Rlab
Rlab is an interactive, interpreted scientific programming environment written by Ian Searle. Rlab is a very high level language intended to provide fast prototyping and program development, as well as easy data-visualization, and processing. Rlab is not a clone of languages such as those used by tools like MATLAB or Matrix-X/Xmath. However, as Rlab focuses on creating a good experimental environment (or laboratory) in which to do matrix math, it can be called MATLAB-like since the programming language possesses similar operators and concepts.Rlab does not try to be a MATLAB clone. Instead, it borrows the best features of the MATLAB language and provides improved language syntax and semantics. The syntax has been improved to allow users more expression and reduce ambiguities. The variable scoping rules have been improved to facilitate creation of larger programs and program libraries. A heterogeneous associative array has been added to allow users to create and operate on arbitrary data structures. The fundamental data type is a floating point matrix (either real or complex), though RLaB also includes string matrices, and sparse numerical matrices (both real and complex).
Rlab is no longer under active development. Binary versions are available for Linux and for Windows, and source code is available under the GPL.