I'm looking for the C# implementation of Projected Gauss-Seidel algorithm for solving the linear complementarity problem. So far I've found the one written in C++ in the Bullet library, but unfortunately it's highly optimized (so it would be hard to translate it into C#).
In the similar question one proposed to take a look of the numerical libraries for .NET. All of them contain only algorithms for solving systems of linear equations.
Edit: Even as I've found one, it doesn't appear to be complete, so the question is still open.