zla_porcond_x()

double precision function zla_porcond_x	(	character	uplo,
		integer	n,
		complex*16, dimension( lda, * )	a,
		integer	lda,
		complex*16, dimension( ldaf, * )	af,
		integer	ldaf,
		complex*16, dimension( * )	x,
		integer	info,
		complex*16, dimension( * )	work,
		double precision, dimension( * )	rwork
	)

ZLA_PORCOND_X computes the infinity norm condition number of op(A)*diag(x) for Hermitian positive-definite matrices.

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Purpose:

    ZLA_PORCOND_X Computes the infinity norm condition number of
    op(A) * diag(X) where X is a COMPLEX*16 vector.

Parameters

[in]	UPLO	UPLO is CHARACTER*1 = 'U': Upper triangle of A is stored; = 'L': Lower triangle of A is stored.
[in]	N	N is INTEGER The number of linear equations, i.e., the order of the matrix A. N >= 0.
[in]	A	A is COMPLEX*16 array, dimension (LDA,N) On entry, the N-by-N matrix A.
[in]	LDA	LDA is INTEGER The leading dimension of the array A. LDA >= max(1,N).
[in]	AF	AF is COMPLEX*16 array, dimension (LDAF,N) The triangular factor U or L from the Cholesky factorization A = U**H*U or A = L*L**H, as computed by ZPOTRF.
[in]	LDAF	LDAF is INTEGER The leading dimension of the array AF. LDAF >= max(1,N).
[in]	X	X is COMPLEX*16 array, dimension (N) The vector X in the formula op(A) * diag(X).
[out]	INFO	INFO is INTEGER = 0: Successful exit. i > 0: The ith argument is invalid.
[out]	WORK	WORK is COMPLEX*16 array, dimension (2*N). Workspace.
[out]	RWORK	RWORK is DOUBLE PRECISION array, dimension (N). Workspace.

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.