gstrs(3P) Sun Performance Library gstrs(3P)NAME
gstrs: cgstrs, dgstrs, sgstrs, zgstrs - solves a system of linear equa‐
tions A*X=B or A'*X=B with A sparse and B dense, using the LU factor‐
ization computed by sgstrf.
SYNOPSIS
#include <sunperf.h>
void sgstrs(trans_t trans, SuperMatrix *L, SuperMatrix *U, int *perm_c,
int *perm_r, SuperMatrix *B, SuperLUStat_t *stat, int *info))
void dgstrs(trans_t trans, SuperMatrix *L, SuperMatrix *U, int *perm_c,
int *perm_r, SuperMatrix *B, SuperLUStat_t *stat, int *info))
void cgstrs(trans_t trans, SuperMatrix *L, SuperMatrix *U, int *perm_c,
int *perm_r, SuperMatrix *B, SuperLUStat_t *stat, int *info))
void zgstrs(trans_t trans, SuperMatrix *L, SuperMatrix *U, int *perm_c,
int *perm_r, SuperMatrix *B, SuperLUStat_t *stat, int *info))
void sgstrs_64(trans_t trans, SuperMatrix_64 *L, SuperMatrix_64 *U,
long *perm_c, long *perm_r, SuperMatrix_64 *B, SuperLUStat_t_64
*stat, long *info))
void dgstrs_64(trans_t trans, SuperMatrix_64 *L, SuperMatrix_64 *U,
long *perm_c, long *perm_r, SuperMatrix_64 *B, SuperLUStat_t_64
*stat, long *info))
void cgstrs_64(trans_t trans, SuperMatrix_64 *L, SuperMatrix_64 *U,
long *perm_c, long *perm_r, SuperMatrix_64 *B, SuperLUStat_t_64
*stat, long *info))
void zgstrs_64(trans_t trans, SuperMatrix_64 *L, SuperMatrix_64 *U,
long *perm_c, long *perm_r, SuperMatrix_64 *B, SuperLUStat_t_64
*stat, long *info))
PURPOSEgstrs is a SuperLU routine that solves a system of linear equations
A*X=B or A'*X=B with A sparse and B dense, using the LU factorization
computed by sgstrf.
ARGUMENTS
trans_t trans (input)
Specifies the form of the system of equations:
= NOTRANS: A * X = B (No transpose)
= TRANS: A'* X = B (Transpose)
= CONJ: A**H * X = B (Conjugate transpose)
SuperMatrix *A (input)
Original matrix A in the system, or the scaled A if equilibra‐
tion was done. The type of A can be:
Stype = SLU_NC; Dtype = SLU_S; Mtype = SLU_GE.
SuperMatrix *L (input)
The factor L from the factorization Pr*A=L*U. It uses com‐
pressed row subscripts storage for supernodes, i.e., L has
types: Stype = SLU_SC, Dtype = SLU_S, Mtype = SLU_TRLU
SuperMatrix *U (input)
The factor U from the factorization Pr*A*Pc=L*U. It uses col‐
umn-wise storage scheme, i.e., U has types: Stype = SLU_NC,
Dtype = SLU_S, Mtype = SLU_TRU.
int *perm_c (input)
Column permutation vector of size (A->ncol) which defines the
permutation matrix Pc. perm_c[i] = j means column i of A is in
position j in A*Pc.
int *perm_r (input)
Row permutation vector of size (A->nrow) which defines the per‐
mutation matrix Pr. perm_r[i] = j means row i of A is in posi‐
tion j in Pr*A.
SuperMatrix *B (input/output)
On entry, the right hand side matrix B.
On exit, the solution matrix if info = 0.
B has types: Stype = SLU_DN, Dtype = SLU_S, Mtype = SLU_GE.
SuperLUStat_t *stat (output)
Records the statistics on runtime and floating-point operation
count.
int *info (output)
= 0:
successful exit
< 0: if info = -i, the i-th argument had an illegal value
COPYRIGHT
Copyright (c) 2003, The Regents of the University of California,
through Lawrence Berkeley National Laboratory (subject to receipt of
any required approvals from U.S. Dept. of Energy)
SEE ALSO
SuperMatrix
set_default_options
StatInit
StatFree
gstrf
http://crd.lbl.gov/~xiaoye/SuperLU/
James W. Demmel, Stanley C. Eisenstat, John R. Gilbert, Xiaoye S. Li
and Joseph W. H. Liu, "A supernodal approach to sparse partial pivot‐
ing", SIAM J. Matrix Analysis and Applications, Vol. 20, Num. 3, 1999,
pp. 720-755.
6 Mar 2009 gstrs(3P)