zspmv.f man page

zspmv.f —

Synopsis

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 (characterUPLO, integerN, complex*16ALPHA, complex*16, dimension( * )AP, complex*16, dimension( * )X, integerINCX, complex*16BETA, complex*16, dimension( * )Y, integerINCY)

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.

Date:

September 2012

Definition at line 152 of file zspmv.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

zspmv(3) is an alias of zspmv.f(3).

Sat Nov 16 2013 Version 3.4.2 LAPACK