stpmv
stpmv - perform one of the matrix-vector operations x := A*x, or x := A'*x
SUBROUTINE STPMV( UPLO, TRANSA, DIAG, N, A, Y, INCY)
CHARACTER * 1 UPLO, TRANSA, DIAG
INTEGER N, INCY
REAL A(*), Y(*)
SUBROUTINE STPMV_64( UPLO, TRANSA, DIAG, N, A, Y, INCY)
CHARACTER * 1 UPLO, TRANSA, DIAG
INTEGER*8 N, INCY
REAL A(*), Y(*)
SUBROUTINE TPMV( UPLO, [TRANSA], DIAG, [N], A, Y, [INCY])
CHARACTER(LEN=1) :: UPLO, TRANSA, DIAG
INTEGER :: N, INCY
REAL, DIMENSION(:) :: A, Y
SUBROUTINE TPMV_64( UPLO, [TRANSA], DIAG, [N], A, Y, [INCY])
CHARACTER(LEN=1) :: UPLO, TRANSA, DIAG
INTEGER(8) :: N, INCY
REAL, DIMENSION(:) :: A, Y
#include <sunperf.h>
void stpmv(char uplo, char transa, char diag, int n, float *a, float *y, int incy);
void stpmv_64(char uplo, char transa, char diag, long n, float *a, float *y, long incy);
stpmv performs one of the matrix-vector operations
x := A*x, or x := A'*x,
where x is an n element vector and A is an n by n unit, or non-unit,
upper or lower triangular matrix, supplied in packed form.
-
* 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 operation to be performed as
follows:
TRANSA = 'N' or 'n' x := A*x.
TRANSA = 'T' or 't' x := A'*x.
TRANSA = 'C' or 'c' x := A'*x.
Unchanged on exit.
-
* 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 triangular.
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 )
respectively, and so on.
Before entry with UPLO = 'L' or 'l', the array A must
contain the lower triangular 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 )
respectively, and so on.
Note that when DIAG = 'U' or 'u', the diagonal elements of
A are not referenced, 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 vector x. On exit, Y is overwritten with the
tranformed vector x.
-
* INCY (input)
-
On entry, INCY specifies the increment for the elements of
Y. INCY <> 0.
Unchanged on exit.