/* * CXSPARSE: a Concise Sparse Matrix package - Extended. * Copyright (c) 2006-2009, Timothy A. Davis. * http://www.cise.ufl.edu/research/sparse/CXSparse * * CXSparse is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * CXSparse is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this Module; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ #include "cs.h" /* solve Lx=b where x and b are dense. x=b on input, solution on output. */ CS_INT cs_lsolve (const cs *L, CS_ENTRY *x) { CS_INT p, j, n, *Lp, *Li ; CS_ENTRY *Lx ; if (!CS_CSC (L) || !x) return (0) ; /* check inputs */ n = L->n ; Lp = L->p ; Li = L->i ; Lx = L->x ; for (j = 0 ; j < n ; j++) { x [j] /= Lx [Lp [j]] ; for (p = Lp [j]+1 ; p < Lp [j+1] ; p++) { x [Li [p]] -= Lx [p] * x [j] ; } } return (1) ; }