GNU Octave - GNU Octave is a programming language for scientific computing.
MATLAB - A high-level language and interactive environment for numerical computation, visualization, and programming
Wolfram Mathematica - Mathematica has characterized the cutting edge in specialized processing—and gave the chief calculation environment to a large number of pioneers, instructors, understudies, and others around the globe.
Maxima - Maxima is a fairly complete computer algebra system written in Lisp with an emphasis on symbolic computation.
Xoctave - The Affordable Matlab alternative which makes you save money. Xoctave is a powerful software that is meant to unleash the power of GNU Octave by creating a complete scientific computing environment.
PTC Mathcad - PTC Mathcad PTC Mathcad is Engineering Math Software That Allows You to Perform, Analyze, and Share Your Most Vital Calculations.