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NAME CSYMV - perform the matrix-vector operation y := alpha*A*x + beta*y, SYNOPSIS SUBROUTINE CSYMV( UPLO, N, ALPHA, A, LDA, X, INCX, BETA, Y, INCY ) CHARACTER UPLO INTEGER INCX, INCY, LDA, N COMPLEX ALPHA, BETA COMPLEX A( LDA, * ), X( * ), Y( * ) PURPOSE CSYMV performs the matrix-vector operation where alpha and beta are scalars, x and y are n element vec- tors and A is an n by n symmetric matrix. ARGUMENTS UPLO - CHARACTER*1 On entry, UPLO specifies whether the upper or lower triangular part of the array A is to be referenced as follows: UPLO = 'U' or 'u' Only the upper triangular part of A is to be referenced. UPLO = 'L' or 'l' Only the lower triangular part of A is to be referenced. Unchanged on exit. N - INTEGER On entry, N specifies the order of the matrix A. N must be at least zero. Unchanged on exit. ALPHA - COMPLEX On entry, ALPHA specifies the scalar alpha. Unchanged on exit. A - COMPLEX array, dimension( LDA, N ) Before entry with UPLO = 'U' or 'u', the leading n by n upper triangular part of the array A must con- tain the upper triangular part of the symmetric matrix and the strictly lower triangular part of A is not referenced. Before entry with UPLO = 'L' or 'l', the leading n by n lower triangular part of the array A must contain the lower triangular part of the sym- metric matrix and the strictly upper triangular part of A is not referenced. Unchanged on exit. LDA - INTEGER On entry, LDA specifies the first dimension of A as declared in the calling (sub) program. LDA must be at least max( 1, N ). Unchanged on exit. X - COMPLEX array, dimension at least ( 1 + ( N - 1 )*abs( INCX ) ). Before entry, the incremented array X must contain the N- element vec- tor x. Unchanged on exit. INCX - INTEGER On entry, INCX specifies the increment for the ele- ments of X. INCX must not be zero. Unchanged on exit. BETA - 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 - 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 - INTEGER On entry, INCY specifies the increment for the ele- ments of Y. INCY must not be zero. Unchanged on exit.