The GNU Scientific Library (GSL) is a collection of routines for numerical computing. The routines have been written in C and present an Applications Programming Interface (API) for C programmers, allowing wrappers to be written for very high level languages. Where possible the routines have been based on reliable public-domain packages such as FFTPACK and QUADPACK, which the developers of GSL have re-implemented in C with modern coding conventions.
In order to use GSL routines in a C-based program, it is only necessary to add the appropriate compile and link option.
gcc gsl.c -lgsl -L/usr/lib64/libgsl.so -lgslcblas -L/usr/lib64/libgslcblas.so