You know, I looked at PDL when I wrote this, and it was nearly impossible to use compared to Math::Matrix or Math::Matrix::Real. PDL has a "simq" method to deal with simultaneous equations, but I couldn't figure out from the docs how to use it. The PDL module Math::Matrix:Ops has about 5 lines describing simq......the interface is very obscure.

I also tried to use PDL to get the inverse of a matrix, which had no inverse, and was given results. Either I had the rows - columns setup wrong, or there is something wacky with PDL.