
      (a1) rectangle (a2);
    \path (a1.east |- a1.south)+(0.8,-0.3) node (u1)[texto]
      {\scriptsize\textit{Unidad #5}};
  \end{pgfonlayer}}

\newcommand{\transreceptor}[3]{%
  \path [linepart] (#1.east) -- node [above]
    {\scriptsize Transreceptor #2} (#3);}

\begin{document}
\begin{tikzpicture}[scale=0.7,transform shape]
 
  % Draw diagram elements
  \path \practica {1}{Diferencias en componentes electr\'onicos};
  \path (p1.south)+(0.0,-1.0) \practica{2}{Serie de Fourier};
  \path (p2.south)+(-2.5,-1.5) \practica{3}{Antena para HF};
  \path (p3.south)+(0.0,-1.0) \practica{5}{Medidor de SWR};
  \path (p3.south)+(5.0,-1.0) \practica{4}{Amplificador para HF};

  \path (p4.south)+(-2.5,-1.5) \practica{6}{Oscilador de RF};
  \path (p6.south)+(-2.5,-1.25) \practica{7}{Modulador AM};
  \path (p6.south)+(2.5,-1.25) \practica{8}{Demodulador AM};
  \path (p8.east)+(+5.5,0) node (ur1)[ur] {};

  \path (p7.south)+(0.0,-1.5) \practica{9}{Codificador digital};
  \path (p8.south)+(0.0,-1.5) \practica{10}{Decodificador digital};
  \path (p10.east)+(+5.5,0) node (ur2)[ur] {};
  \path (p9.south)+(0.0,-1.5) \practica{11}{Codificador FDM};
  \path (p10.south)+(0.0,-1.5) \practica{12}{Decodificador FDM};
  \path (p12.east)+(+5.5,0) node (ur3)[ur] {};
  \path (p11.south)+(0.0,-1.5) \practica{13}{Codificador SSTV};
  \path (p12.south)+(0.0,-1.5) \practica{14}{Decodificador SSTV};
  \path (p14.east)+(+5.5,0) node (ur4)[ur] {};
  \path (p14.south)+(-2.5,-1.5) \practica{15}{Conmutaci\'on telef\'onica};
  \path (p15.south)+(0.0,-1.0) \practica{16}{Telfon\'ia celular an\'aloga};
  \path (p16.south)+(0.0,-1.5) \practica{17}{Receptor de  telemetr\'ia}; 
  \path (p17.south)+(0.0,-1.5) \practica{18}{Gu\'ias de ondas};
     
  % Draw arrows between elements
  \path [line] (p1.south) -- node [above] {} (p2);

  \path [line] (p2.south) -- +(0.0,-0.5) -- +(-2.5,-0.5)
    -- node [above, midway] {} (p3);
  \path [line] (p3.south) -- node [above] {} (p5) ;
     
  \path [line] (p2.south) -- +(0.0,-0.5) -- +(+2.5,-0.5)
    -- node [above, midway] {} (p4);
  \path [linepart] (p3.east) -- +(+0.5,-0.0) -- +(+0.5,-1.75)
    -- node [left, midway] {} (p4);
  \path [linepart] (p3.east) -- +(+0.5,-0.0) -- +(+0.5,-1.75)
    -- node [left, midway] {} (p4);

  \path [line] (p4.south) -- +(0.0,-0.5) -- +(-2.5,-0.5)
    -- node [above, midway] {} (p6);
  \path [line] (p5.south) -- +(0.0,-0.5) -- +(+2.5,-0.5)
    -- node [above, midway] {} (p6);     
  \path [linepart] (p2.east) -- +(2.75,0.0) -- +(2.75,-5.85)
    -- node [right] {} (p6);
  \path [line] (p6.south) -- +(0.0,-0.25) -- +(-2.5,-0.25)
    -- node [above, midway] {} (p7);
  \path [line] (p6.south) -- +(0.0,-0.25) -- +(+2.5,-0.25)
    -- node [above, midway] {} (p8);
  \path [linepart] (p7.east) -- node [left] {} (p8);
  \transreceptor{p8}{AM banda 40m}{ur1}

  \path [line] (p7.south) -- node [above] {} (p9) ;
  \path [line] (p8.south) -- node [above] {} (p10) ;
  \path [linepart] (p9.east) -- node [left] {} (p10);
  \transreceptor{p10}{CW}{ur2}
  \path [line] (p9.south) -- node [above] {} (p11) ;
  \path [line] (p10.south) -- node [above] {} (p12) ;
  \path [linepart] (p11.east) -- node [left] {} (p12);
  \transreceptor{p12}{FDMDV}{ur3}

  \path [line] (p11.south) -- node [above] {} (p13) ;
  \path [line] (p12.south) -- node [above] {} (p14) ;
  \path [linepart] (p13.east) -- node [left] {} (p14);   
  \transreceptor{p14}{SSTV}{ur4}

  \path [line] (p14.south) -- +(0.0,-0.5) -- +(-2.5,-0.5)
    -- node [above, midway] {} (p15);
  \path [line] (p13.south) -- +(0.0,-0.5) -- +(+2.5,-0.5)
    -- node [above, midway] {} (p15);
  \path [line] (p15.south) -- node [above] {} (p16) ;     
  \path [line] (p16.south) -- node [above] {} (p17) ;
  \path [line] (p17.south) -- node [above] {} (p18) ;
   
  \background{p3}{p1}{p4}{p2}{I}
  \background{p3}{p3}{p4}{p5}{II}
  \background{p3}{p6}{p4}{p7}{III}
  \background{p3}{p9}{p4}{p10}{IV}
  \background{p3}{p11}{p4}{p12}{V}
  \background{p3}{p13}{p4}{p14}{VI}
  \background{p3}{p15}{p4}{p16}{VII}
  \background{p3}{p17}{p4}{p17}{VIII}
  \background{p3}{p18}{p4}{p18}{IX}
\end{tikzpicture}
\end{document}