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dgemv.f(3)                          LAPACK                          dgemv.f(3)

NAME
       dgemv.f -

SYNOPSIS
   Functions/Subroutines
       subroutine dgemv (TRANS, M, N, ALPHA, A, LDA, X, INCX, BETA, Y, INCY)
           DGEMV

Function/Subroutine Documentation
   subroutine dgemv (characterTRANS, integerM, integerN, double
       precisionALPHA, double precision, dimension(lda,*)A, integerLDA, double
       precision, dimension(*)X, integerINCX, double precisionBETA, double
       precision, dimension(*)Y, integerINCY)
       DGEMV Purpose:

            DGEMV  performs one of the matrix-vector operations

               y := alpha*A*x + beta*y,   or   y := alpha*A**T*x + beta*y,

            where alpha and beta are scalars, x and y are vectors and A is an
            m by n matrix.

       Parameters:
           TRANS

                     TRANS is CHARACTER*1
                      On entry, TRANS specifies the operation to be performed as
                      follows:

                         TRANS = 'N' or 'n'   y := alpha*A*x + beta*y.

                         TRANS = 'T' or 't'   y := alpha*A**T*x + beta*y.

                         TRANS = 'C' or 'c'   y := alpha*A**T*x + beta*y.

           M

                     M is INTEGER
                      On entry, M specifies the number of rows of the matrix A.
                      M must be at least zero.

           N

                     N is INTEGER
                      On entry, N specifies the number of columns of the matrix A.
                      N must be at least zero.

           ALPHA

                     ALPHA is DOUBLE PRECISION.
                      On entry, ALPHA specifies the scalar alpha.

           A

                     A is DOUBLE PRECISION array of DIMENSION ( LDA, n ).
                      Before entry, the leading m by n part of the array A must
                      contain the matrix of coefficients.

           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, m ).

           X

                     X is DOUBLE PRECISION array of DIMENSION at least
                      ( 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.

           INCX

                     INCX is INTEGER
                      On entry, INCX specifies the increment for the elements of
                      X. INCX must not be zero.

           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.

           Y

                     Y is DOUBLE PRECISION array of DIMENSION at least
                      ( 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

                     INCY is INTEGER
                      On entry, INCY specifies the increment for the elements of
                      Y. INCY must not be zero.

       Author:
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Date:
           November 2011

       Further Details:

             Level 2 Blas routine.
             The vector and matrix arguments are not referenced when N = 0, or M = 0

             -- 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.

       Definition at line 157 of file dgemv.f.

Author
       Generated automatically by Doxygen for LAPACK from the source code.

Version 3.4.2                   Sat Nov 16 2013                     dgemv.f(3)