Yacas

YACAS is an easy to use, general purpose Computer Algebra System, a program for
symbolic manipulation of mathematical expressions. It uses its own programming
language designed for symbolic as well as arbitrary-precision numerical
computations. The system has a library of scripts that implement many of the
symbolic algebra operations; new algorithms can be easily added to the library.
YACAS comes with extensive documentation (320+ pages) covering the scripting
language, the functionality that is already implemented in the system, and the
algorithms we used.
This entire site (including the documentation) can also be found in the source
code distribution.


**************
Update version.
Please run it from shell