NAME¶

DLARSCL2 - performs a reciprocal diagonal scaling on an vector

SYNOPSIS¶

SUBROUTINE DLARSCL2

( M, N, D, X, LDX )

IMPLICIT NONE INTEGER M, N, LDX DOUBLE PRECISION D( * ), X( LDX, * )

PURPOSE¶

DLARSCL2 performs a reciprocal diagonal scaling on an vector:
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.

ARGUMENTS¶

N (input) INTEGER

The size of the vectors X and D.

D (input) DOUBLE PRECISION array, length N

Diagonal matrix D, stored as a vector of length N.

X (input/output) DOUBLE PRECISION array, length N

On entry, the vector X to be scaled by D. On exit, the scaled vector.