kalk

Kalk is a calculator (both program and library) that supports user-defined variables and functions.

Features

Operators: +, -, *, /, !
Groups: (), ⌈⌉, ⌋⌊
Pre-defined functions and constants
User-defined functions and variables. f(x, y) = xy, x = 5
Understands fairly ambiguous syntax. Eg. 2sin50 + 2xy
Syntax highlighting
Special-symbol completion on tab. Eg. write sqrt and press tab. It will be turned into √.