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Livre :
Expressions régulières,
Syntaxe et mise en oeuvre :

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

GNU/Linux	CentOS 4.8	i386
	chetri(l)

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CHETRI

NAME
SYNOPSIS
PURPOSE
ARGUMENTS

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NAME

CHETRI - compute the inverse of a complex Hermitian indefinite matrix A using the factorization A = U*D*U**H or A = L*D*L**H computed by CHETRF

SYNOPSIS

	SUBROUTINE CHETRI(		UPLO, N, A, LDA, IPIV, WORK, INFO )
	CHARACTER		UPLO
	INTEGER		INFO, LDA, N
	INTEGER		IPIV( * )
	COMPLEX		A( LDA, * ), WORK( * )

PURPOSE

CHETRI computes the inverse of a complex Hermitian indefinite matrix A using the factorization A = U*D*U**H or A = L*D*L**H computed by CHETRF.

ARGUMENTS

UPLO (input) CHARACTER*1

Specifies whether the details of the factorization are stored as an upper or lower triangular matrix. = ’U’: Upper triangular, form is A = U*D*U**H;
= ’L’: Lower triangular, form is A = L*D*L**H.

N (input) INTEGER

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

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

On entry, the block diagonal matrix D and the multipliers used to obtain the factor U or L as computed by CHETRF.

On exit, if INFO = 0, the (Hermitian) inverse of the original matrix. If UPLO = ’U’, the upper triangular part of the inverse is formed and the part of A below the diagonal is not referenced; if UPLO = ’L’ the lower triangular part of the inverse is formed and the part of A above the diagonal is not referenced.

LDA (input) INTEGER

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

IPIV (input) INTEGER array, dimension (N)

Details of the interchanges and the block structure of D as determined by CHETRF.

WORK (workspace) COMPLEX array, dimension (N)
INFO (output) INTEGER

= 0: successful exit
< 0: if INFO = -i, the i-th argument had an illegal value
> 0: if INFO = i, D(i,i) = 0; the matrix is singular and its inverse could not be computed.

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chetri(l)