KmlIssGcrSolve?I

Solve a system of linear equations.

Interface Definition

C interface:

int KmlIssGcrSolveSI(KmlSolverTask **handle, int nb, float *x, int ldx, const float *b, int ldb);

int KmlIssGcrSolveDI(KmlSolverTask **handle, int nb, double *x, int ldx, const double *b, int ldb);

Parameters

Parameter	Type	Description	Input/Output
handle	KmlSolverTask **	Solver handle, which transfers a variable defined previously.	Input/Output
nb	int	Number of RHS vectors. The value of nb can only be 1.	Input
x	float * in KmlIssGcrSolveSI double * in KmlIssGcrSolveDI	Array that reads and stores the solution result, with n elements.	Input/Output
ldx	int	Size of the leading dimension of x. This is a reserved parameter.	Input
b	float * in KmlIssGcrSolveSI double * in KmlIssGcrSolveDI	Array that reads the RHS terms, with n elements.	Input
ldb	int	Size of the leading dimension of b. This is a reserved parameter.	Input

Return Values

Return Value	Type	Description
KMLSS_NO_ERROR	int	The execution is successful.
KMLSS_BAD_NB	int	The value of nb is not 1.
KML_NO_MEMORY	int	The memory is insufficient.
KMLSS_NULL_ARGUMENT	int	A null argument exists in {handle, x, b}.

Dependency

#include "kml_iss.h"

Example

C interface:

KmlSolverTask *handle;
int ierr;
int n = 8;  

double a[26] = {1.0, 1.0, 2.0, 9.0, 2.0, 1.0, -3.0, 2.0, 3.0, 2.0, 1.0, 1.0, 9.0, -5.0, 2.0, 6.0, 1.0, -3.0, 1.0, 4.0, 1.0, -5.0, 7.0, 2.0,1.0, 2.0};
int ja[26] = {0, 3, 4, 1, 2, 3, 5, 1, 2, 7, 0, 1, 3, 6, 0, 4, 5, 1, 4, 5, 7, 3, 6, 2, 5, 7};
int ia[9] = {0, 3, 7, 10, 14, 17, 21, 23, 26};

ierr = KmlIssGcrInitDI(&handle, n, a, ja, ia);
ierr = KmlIssGcrAnalyzeDI(&handle);
ierr = KmlIssGcrFactorizeDI(&handle);

int nd = 1;
int idata[] = {0};
double ddata[] = {0};
double eps = 1e-4;
ierr = KmlIssGcrSetDID(&handle, KMLSS_THRESHOLD, &eps, nd);
int max_iters = 2000;
ierr = KmlIssGcrSetDII(&handle, KMLSS_MAX_ITERATION_COUNT, &max_iters, nd);

int ldx = n;
int ldb = n; 
int nb = 1;
double b[8] = {4.0, 9.0, 7.0, 6.0, 9.0, 3.0, 2.0, 5.0};
double x[8];
ierr = KmlIssGcrSolveDI(&handle, nb, x, ldx, b, ldb);
if (ierr != 0) {
    printf("\nERROR in KmlIssGcrSolveDI: %d", ierr);
    return 1;
    }

Parent topic: GCR