rpCalc – Python based RPN calculator

rpCalc is a simple, graphical open source, RPN (Reverse Polish Notation) calculator.

The software works much like an HP calculator, and all of the commands can be entered using the keyboard or a mouse.

If you know how to use an RPN calculator (like some Hewlett-Packard models), you know how to use rpCalc. It stores previous results in four registers (usually labeled X, Y, Z and T), and the numbers are entered before the operators.

rpCalc started out as a very small program written to try out various Python GUI toolkits, but has evolved into a functional and useful utility.

rpCalc requires Python (version 3.4 or higher), Qt (version 5.4 or higher), and PyQt (version 5.4 or higher).

Features include:

  • Uses reverse polish notation, similar to most Hewlett-Packard calculators.
  • The number, operator or command text on any key can be typed, or the mouse can be used to hit the key.
  • The four RPN registers can optionally be output in the main display.
  • A separate window can display the four RPN registers, a history of recent calculations, or the contents of the ten memory registers.
  • A separate window converts to and from other number bases (hexadecimal, octal and binary).
  • Any values from the extra windows can be copied to the calculator display or to the clipboard.
  • Engineering notation display option was added that only shows exponents that are divisible by three.
  • Copy Value button that copies the value of the current input mode base to the clipboard for use in other applications.
  • Options can be set to control the display of numbers and the initial window configuration.
  • Option to remove the LCD display highlight. This is useful for smaller displays.

Website: rpcalc.bellz.org
Support: Documentation
Developer: Douglas W. Bell
License: GNU GPL v2 or any later version


rpCalc is written in Python. Learn Python with our recommended free books and free tutorials.

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