ztpmv


NAME

ztpmv - perform one of the matrix-vector operations x := A*x, or x := A'*x, or x := conjg( A' )*x


SYNOPSIS

  SUBROUTINE ZTPMV( UPLO, TRANSA, DIAG, N, A, Y, INCY)
  CHARACTER * 1 UPLO, TRANSA, DIAG
  DOUBLE COMPLEX A(*), Y(*)
  INTEGER N, INCY
 
  SUBROUTINE ZTPMV_64( UPLO, TRANSA, DIAG, N, A, Y, INCY)
  CHARACTER * 1 UPLO, TRANSA, DIAG
  DOUBLE COMPLEX A(*), Y(*)
  INTEGER*8 N, INCY
 

F95 INTERFACE

  SUBROUTINE TPMV( UPLO, [TRANSA], DIAG, [N], A, Y, [INCY])
  CHARACTER(LEN=1) :: UPLO, TRANSA, DIAG
  COMPLEX(8), DIMENSION(:) :: A, Y
  INTEGER :: N, INCY
 
  SUBROUTINE TPMV_64( UPLO, [TRANSA], DIAG, [N], A, Y, [INCY])
  CHARACTER(LEN=1) :: UPLO, TRANSA, DIAG
  COMPLEX(8), DIMENSION(:) :: A, Y
  INTEGER(8) :: N, INCY
 

C INTERFACE

#include <sunperf.h>

void ztpmv(char uplo, char transa, char diag, int n, doublecomplex *a, doublecomplex *y, int incy);

void ztpmv_64(char uplo, char transa, char diag, long n, doublecomplex *a, doublecomplex *y, long incy);


PURPOSE

ztpmv performs one of the matrix-vector operations x := A*x, or x := A'*x, or x := conjg( 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.


ARGUMENTS

* 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 := conjg( 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.