Calctus

Calctus (カルクタス) is a calculator application for Windows developed for engineers.

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Overview

• Syntax highlighting and auto-completion.
• Decimal, hexadecimal, and binary numbers can be mixed.
• SI prefixes, datetime formats, RGB color representation and several other formats are also available.
• The formula history can be modified, and the calculation results are immediately regenerated.
• Built-in constants and built-in functions. Constants and functions can also be user-defined.
• Numerical solution of equations by Newton's method.

Features

Numeric Representations

Operators

Variables

Variables can be assigned using the equal sign.

a = 2 [Return]
b = 3 [Return]
a * b [Return] // --> Calctus answers 6.

Constants

User-defined constants can also be used.

Embedded Functions

User Defined Function

User functions can be defined using the def keyword.

def f(x) = x^2
f(3) // --> Calctus answers 9.

External Script Call as Functions

Calctus can call scripts such as Python as functions.

Function arguments are passed to the script as command line arguments, and the standard output of the script is returned to Calctus.

1. Open the Scripts tab in the Calctus Settings dialog.
2. Check Enable External Script Functions.
3. If you want to specify the folder where you want to place the scripts, click the Change button to specify the folder.
4. Click the Open button. If asked if you want to create the folder, click Yes.
5. Place a python script add.py like the following in the folder.

   import sys
   a = float(sys.argv[1])
   b = float(sys.argv[2])
   print(a + b)

6. After closing the settings dialog, the add function is now available.

If you wish to use a scripting language other than Python, please register the extension and interpreter in the Scripts tab of the Settings dialog.

Solve Function (Newton-Raphson method)

Use the solve keyword to solve equations numerically by Newton's method.

solve(x^2=2,x) // --> Calctus answers [-1.414213562, 1.414213562].

By default, the Newton's method is performed based on automatically generated initial values. Therefore, it may produce inaccurate results if the solution is concentrated in a small area or exists far from the origin.

In such cases, the 3rd argument can be given an initial value.

solve(sin(x),x,314) // --> Calctus answers 314.159265359.

That initial value can also be given as an array.

solve(sin(x),x,[-314,314]) // --> Calctus answers [-314.159265359, 314.159265359].

By providing the 3rd and 4th arguments at the same time, a range of initial values can be specified. In this case, 101 values between these ranges are used as initial values.

solve(sin(x),x,-5,5) // --> Calctus answers [-3.141592654, 0, 3.141592654].

⚠️ Note that the solution obtained using the solve keyword is an approximation and does not necessarily correspond to the analytical solution.

Part-selection

Verilog-style part selection is available for arrays and scalar values.

array=[1,2,3]
array[1]   // --> Calctus answers 2.
array[1]=5 // --> Calctus answers [1, 5, 3].

x=0x1234
x[11:4]      // --> Calctus answers 0x23.
x[11:4]=0xab // --> Calctus answers 0x1ab4.

Omission of Opening Parentheses

The opening parenthesis at the beginning of a line can be omitted.

1+2)*3 // --> Calctus answers 9.

Auto-Completion

Exponent Adjustment🆕

Exponent-part of E-notation and SI prefix can be adjusted using Alt + Arrow keys.

Assertion

RPN Operations

If only an operator is entered, the expression is "popped" from the history and combined with that operator.

If you use RPN operation, it is recommended to turn off the automatic input of "ans" in the settings.

1 [Return]
2 [Return]
+ [Return] // --> "1" and "2" replaced with "1+2"
3 [Return]
4 [Return]
+* [Return] // --> "1+2", "3" and "4" replaced with "(1+2)*(3+4)"

Graph Plotting 🆕

The plot keyword can be used to draw a graph.

⚠️ This feature is experimental and may be removed in future versions.

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