Contents
dsptrs - solve a system of linear equations A*X = B with a
real symmetric matrix A stored in packed format using the
factorization A = U*D*U**T or A = L*D*L**T computed by
DSPTRF
SUBROUTINE DSPTRS(UPLO, N, NRHS, AP, IPIVOT, B, LDB, INFO)
CHARACTER * 1 UPLO
INTEGER N, NRHS, LDB, INFO
INTEGER IPIVOT(*)
DOUBLE PRECISION AP(*), B(LDB,*)
SUBROUTINE DSPTRS_64(UPLO, N, NRHS, AP, IPIVOT, B, LDB, INFO)
CHARACTER * 1 UPLO
INTEGER*8 N, NRHS, LDB, INFO
INTEGER*8 IPIVOT(*)
DOUBLE PRECISION AP(*), B(LDB,*)
F95 INTERFACE
SUBROUTINE SPTRS(UPLO, [N], [NRHS], AP, IPIVOT, B, [LDB], [INFO])
CHARACTER(LEN=1) :: UPLO
INTEGER :: N, NRHS, LDB, INFO
INTEGER, DIMENSION(:) :: IPIVOT
REAL(8), DIMENSION(:) :: AP
REAL(8), DIMENSION(:,:) :: B
SUBROUTINE SPTRS_64(UPLO, [N], [NRHS], AP, IPIVOT, B, [LDB], [INFO])
CHARACTER(LEN=1) :: UPLO
INTEGER(8) :: N, NRHS, LDB, INFO
INTEGER(8), DIMENSION(:) :: IPIVOT
REAL(8), DIMENSION(:) :: AP
REAL(8), DIMENSION(:,:) :: B
C INTERFACE
#include <sunperf.h>
void dsptrs(char uplo, int n, int nrhs, double *ap, int
*ipivot, double *b, int ldb, int *info);
void dsptrs_64(char uplo, long n, long nrhs, double *ap,
long *ipivot, double *b, long ldb, long *info);
dsptrs solves a system of linear equations A*X = B with a
real symmetric matrix A stored in packed format using the
factorization A = U*D*U**T or A = L*D*L**T computed by
DSPTRF.
UPLO (input)
Specifies whether the details of the factorization
are stored as an upper or lower triangular matrix.
= 'U': Upper triangular, form is A = U*D*U**T;
= 'L': Lower triangular, form is A = L*D*L**T.
N (input) The order of the matrix A. N >= 0.
NRHS (input)
The number of right hand sides, i.e., the number
of columns of the matrix B. NRHS >= 0.
AP (input)
Double precision array, dimension (N*(N+1)/2) The
block diagonal matrix D and the multipliers used
to obtain the factor U or L as computed by DSPTRF,
stored as a packed triangular matrix.
IPIVOT (input)
Integer array, dimension (N) Details of the inter-
changes and the block structure of D as determined
by DSPTRF.
B (input/output)
Double precision array, dimension (LDB,NRHS) On
entry, the right hand side matrix B. On exit, the
solution matrix X.
LDB (input)
The leading dimension of the array B. LDB >=
max(1,N).
INFO (output)
= 0: successful exit
< 0: if INFO = -i, the i-th argument had an ille-
gal value