SRC/zlaqge.f(3) | Library Functions Manual | SRC/zlaqge.f(3) |
NAME
SRC/zlaqge.f
SYNOPSIS
Functions/Subroutines
subroutine zlaqge (m, n, a, lda, r, c, rowcnd, colcnd,
amax, equed)
ZLAQGE scales a general rectangular matrix, using row and column
scaling factors computed by sgeequ.
Function/Subroutine Documentation
subroutine zlaqge (integer m, integer n, complex*16, dimension( lda, * ) a, integer lda, double precision, dimension( * ) r, double precision, dimension( * ) c, double precision rowcnd, double precision colcnd, double precision amax, character equed)
ZLAQGE scales a general rectangular matrix, using row and column scaling factors computed by sgeequ.
Purpose:
ZLAQGE equilibrates a general M by N matrix A using the row and column scaling factors in the vectors R and C.
Parameters
M
M is INTEGER The number of rows of the matrix A. M >= 0.
N
N is INTEGER The number of columns of the matrix A. N >= 0.
A
A is COMPLEX*16 array, dimension (LDA,N) On entry, the M by N matrix A. On exit, the equilibrated matrix. See EQUED for the form of the equilibrated matrix.
LDA
LDA is INTEGER The leading dimension of the array A. LDA >= max(M,1).
R
R is DOUBLE PRECISION array, dimension (M) The row scale factors for A.
C
C is DOUBLE PRECISION array, dimension (N) The column scale factors for A.
ROWCND
ROWCND is DOUBLE PRECISION Ratio of the smallest R(i) to the largest R(i).
COLCND
COLCND is DOUBLE PRECISION Ratio of the smallest C(i) to the largest C(i).
AMAX
AMAX is DOUBLE PRECISION Absolute value of largest matrix entry.
EQUED
EQUED is CHARACTER*1 Specifies the form of equilibration that was done. = 'N': No equilibration = 'R': Row equilibration, i.e., A has been premultiplied by diag(R). = 'C': Column equilibration, i.e., A has been postmultiplied by diag(C). = 'B': Both row and column equilibration, i.e., A has been replaced by diag(R) * A * diag(C).
Internal Parameters:
THRESH is a threshold value used to decide if row or column scaling should be done based on the ratio of the row or column scaling factors. If ROWCND < THRESH, row scaling is done, and if COLCND < THRESH, column scaling is done. LARGE and SMALL are threshold values used to decide if row scaling should be done based on the absolute size of the largest matrix element. If AMAX > LARGE or AMAX < SMALL, row scaling is done.
Author
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
NAG Ltd.
Definition at line 141 of file zlaqge.f.
Author
Generated automatically by Doxygen for LAPACK from the source code.
Version 3.12.0 | LAPACK |