zgetc2.f man page

zgetc2.f

Synopsis

Functions/Subroutines

subroutine zgetc2 (N, A, LDA, IPIV, JPIV, INFO)
ZGETC2 computes the LU factorization with complete pivoting of the general n-by-n matrix.

Function/Subroutine Documentation

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.

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:

N

```          N is INTEGER
The order of the matrix A. N >= 0.```

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.```

LDA

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

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).```

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).```

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

NAG Ltd.

Date:

June 2016

Contributors:

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

Definition at line 113 of file zgetc2.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

The man page zgetc2(3) is an alias of zgetc2.f(3).

Tue Nov 14 2017 Version 3.8.0 LAPACK