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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
	zhpcon(l)

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ZHPCON

NAME
SYNOPSIS
PURPOSE
ARGUMENTS

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NAME

ZHPCON - estimate the reciprocal of the condition number of a complex Hermitian packed matrix A using the factorization A = U*D*U**H or A = L*D*L**H computed by ZHPTRF

SYNOPSIS

	SUBROUTINE ZHPCON(		UPLO, N, AP, IPIV, ANORM, RCOND, WORK, INFO )
	CHARACTER		UPLO
	INTEGER		INFO, N
	DOUBLE		PRECISION ANORM, RCOND
	INTEGER		IPIV( * )
	COMPLEX*16		AP( * ), WORK( * )

PURPOSE

ZHPCON estimates the reciprocal of the condition number of a complex Hermitian packed matrix A using the factorization A = U*D*U**H or A = L*D*L**H computed by ZHPTRF. An estimate is obtained for norm(inv(A)), and the reciprocal of the condition number is computed as RCOND = 1 / (ANORM * norm(inv(A))).

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.

AP (input) COMPLEX*16 array, dimension (N*(N+1)/2)

The block diagonal matrix D and the multipliers used to obtain the factor U or L as computed by ZHPTRF, stored as a packed triangular matrix.

IPIV (input) INTEGER array, dimension (N)

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

ANORM (input) DOUBLE PRECISION

The 1-norm of the original matrix A.

RCOND (output) DOUBLE PRECISION

The reciprocal of the condition number of the matrix A, computed as RCOND = 1/(ANORM * AINVNM), where AINVNM is an estimate of the 1-norm of inv(A) computed in this routine.

WORK (workspace) COMPLEX*16 array, dimension (2*N)
INFO (output) INTEGER

= 0: successful exit
< 0: if INFO = -i, the i-th argument had an illegal value

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zhpcon(l)