Mathomatic is a portable, command-line computer algebra system (CAS) written entirely in the C programming language. It is free and open source software (FOSS), published under the GNU Lesser General Public License (LGPL version 2.1). The software can automatically solve, differentiate, simplify, combine, and compare algebraic equations, perform standard, complex number, and polynomial arithmetic, etc. It does some calculus and is very easy to compile, learn, and use.
Mathomatic consists of a text-mode, floating point and symbolic math application and library suitable for desktops, handhelds, and embedded systems. It compiles and runs under any operating system with a C compiler, including Linux, Unix, Mac OS X, and MS-Windows. An operating system is not required for using the symbolic math library, and there are no dependencies other than the standard C libraries. The mathematical results should always be correct, simple, and beautiful; if not, please report it to the developers.