Projects / Orpie


Orpie is a fullscreen RPN calculator for the console. Its operation is similar to that of modern HP calculators, but data entry has been optimized for efficiency on a PC keyboard. Features include extensive scientific calculator functionality, units support, base conversions, command completion, configurable keybindings, and a visible interactive stack.

Operating Systems

Recent releases

  •  14 Sep 2007 12:28

    Release Notes: This release is compatible with OCaml 3.10.0. Some minor bugs have been fixed.

    •  13 Sep 2007 08:13

      Release Notes: The unit handling subsystem has been completely rewritten, enabling the creation of user-defined units and physical constants. The code base has been updated for compatibility with recent releases of GSL.

      •  30 Oct 2005 07:58

        Release Notes: This release has a bugfix for the crash caused by executing uconvert() with only one element on the stack.

        •  22 Sep 2005 04:42

          Release Notes: The build script has been updated to improve compatibility with platforms such as FreeBSD and Mac OS X.

          •  17 Sep 2004 13:51

            Release Notes: A potential C library linking error has been corrected, and the build script supports parallel make once again.

            Recent comments

            07 Mar 2014 13:31 parrotbsd

            This program is exactly what I needed. It's so much easier just to pull up a terminal than to go digging around for one of HP calculators. If you like RPN, this is a no brainer download :)

            05 Mar 2012 21:35 yamad

            Still the best desktop calculator I have found. One of the first things I install on any new OS install. Thanks!

            08 Aug 2010 00:26 beisenberg

            Orpie is by far the best calculator available for unix systems. There's nothing even remotely close.

            22 Dec 2006 11:13 pelzlpj

            Re: Outstanding!

            > It would rock if someone did an embedded version !

            For what it's worth, Orpie does have a pretty clean separation between the UI code and the underlying calculator object. The calculator object can be imported into other OCaml code pretty easily; there's an example of this in .

            25 Nov 2006 11:00 abaababa

            Re: Outstanding!

            > Orpie is the program I've been trying to

            > get time to write. Now I don't have to!

            > Thanks for bringing a console rpn

            > calculator that behaves like an HP

            > calculator. I've always liked my

            > HP48GX, now I have a version I can use

            > anywhere!



            I totally agree. It's the only decent calculator that can do complex arithmetic and linear algebra over ssh, short of a mathematics package. Very clean, very nice. It would rock if someone did an embedded version !

            Of course, it is written in Ocaml - what else ?


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