Flashnux

GNU/Linux man pages

Livre :
Expressions régulières,
Syntaxe et mise en oeuvre :

ISBN : 978-2-7460-9712-4
EAN : 9782746097124
(Editions ENI)

GNU/Linux

CentOS 4.8

 i386

zlaqhe(l)
ZLAQHE

ZLAQHE

NAME
SYNOPSIS
PURPOSE
ARGUMENTS
PARAMETERS

NAME

ZLAQHE - equilibrate a Hermitian matrix A using the scaling factors in the vector S

SYNOPSIS

SUBROUTINE ZLAQHE(

UPLO, N, A, LDA, S, SCOND, AMAX, EQUED )

CHARACTER

EQUED, UPLO

INTEGER

LDA, N

DOUBLE

PRECISION AMAX, SCOND

DOUBLE

PRECISION S( * )

COMPLEX*16

A( LDA, * )

PURPOSE

ZLAQHE equilibrates a Hermitian matrix A using the scaling factors in the vector S.

ARGUMENTS

UPLO (input) CHARACTER*1

Specifies whether the upper or lower triangular part of the Hermitian matrix A is stored. = ’U’: Upper triangular
= ’L’: Lower triangular

N (input) INTEGER

The order of the matrix A. N >= 0.

A (input/output) COMPLEX*16 array, dimension (LDA,N)

On entry, the Hermitian matrix A. If UPLO = ’U’, the leading n by n upper triangular part of A contains the upper triangular part of the matrix A, and the strictly lower triangular part of A is not referenced. If UPLO = ’L’, the leading n by n lower triangular part of A contains the lower triangular part of the matrix A, and the strictly upper triangular part of A is not referenced.

On exit, if EQUED = ’Y’, the equilibrated matrix: diag(S) * A * diag(S).

LDA (input) INTEGER

The leading dimension of the array A. LDA >= max(N,1).

S (input) DOUBLE PRECISION array, dimension (N)

The scale factors for A.

SCOND (input) DOUBLE PRECISION

Ratio of the smallest S(i) to the largest S(i).

AMAX (input) DOUBLE PRECISION

Absolute value of largest matrix entry.

EQUED (output) CHARACTER*1

Specifies whether or not equilibration was done. = ’N’: No equilibration.
= ’Y’: Equilibration was done, i.e., A has been replaced by diag(S) * A * diag(S).

PARAMETERS

THRESH is a threshold value used to decide if scaling should be done based on the ratio of the scaling factors. If SCOND < THRESH, scaling is done.

LARGE and SMALL are threshold values used to decide if scaling should be done based on the absolute size of the largest matrix element. If AMAX > LARGE or AMAX < SMALL, scaling is done.

zlaqhe(l)