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RPN Calculators


Solar Energy


Torphichen Kirk

RPN or "Reverse Polish Notation" is a more natural way of performing calculations than the more conventional "=" sign calculators. The general principle of use is to type in a number, click "ENTER", type in another number and then click on the two-number operation you want to perform. Unfortunately, very few calculators use this method. My first RPN calculator was an HP 45 purchased by the company I worked for in the early 1970's - it cost over 400 - at that time you could get a reasonable second-hand car for that. Like many people, I much prefer to use RPN, and so I have built my own RPN calculator to use on my PC.

This is written in Visual Basic and runs on most 32 bit Windows platforms, (I still use XP). It incorporates a number of features that I like to have:
  • Undo and Redo, for easy recovery if you make a mistake;
  • Cartesian to Polar number conversion, (and vice-versa);
  • All the computation stack registers are visible so that you know what numbers you are working with;
  • Alterable number base (including fractional number bases), (2.0 to 32.0) - try doing circular geometry calculations to the base Pi;
  • You can adjust the number of significant figures displayed;
  • 5 predefined number display formats: "Engineer" where the exponent is always a multiple of 3, "Money" where there are always two digits after the point; "Integer" obvious; "Exponent" also obvious; and "Free" which uses the decimal format where possible and the exponent form otherwise.
  • Hyperbolic functions;
  • Cut and paste so that you can transfer numbers between the calculator and other applications.

If you want to try this calculator, you can download it here . When you first start it, you get a short delay before you can use it. The delay will increase gradually each time you use it unless you register it with me. All I ask is five pounds, dollars or euros. Email me to arrange payment via PayPal. I welcome any feedback.

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This page last updated on 2013-08-08 JGM