These are some of the mathematical libraries
I use when I program in C. So far, we have the
following:
    2 Libraries for using Complex Numbers
        1 for complex in binary form
        1 for complex in polar form
    1 Library for using Distributions
    1 Library for using Graphs
    1 Library for using Matrices
    1 Library with extra functions for matrices
        that involve Vectors
    1 Library with some basic statistic
    1 Library for using Vectors
All of them are released under the Catware license
and the GPL license.

There's a README in each folder explaining what
functions havee been implemented, and in the code
there're some comments about what the function do.