#include "cs.h" /* solve U'x=b where x and b are dense. x=b on input, solution on output. */ int cs_utsolve (const cs *U, double *x) { int p, j, n, *Up, *Ui ; double *Ux ; if (!CS_CSC (U) || !x) return (0) ; /* check inputs */ n = U->n ; Up = U->p ; Ui = U->i ; Ux = U->x ; for (j = 0 ; j < n ; j++) { for (p = Up [j] ; p < Up [j+1]-1 ; p++) { x [j] -= Ux [p] * x [Ui [p]] ; } x [j] /= Ux [Up [j+1]-1] ; } return (1) ; }