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RPNPro

Official Description

RPNPro is a calculator for software engineers.

RPNPro uses RPN (Reverse Polish Notation) as an input scheme. It is based on the same four level stack model as provided by the original HP (Hewlett-Packard) calculators, featuring X, Y, Z and T registers.

The contents of the X register are always shown in decimal, hexadecimal and binary notation.