dlarscl2()

subroutine dlarscl2	(	integer	m,
		integer	n,
		double precision, dimension( * )	d,
		double precision, dimension( ldx, * )	x,
		integer	ldx
	)

DLARSCL2 performs reciprocal diagonal scaling on a matrix.

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Purpose:

 DLARSCL2 performs a reciprocal diagonal scaling on a matrix:
   x <-- inv(D) * x
 where the diagonal matrix D is stored as a vector.

 Eventually to be replaced by BLAS_dge_diag_scale in the new BLAS
 standard.

Parameters

[in]	M	M is INTEGER The number of rows of D and X. M >= 0.
[in]	N	N is INTEGER The number of columns of X. N >= 0.
[in]	D	D is DOUBLE PRECISION array, dimension (M) Diagonal matrix D, stored as a vector of length M.
[in,out]	X	X is DOUBLE PRECISION array, dimension (LDX,N) On entry, the matrix X to be scaled by D. On exit, the scaled matrix.
[in]	LDX	LDX is INTEGER The leading dimension of the matrix X. LDX >= M.

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Definition at line 89 of file dlarscl2.f.

*
*  -- LAPACK computational routine --
*  -- LAPACK is a software package provided by Univ. of Tennessee,    --
*  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
*
*     .. Scalar Arguments ..
      INTEGER            M, N, LDX
*     ..
*     .. Array Arguments ..
      DOUBLE PRECISION   D( * ), X( LDX, * )
*     ..
*
*  =====================================================================
*
*     .. 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