CSPMV(3)
performs the matrixvector operation y := alpha*A*x + beta*y,
SYNOPSIS
 SUBROUTINE CSPMV(

UPLO, N, ALPHA, AP, X, INCX, BETA, Y, INCY )

CHARACTER
UPLO

INTEGER
INCX, INCY, N

COMPLEX
ALPHA, BETA

COMPLEX
AP( * ), X( * ), Y( * )
PURPOSE
CSPMV performs the matrixvector operation
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.
ARGUMENTS
 UPLO (input) 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 (input) INTEGER

On entry, N specifies the order of the matrix A.
N must be at least zero.
Unchanged on exit.
 ALPHA (input) COMPLEX

On entry, ALPHA specifies the scalar alpha.
Unchanged on exit.
 AP (input) COMPLEX 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 (input) COMPLEX 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 (input) INTEGER

On entry, INCX specifies the increment for the elements of
X. INCX must not be zero.
Unchanged on exit.
 BETA (input) COMPLEX

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 (input/output) COMPLEX 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 (input) INTEGER

On entry, INCY specifies the increment for the elements of
Y. INCY must not be zero.
Unchanged on exit.