Contents
stpsv - solve one of the systems of equations A*x = b, or
A'*x = b
SUBROUTINE STPSV(UPLO, TRANSA, DIAG, N, A, Y, INCY)
CHARACTER * 1 UPLO, TRANSA, DIAG
INTEGER N, INCY
REAL A(*), Y(*)
SUBROUTINE STPSV_64(UPLO, TRANSA, DIAG, N, A, Y, INCY)
CHARACTER * 1 UPLO, TRANSA, DIAG
INTEGER*8 N, INCY
REAL A(*), Y(*)
F95 INTERFACE
SUBROUTINE TPSV(UPLO, [TRANSA], DIAG, [N], A, Y, [INCY])
CHARACTER(LEN=1) :: UPLO, TRANSA, DIAG
INTEGER :: N, INCY
REAL, DIMENSION(:) :: A, Y
SUBROUTINE TPSV_64(UPLO, [TRANSA], DIAG, [N], A, Y, [INCY])
CHARACTER(LEN=1) :: UPLO, TRANSA, DIAG
INTEGER(8) :: N, INCY
REAL, DIMENSION(:) :: A, Y
C INTERFACE
#include <sunperf.h>
void stpsv(char uplo, char transa, char diag, int n, float
*a, float *y, int incy);
void stpsv_64(char uplo, char transa, char diag, long n,
float *a, float *y, long incy);
stpsv solves one of the systems of equations A*x = b, or
A'*x = b, where b and x are n element vectors and A is an n
by n unit, or non-unit, upper or lower triangular matrix,
supplied in packed form.
No test for singularity or near-singularity is included in
this routine. Such tests must be performed before calling
this routine.
UPLO (input)
On entry, UPLO specifies whether the matrix is an
upper or lower triangular matrix as follows:
UPLO = 'U' or 'u' A is an upper triangular
matrix.
UPLO = 'L' or 'l' A is a lower triangular
matrix.
Unchanged on exit.
TRANSA (input)
On entry, TRANSA specifies the equations to be
solved as follows:
TRANSA = 'N' or 'n' A*x = b.
TRANSA = 'T' or 't' A'*x = b.
TRANSA = 'C' or 'c' A'*x = b.
Unchanged on exit.
TRANSA is defaulted to 'N' for F95 INTERFACE.
DIAG (input)
On entry, DIAG specifies whether or not A is unit
triangular as follows:
DIAG = 'U' or 'u' A is assumed to be unit tri-
angular.
DIAG = 'N' or 'n' A is not assumed to be unit
triangular.
Unchanged on exit.
N (input)
On entry, N specifies the order of the matrix A.
N >= 0. Unchanged on exit.
A (input)
( ( n*( n + 1 ) )/2 ). Before entry with UPLO =
'U' or 'u', the array A must contain the upper
triangular matrix packed sequentially, column by
column, so that A( 1 ) contains a( 1, 1 ), A( 2 )
and A( 3 ) contain a( 1, 2 ) and a( 2, 2 ) respec-
tively, and so on. Before entry with UPLO = 'L'
or 'l', the array A must contain the lower tri-
angular matrix packed sequentially, column by
column, so that A( 1 ) contains a( 1, 1 ), A( 2 )
and A( 3 ) contain a( 2, 1 ) and a( 3, 1 ) respec-
tively, and so on. Note that when DIAG = 'U' or
'u', the diagonal elements of A are not refer-
enced, but are assumed to be unity. Unchanged on
exit.
Y (input/output)
( 1 + ( n - 1 )*abs( INCY ) ). Before entry, the
incremented array Y must contain the n element
right-hand side vector b. On exit, Y is overwrit-
ten with the solution vector x.
INCY (input)
On entry, INCY specifies the increment for the
elements of Y. INCY <> 0. Unchanged on exit.