zgetc2()

subroutine zgetc2	(	integer	n,
		complex*16, dimension( lda, * )	a,
		integer	lda,
		integer, dimension( * )	ipiv,
		integer, dimension( * )	jpiv,
		integer	info )

ZGETC2 computes the LU factorization with complete pivoting of the general n-by-n matrix.

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Purpose:

!>
!> ZGETC2 computes an LU factorization, using complete pivoting, of the
!> n-by-n matrix A. The factorization has the form A = P * L * U * Q,
!> where P and Q are permutation matrices, L is lower triangular with
!> unit diagonal elements and U is upper triangular.
!>
!> This is a level 1 BLAS version of the algorithm.
!> 

Parameters

[in]	N	!> N is INTEGER !> The order of the matrix A. N >= 0. !>
[in,out]	A	!> A is COMPLEX*16 array, dimension (LDA, N) !> On entry, the n-by-n matrix to be factored. !> On exit, the factors L and U from the factorization !> A = P*L*U*Q; the unit diagonal elements of L are not stored. !> If U(k, k) appears to be less than SMIN, U(k, k) is given the !> value of SMIN, giving a nonsingular perturbed system. !>
[in]	LDA	!> LDA is INTEGER !> The leading dimension of the array A. LDA >= max(1, N). !>
[out]	IPIV	!> IPIV is INTEGER array, dimension (N). !> The pivot indices; for 1 <= i <= N, row i of the !> matrix has been interchanged with row IPIV(i). !>
[out]	JPIV	!> JPIV is INTEGER array, dimension (N). !> The pivot indices; for 1 <= j <= N, column j of the !> matrix has been interchanged with column JPIV(j). !>
[out]	INFO	!> INFO is INTEGER !> = 0: successful exit !> > 0: if INFO = k, U(k, k) is likely to produce overflow if !> one tries to solve for x in Ax = b. So U is perturbed !> to avoid the overflow. !>

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Contributors:

Bo Kagstrom and Peter Poromaa, Department of Computing Science, Umea University, S-901 87 Umea, Sweden.