Polynomial preconditioned GMRES-DR

GMRES-DR (Gneralized Minimal Residual algorithm with Deflated Restarting), developed by Dr. Ronald Morgan in 2002, is a well known algorithm in QCD matrix calculation. We did a modified vertion of regular GMRES-DR by combing it with the polynomial conditioning method, which can help improve the eigenvalue spectrum of the lattice QCD matrix, especially for ill-conditioned matrix with small eigenvalues.