GSL is closer to something like BLAS or LAPACK[1] -- it's a library that provides tested/reliable/optimized implementations of commonly used functions in scient

GSL is closer to something like BLAS or LAPACK[1] -- it's a library that provides tested/reliable/optimized implementations of commonly used functions in scientific computing. The other software you listed is more user facing--and commonly provides wrappers around libraries like GSL. For instance, MATLAB relies heavily on BLAS & LAPACK, as does numpy; I'm less familiar with whether GSL is called from any well known packages other than Octave, but there are definitely bindings for Python (and maybe R? I don't write any R though) [1] Respectively, "Basic Linear Algebra Subsystem" and "Linear Algebra PACKage"