MATLAB is a widely used commercial, numerical computing environemnt and fourth-generation programming language. It has a large number of built in and third party tools useful for a wide range of subjects and about a million users world wide. The langaue is highly vectorized and easy to learn. For numerical computation, MATLAB gives better (and sometime much better) performences relative to IDL, Python and f77 (f77 without using LINPACK or other similar libraries).
MATLAB - tools for astronomy:
Astronomy & Astrophysics package for MATLAB - includes over 500 MATLAB functions, and several data files and astronomical catalogs, which are organized in several toolboxes and several data/catalogs directories. The scripts covers a wide range of subjects including:
astronomical image processing, astronomical spectra, catalog retrieval and searches, celestial maps and projections, cosmology, ds9 control, ephemerides, time and coordinates manipulation, function fitting, general utilities, geometry, gravitational lensing, plotting, statistics, time series analysis.