KmlDssSymSolve?I

Solve LDL^Tx=b.

Interface Definition

C interface:

int KmlDssSymSolveSI(KmlSolverTask **pHandle, int nb, float *x, int ldx, float *b, int ldb);

int KmlDssSymSolveDI(KmlSolverTask **pHandle, int nb, double *x, int ldx, double *b, int ldb);

int KmlDssSymSolveCI(KmlSolverTask **pHandle, int nb, kml_complex_float *x, int ldx, kml_complex_float *b, int ldb);

int KmlDssSymSolveZI(KmlSolverTask **pHandle, int nb, kml_complex_double *x, int ldx, kml_complex_double *b, int ldb);

Parameters

Parameter	Type	Description	Input/Output
pHandle	KmlSolverTask **	Solver handle, which is a variable passed from a previous step.	Input
nb	int	Number of RHS vectors.	Input
x	float * in KmlDssSymSolveSI double * in KmlDssSymSolveDI kml_complex_float * in KmlDssSymSolveCI kml_complex_double * in KmlDssSymSolveZI	Dense vector that stores the solution result. The number of elements is ldxnb. The i-th element of the k-th vector is stored at x[i + k ldx]**.	Output
ldx	int	Leading dimension of x. ldx ≥ max(1, n).	Input
b	float * in KmlDssSymSolveSI double * in KmlDssSymSolveDI kml_complex_float * in KmlDssSymSolveCI kml_complex_double * in KmlDssSymSolveZI	Dense vector that stores the RHS. The quantity of elements is ldbnb. The i-th element of the k-th vector is stored at b[i + k ldb]**.	Input
ldb	int	Leading dimension of b. ldb ≥ max(1, n).	Input

Return Value

Return Value	Type	Description
KMLSS_NO_ERROR	int	The execution is successful.
KMLSS_NULL_ARGUMENT	int	A null parameter exists in {pHandle, x, b}.
KMLSS_BAD_NB	int	The value of nb is less than or equal to 0.
KMLSS_BAD_HANDLE	int	The format of pHandle is incorrect.
KMLSS_BAD_LDX	int	The value of ldx is out of the valid range.
KMLSS_BAD_LDB	int	The value of ldb is out of the valid range.
KMLSS_INVALID_CALL_ORDER	int	Incorrect function execution sequence: The solution function is executed without prior factorization.
KMLSS_NO_MEMORY	int	Memory allocation failed.

Dependencies

#include "kml_dss.h" or #include "kml_solver.h"

Examples

C interface:

int n = 8;
int ia[9] = {0, 2, 4, 6, 7, 8, 9, 10, 11};
int ja[11] = {0, 7, 1, 6, 2, 5, 3, 4, 5, 6, 7};
double a[11] = {1.0, 2.0, -2.0, 3.0, 3.0, 4.0, -4.0, 5.0, -6.0, 7.0, 8.0};

double b[8] = {3.0, 1.0, 7.0, -4.0, 5.0, -2.0, 10.0, 10.0};
double x[8];
int nrhs = 1;
int ldx = n, ldb = n;

KmlSolverTask *handle;
int ierr = KmlDssSymInitDI(&handle, n, a, ja, ia);
if (ierr != 0) {
        printf("\nERROR in KmlDssSymInitDI: %d", ierr);
}
ierr = KmlDssSymAnalyzeDI(&handle);
if (ierr != 0) {
        printf("\nERROR in KmlDssSymAnalyzeDI: %d", ierr);
}
ierr = KmlDssSymFactorizeDI(&handle);
if (ierr != 0) {
        printf("\nERROR in KmlDssSymFactorizeDI: %d", ierr);
}
ierr = KmlDssSymSolveDI(&handle, nrhs, x, ldx, b, ldb);
if (ierr != 0) {
        printf("\nERROR in KmlDssSymSolveDI: %d", ierr);
}
for (int i = 0; i < n; i++) {
        printf("%lf ", x[i]);
}
printf("\n");

Output:

1.000000 1.000000 1.000000 1.000000 1.000000 1.000000 1.000000 1.000000

Parent topic: LDLT (DEPRECATED)