LAPACK 3.11.0 LAPACK: Linear Algebra PACKage
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## ◆ slarscl2()

 subroutine slarscl2 ( integer M, integer N, real, dimension( * ) D, real, dimension( ldx, * ) X, integer LDX )

SLARSCL2 performs reciprocal diagonal scaling on a matrix.

Purpose:
``` SLARSCL2 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_sge_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 REAL array, length M Diagonal matrix D, stored as a vector of length M.``` [in,out] X ``` X is REAL 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.```

Definition at line 89 of file slarscl2.f.

90*
91* -- LAPACK computational routine --
92* -- LAPACK is a software package provided by Univ. of Tennessee, --
93* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
94*
95* .. Scalar Arguments ..
96 INTEGER M, N, LDX
97* ..
98* .. Array Arguments ..
99 REAL D( * ), X( LDX, * )
100* ..
101*
102* =====================================================================
103*
104* .. Local Scalars ..
105 INTEGER I, J
106* ..
107* .. Executable Statements ..
108*
109 DO j = 1, n
110 DO i = 1, m
111 x( i, j ) = x( i, j ) / d( i )
112 END DO
113 END DO
114
115 RETURN