dstsv(3P) Sun Performance Library dstsv(3P)NAMEdstsv - compute the solution to a system of linear equations A * X = B
where A is a symmetric tridiagonal matrix
SYNOPSIS
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,*)
F95 INTERFACE
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
C INTERFACE
#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);
PURPOSEdstsv computes the solution to a system of linear equations A * X = B
where A is a symmetric tridiagonal matrix.
ARGUMENTS
N (input)
INTEGER
The order of the matrix A. N >= 0.
NRHS (input)
The number of right hand sides in B.
L (input/output)
REAL array, dimension (N-1)
On entry, the n-1 subdiagonal elements of the tridiagonal
matrix A. On exit, part of the factorization of A.
D (input/output)
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.
SUBL (output)
REAL array, dimension (N-2)
On exit, part of the factorization of A.
B (input/output)
The columns of B contain the right hand sides.
LDB (input)
The leading dimension of B as specified in a type or DIMEN‐
SION statement.
IPIV (output)
INTEGER array, dimension (N)
On exit, the pivot indices of the factorization.
INFO (output)
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.
6 Mar 2009 dstsv(3P)
