r8col, a Fortran90 code which contains utility routines for R8COL's, that is, real MxN arrays, considered as N column vectors, each of length M. The data may be thought of as a matrix of multiple columns, and many operations will be carried out columnwise.
The information on this web page is distributed under the MIT license.
r8col is available in a C version and a C++ version and a Fortran90 version and a MATLAB version and an Octave version and a Python version.
linear_algebra, Fortran90 codes which carry out various linear algebra operations for matrices stored in a variety of formats.