GNU Octave

Website: gnu.org/software/octave/

GNU Octave is a high-level programming language primarily intended for scientific computing and numerical computation.

Octave helps in solving linear and nonlinear problems numerically, and for performing other numerical experiments using a language that is mostly compatible with MATLAB.

It may also be used as a batch-oriented language.

As part of the GNU Project, it is free software under the terms of the GNU General Public License.