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SUBROUTINE ZLARSCL2 ( M, N, D, X, LDX )
*
* -- LAPACK routine (version 3.2) --
* -- Contributed by James Demmel, Deaglan Halligan, Yozo Hida and --
* -- Jason Riedy of Univ. of California Berkeley. --
* -- November 2008 --
*
* -- LAPACK is a software package provided by Univ. of Tennessee, --
* -- Univ. of California Berkeley and NAG Ltd. --
*
IMPLICIT NONE
* ..
* .. Scalar Arguments ..
INTEGER M, N, LDX
* ..
* .. Array Arguments ..
COMPLEX*16 X( LDX, * )
DOUBLE PRECISION D( * )
* ..
*
* Purpose
* =======
*
* ZLARSCL2 performs a reciprocal diagonal scaling on an vector:
* x <-- inv(D) * x
* where the DOUBLE PRECISION diagonal matrix D is stored as a vector.
*
* Eventually to be replaced by BLAS_zge_diag_scale in the new BLAS
* standard.
*
* Arguments
* =========
*
* M (input) INTEGER
* The number of rows of D and X. M >= 0.
*
* N (input) INTEGER
* The number of columns of D and X. N >= 0.
*
* D (input) DOUBLE PRECISION array, length M
* Diagonal matrix D, stored as a vector of length M.
*
* X (input/output) COMPLEX*16 array, dimension (LDX,N)
* On entry, the vector X to be scaled by D.
* On exit, the scaled vector.
*
* LDX (input) INTEGER
* The leading dimension of the vector X. LDX >= 0.
*
* =====================================================================
*
* .. Local Scalars ..
INTEGER I, J
* ..
* .. Executable Statements ..
*
DO J = 1, N
DO I = 1, M
X( I, J ) = X( I, J ) / D( I )
END DO
END DO
RETURN
END
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