algebra\arnoldi.m .......\cholesky.m .......\gauseidel.m .......\gmres.m .......\gsqr.m .......\hessenberg.m .......\householder.m .......\huidai.m .......\jacobi.m .......\lufenjie.m .......\PLUdecomposition.m .......\powerite.m .......\ray.m algebra