GNU Octave is a free open source software (FOSS) package which is "mostly compatible" with MATLAB. It provides a very similar command line interpreter interface, and implements most of the functionality in the commercial MATLAB product. Nevertheless, there are subtle differences which anyone attempting to switch to GNU Octave or to write MATLAB/GNU Octave-compatible scripts must appreciate.

Octave was conceived in 1988 and has been under development since 1992. Over the years a great deal of progress has been made, especially in the area of graphics and plotting. The code base is currently maintained by John W. Eaton and is named after Octave Levenspiel, a former professor of Eaton's.

Most exercises in this workshop should work in Octave without changes, or with trivial changes, but this has not been tested. What definitely won't work are the exercises interacting with other languages, as Octave takes a different approach than that of MATLAB. Additionally, it is worth pointing out that one area where Octave is lagging behind MATLAB at the moment is in its ability to do parallel computing. However, some facilities do exist, such as the MPI Toolbox for Octave (MPITB) and the Parallel package.