Provided by: liblapack-doc_3.3.1-1_all bug

NAME

       LAPACK-3  -  performs  one  of  the  matrix-vector operations   y := alpha*abs(A)*abs(x) +
       beta*abs(y),

SYNOPSIS

       SUBROUTINE CLA_GEAMV ( TRANS, M, N, ALPHA, A, LDA, X, INCX, BETA, Y, INCY )

           IMPLICIT         NONE

           REAL             ALPHA, BETA

           INTEGER          INCX, INCY, LDA, M, N

           INTEGER          TRANS

           COMPLEX          A( LDA, * ), X( * )

           REAL             Y( * )

PURPOSE

       CLA_GEAMV  performs one of the matrix-vector operations
           or   y := alpha*abs(A)**T*abs(x) + beta*abs(y),
        where alpha and beta are scalars, x and y are vectors and A is an
        m by n 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,
        "symbolically" zero components are not perturbed.  A zero
        entry is considered "symbolic" if all multiplications involved
        in computing that entry have at least one zero multiplicand.

ARGUMENTS

        TRANS   (input) INTEGER
                On entry, TRANS specifies the operation to be performed as
                follows:

        BLAS_NO_TRANS      y := alpha*abs(A)*abs(x) + beta*abs(y)
                           BLAS_TRANS         y := alpha*abs(A**T)*abs(x) + beta*abs(y)
                           BLAS_CONJ_TRANS    y := alpha*abs(A**T)*abs(x) + beta*abs(y)
                           Unchanged on exit.

        M        (input) INTEGER
                 On entry, M specifies the number of rows of the matrix A.
                 M must be at least zero.
                 Unchanged on exit.

        N        (input) INTEGER
                 On entry, N specifies the number of columns of the matrix A.
                 N must be at least zero.
                 Unchanged on exit.

        ALPHA    (input) REAL
                 On entry, ALPHA specifies the scalar alpha.
                 Unchanged on exit.

        A        (input) COMPLEX 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      (input) INTEGER
                 On entry, LDA specifies the first dimension of A as declared
                 in the calling (sub) program. LDA must be at least
                 max( 1, m ).
                 Unchanged on exit.

        X        (input) COMPLEX array, dimension
                 ( 1 + ( n - 1 )*abs( INCX ) ) when TRANS = 'N' or 'n'
                 and at least
                 ( 1 + ( m - 1 )*abs( INCX ) ) otherwise.
                 Before entry, the incremented array X must contain the
                 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) REAL
                 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) REAL array, dimension
                 ( 1 + ( m - 1 )*abs( INCY ) ) when TRANS = 'N' or 'n'
                 and at least
                 ( 1 + ( n - 1 )*abs( INCY ) ) otherwise.
                 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     (input) INTEGER
                 On entry, INCY specifies the increment for the elements of
                 Y. INCY must not be zero.
                 Unchanged on exit.
                 Level 2 Blas routine.

    LAPACK routine (version 3.3.1)          April 2011                         CLA_GEAMV(3lapack)