Would really like to see a comparison between this and Soulver (http://www.acqualia.com/soulver/). Most obvious differences are the lack of a two-column view and support for Markdown, as well as support for function definitions, which I'm pretty sure Soulver lacks.

Calca takes ideas from Soulver and super sizes them:

* Soulver allows free text editing within a line of computation; Calca allows free editing in the entire file

* Both update as you type

* Soulver understands arithmetic; Calca knows algebra, calculus, and algorithms

* Soulver requires that all variables be defined; Calca does not

* Soulver does not support user defined functions; to Calca, everything is a function

* Soulver has no programming constructs; Calca is one step away from being a general purpose programming language.

* Soulver does not support matrices; Calca does

One feature that Soulver has that I would love to see in Calca is combinatorics - you can do x choose y in Soulver.

Developer here, yep that was a bad omission. The worst part is I do that kind of math all the time! You can count on it showing up in updates either as a function or as syntax.

Maybe someone reading this would be interested in my own calculator? Not as fancy as Calca for sure, by it can do functions...

https://github.com/prog-re/klak

I would love to have this with Python syntax (possibly with support of numpy and scipy).

Have you seen the IPython Notebook?

http://ipython.org/notebook.html

I think it does what you want

Wow! This seems amazingly complete for an iOS/OS X-only app that I've never heard of before today. Is it based on some preexisting algebra system, or totally from scratch? Regardless, it's very impressive.

It's from scratch C# code using Xamarin to build the UI layers for iOS/OS X. Well, I also use a parser generator jayc which is based on jay which is a yacc cc. Everything else is mine. It's a pretty standard Expression tree implementation with a symbolic interpreter.

Awesome product, I just bought it for my iPhone. Given that it's C# already, any plans for a windows version? I often do these types of calculations in excel at work, but this would be so handy.

See previous discussion at:

https://news.ycombinator.com/item?id=6015148

And yet no Soulver for Windows... wink