!>
!> DLA_SYAMV  performs the matrix-vector operation
!>
!>         y := alpha*abs(A)*abs(x) + beta*abs(y),
!>
!> where alpha and beta are scalars, x and y are vectors and A is an
!> n by n symmetric matrix.
!>
!> This function is primarily used in calculating error bounds.
!> To protect against underflow during evaluation, components in
!> the resulting vector are perturbed away from zero by (N+1)
!> times the underflow threshold.  To prevent unnecessarily large
!> errors for block-structure embedded in general matrices,
!>  zero components are not perturbed.  A zero
!> entry is considered  if all multiplications involved
!> in computing that entry have at least one zero multiplicand.
!> 

UPLO

!>          UPLO is INTEGER
!>           On entry, UPLO specifies whether the upper or lower
!>           triangular part of the array A is to be referenced as
!>           follows:
!>
!>              UPLO = BLAS_UPPER   Only the upper triangular part of A
!>                                  is to be referenced.
!>
!>              UPLO = BLAS_LOWER   Only the lower triangular part of A
!>                                  is to be referenced.
!>
!>           Unchanged on exit.
!> 

N

!>          N is INTEGER
!>           On entry, N specifies the number of columns of the matrix A.
!>           N must be at least zero.
!>           Unchanged on exit.
!> 

ALPHA

!>          ALPHA is DOUBLE PRECISION .
!>           On entry, ALPHA specifies the scalar alpha.
!>           Unchanged on exit.
!> 

A

!>          A is DOUBLE PRECISION array, dimension ( LDA, n ).
!>           Before entry, the leading m by n part of the array A must
!>           contain the matrix of coefficients.
!>           Unchanged on exit.
!> 

LDA

!>          LDA is 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

!>          X is DOUBLE PRECISION array, dimension
!>           ( 1 + ( n - 1 )*abs( INCX ) )
!>           Before entry, the incremented array X must contain the
!>           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 DOUBLE PRECISION .
!>           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 DOUBLE PRECISION array, dimension
!>           ( 1 + ( n - 1 )*abs( INCY ) )
!>           Before entry with BETA non-zero, the incremented array Y
!>           must contain the 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.
!> 

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!>
!>  Level 2 Blas routine.
!>
!>  -- Written on 22-October-1986.
!>     Jack Dongarra, Argonne National Lab.
!>     Jeremy Du Croz, Nag Central Office.
!>     Sven Hammarling, Nag Central Office.
!>     Richard Hanson, Sandia National Labs.
!>  -- Modified for the absolute-value product, April 2006
!>     Jason Riedy, UC Berkeley
!>