toms923, a Python code which evaluates the Pfaffian for a dense or banded skew symmetric matrix, by Michael Wimmer.
The computer code and data files made available on this web page are distributed under the MIT license
toms923 is available in a MATLAB version and a Python version.
test_mat, a Python code which defines test matrices for which the condition, determinant, eigenvalues, inverse, null vectors, P*L*U factorization or linear system solution are already known, including the Vandermonde and Wathen matrix.