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.