dstsv - compute the solution to a system of linear equations A * X = B where A is a symmetric tridiagonal matrix
SUBROUTINE DSTSV( N, NRHS, L, D, SUBL, B, LDB, IPIV, INFO) INTEGER N, NRHS, LDB, INFO INTEGER IPIV(*) DOUBLE PRECISION L(*), D(*), SUBL(*), B(LDB,*)
SUBROUTINE DSTSV_64( N, NRHS, L, D, SUBL, B, LDB, IPIV, INFO) INTEGER*8 N, NRHS, LDB, INFO INTEGER*8 IPIV(*) DOUBLE PRECISION L(*), D(*), SUBL(*), B(LDB,*)
SUBROUTINE STSV( [N], [NRHS], L, D, SUBL, B, [LDB], IPIV, [INFO]) INTEGER :: N, NRHS, LDB, INFO INTEGER, DIMENSION(:) :: IPIV REAL(8), DIMENSION(:) :: L, D, SUBL REAL(8), DIMENSION(:,:) :: B
SUBROUTINE STSV_64( [N], [NRHS], L, D, SUBL, B, [LDB], IPIV, [INFO]) INTEGER(8) :: N, NRHS, LDB, INFO INTEGER(8), DIMENSION(:) :: IPIV REAL(8), DIMENSION(:) :: L, D, SUBL REAL(8), DIMENSION(:,:) :: B
#include <sunperf.h>
void dstsv(int n, int nrhs, double *l, double *d, double *subl, double *b, int ldb, int *ipiv, int *info);
void dstsv_64(long n, long nrhs, double *l, double *d, double *subl, double *b, long ldb, long *ipiv, long *info);
dstsv computes the solution to a system of linear equations A * X = B where A is a symmetric tridiagonal matrix.
INTEGER
The order of the matrix A. N > = 0.
REAL array, dimension (N)
On entry, the n-1 subdiagonal elements of the tridiagonal matrix A. On exit, part of the factorization of A.
REAL array, dimension (N)
On entry, the n diagonal elements of the tridiagonal matrix A. On exit, the n diagonal elements of the diagonal matrix D from the factorization of A.
REAL array, dimension (N)
On exit, part of the factorization of A.
INTEGER array, dimension (N)
On exit, the pivot indices of the factorization.
INTEGER
= 0: successful exit
< 0: if INFO = -i, the i-th argument had an illegal value
> 0: if INFO = i, D(k,k) is exactly zero. The factorization has been completed, but the block diagonal matrix D is exactly singular and division by zero will occur if it is used to solve a system of equations.