ESMF_DLARF Subroutine

subroutine ESMF_DLARF(SIDE, M, N, V, INCV, TAU, C, LDC, WORK)

\brief \b ESMF_DLARF \htmlonly Download ESMF_DLARF + dependencies [TGZ] [ZIP] [TXT] \endhtmlonly \par Purpose:

\verbatim

ESMF_DLARF applies a real elementary reflector H to a real m by n matrix C, from either the left or the right. H is represented in the form

  H = I - tau * v * v**T

where tau is a real scalar and v is a real vector.

If tau = 0, then H is taken to be the unit matrix. \endverbatim \param[in] SIDE \verbatim SIDE is CHARACTER*1 = ‘L’: form H * C = ‘R’: form C * H \endverbatim

\param[in] M \verbatim M is INTEGER The number of rows of the matrix C. \endverbatim

\param[in] N \verbatim N is INTEGER The number of columns of the matrix C. \endverbatim

\param[in] V \verbatim V is DOUBLE PRECISION array, dimension (1 + (M-1)abs(INCV)) if SIDE = ‘L’ or (1 + (N-1)abs(INCV)) if SIDE = ‘R’ The vector v in the representation of H. V is not used if TAU = 0. \endverbatim

\param[in] INCV \verbatim INCV is INTEGER The increment between elements of v. INCV <> 0. \endverbatim

\param[in] TAU \verbatim TAU is DOUBLE PRECISION The value tau in the representation of H. \endverbatim

\param[in,out] C \verbatim C is DOUBLE PRECISION array, dimension (LDC,N) On entry, the m by n matrix C. On exit, C is overwritten by the matrix H * C if SIDE = ‘L’, or C * H if SIDE = ‘R’. \endverbatim

\param[in] LDC \verbatim LDC is INTEGER The leading dimension of the array C. LDC >= max(1,M). \endverbatim

\param[out] WORK \verbatim WORK is DOUBLE PRECISION array, dimension (N) if SIDE = ‘L’ or (M) if SIDE = ‘R’ \endverbatim \author Univ. of Tennessee \author Univ. of California Berkeley \author Univ. of Colorado Denver \author NAG Ltd. \date November 2011 \ingroup doubleOTHERauxiliary

Arguments

Type IntentOptional Attributes Name
character(len=1) :: SIDE
integer :: M
integer :: N
double precision :: V(*)
integer :: INCV
double precision :: TAU
double precision :: C(LDC,*)
integer :: LDC
double precision :: WORK(*)