zspmv.f3
Usage
Functions/Subroutines
subroutine zspmv (uplo, n, alpha, ap, x, incx, beta, y, incy)
ZSPMV computes a matrix-vector product for complex vectors using a complex symmetric packed matrix
Function/Subroutine Documentation
subroutine zspmv (character uplo, integer n, complex*16 alpha, complex*16, dimension( * ) ap, complex*16, dimension( * ) x, integer incx, complex*16 beta, complex*16, dimension( * ) y, integer incy)
ZSPMV computes a matrix-vector product for complex vectors using a complex symmetric packed matrix
Purpose:
!> !> ZSPMV performs the matrix-vector operation !> !> y := alpha*A*x + beta*y, !> !> where alpha and beta are scalars, x and y are n element vectors and !> A is an n by n symmetric matrix, supplied in packed form. !>
Parameters
UPLO
!> UPLO is CHARACTER*1 !> On entry, UPLO specifies whether the upper or lower !> triangular part of the matrix A is supplied in the packed !> array AP as follows: !> !> UPLO = 'U' or 'u' The upper triangular part of A is !> supplied in AP. !> !> UPLO = 'L' or 'l' The lower triangular part of A is !> supplied in AP. !> !> Unchanged on exit. !>
N
!> N is INTEGER !> On entry, N specifies the order of the matrix A. !> N must be at least zero. !> Unchanged on exit. !>
ALPHA
!> ALPHA is COMPLEX*16 !> On entry, ALPHA specifies the scalar alpha. !> Unchanged on exit. !>
AP
!> AP is COMPLEX*16 array, dimension at least !> ( ( N*( N + 1 ) )/2 ). !> Before entry, with UPLO = 'U' or 'u', the array AP must !> contain the upper triangular part of the symmetric matrix !> packed sequentially, column by column, so that AP( 1 ) !> contains a( 1, 1 ), AP( 2 ) and AP( 3 ) contain a( 1, 2 ) !> and a( 2, 2 ) respectively, and so on. !> Before entry, with UPLO = 'L' or 'l', the array AP must !> contain the lower triangular part of the symmetric matrix !> packed sequentially, column by column, so that AP( 1 ) !> contains a( 1, 1 ), AP( 2 ) and AP( 3 ) contain a( 2, 1 ) !> and a( 3, 1 ) respectively, and so on. !> Unchanged on exit. !>
X
!> X is COMPLEX*16 array, dimension at least !> ( 1 + ( N - 1 )*abs( INCX ) ). !> Before entry, the incremented array X must contain the N- !> element vector x. !> Unchanged on exit. !>
INCX
!> INCX is INTEGER !> On entry, INCX specifies the increment for the elements of !> X. INCX must not be zero. !> Unchanged on exit. !>
BETA
!> BETA is COMPLEX*16 !> On entry, BETA specifies the scalar beta. When BETA is !> supplied as zero then Y need not be set on input. !> Unchanged on exit. !>
Y
!> Y is COMPLEX*16 array, dimension at least !> ( 1 + ( N - 1 )*abs( INCY ) ). !> Before entry, the incremented array Y must contain the n !> element vector y. On exit, Y is overwritten by the updated !> vector y. !>
INCY
!> INCY is INTEGER !> On entry, INCY specifies the increment for the elements of !> Y. INCY must not be zero. !> Unchanged on exit. !>
Author
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
NAG Ltd.
Definition at line 150 of file zspmv.f.
Releases
4 releases since Debian 7 (Wheezy); the text changed 3 times.