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version 1.9, 2011/11/21 22:19:46
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*> \brief \b ZGETF2 |
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* |
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* =========== DOCUMENTATION =========== |
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* |
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* Online html documentation available at |
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* http://www.netlib.org/lapack/explore-html/ |
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* |
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*> \htmlonly |
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*> Download ZGETF2 + dependencies |
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*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/zgetf2.f"> |
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*> [TGZ]</a> |
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*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/zgetf2.f"> |
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*> [ZIP]</a> |
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*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/zgetf2.f"> |
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*> [TXT]</a> |
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*> \endhtmlonly |
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* |
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* Definition: |
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* =========== |
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* |
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* SUBROUTINE ZGETF2( M, N, A, LDA, IPIV, INFO ) |
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* |
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* .. Scalar Arguments .. |
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* INTEGER INFO, LDA, M, N |
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* .. |
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* .. Array Arguments .. |
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* INTEGER IPIV( * ) |
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* COMPLEX*16 A( LDA, * ) |
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* .. |
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* |
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* |
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*> \par Purpose: |
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* ============= |
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*> |
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*> \verbatim |
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*> |
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*> ZGETF2 computes an LU factorization of a general m-by-n matrix A |
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*> using partial pivoting with row interchanges. |
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*> |
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*> The factorization has the form |
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*> A = P * L * U |
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*> where P is a permutation matrix, L is lower triangular with unit |
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*> diagonal elements (lower trapezoidal if m > n), and U is upper |
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*> triangular (upper trapezoidal if m < n). |
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*> |
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*> This is the right-looking Level 2 BLAS version of the algorithm. |
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*> \endverbatim |
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* |
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* Arguments: |
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* ========== |
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* |
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*> \param[in] M |
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*> \verbatim |
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*> M is INTEGER |
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*> The number of rows of the matrix A. M >= 0. |
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*> \endverbatim |
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*> |
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*> \param[in] N |
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*> \verbatim |
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*> N is INTEGER |
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*> The number of columns of the matrix A. N >= 0. |
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*> \endverbatim |
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*> |
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*> \param[in,out] A |
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*> \verbatim |
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*> A is COMPLEX*16 array, dimension (LDA,N) |
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*> On entry, the m by n matrix to be factored. |
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*> On exit, the factors L and U from the factorization |
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*> A = P*L*U; the unit diagonal elements of L are not stored. |
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*> \endverbatim |
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*> |
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*> \param[in] LDA |
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*> \verbatim |
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*> LDA is INTEGER |
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*> The leading dimension of the array A. LDA >= max(1,M). |
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*> \endverbatim |
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*> |
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*> \param[out] IPIV |
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*> \verbatim |
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*> IPIV is INTEGER array, dimension (min(M,N)) |
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*> The pivot indices; for 1 <= i <= min(M,N), row i of the |
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*> matrix was interchanged with row IPIV(i). |
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*> \endverbatim |
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*> |
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*> \param[out] INFO |
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*> \verbatim |
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*> INFO is INTEGER |
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*> = 0: successful exit |
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*> < 0: if INFO = -k, the k-th argument had an illegal value |
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*> > 0: if INFO = k, U(k,k) is exactly zero. The factorization |
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*> has been completed, but the factor U is exactly |
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*> singular, and division by zero will occur if it is used |
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*> to solve a system of equations. |
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*> \endverbatim |
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* |
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* Authors: |
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* ======== |
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* |
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*> \author Univ. of Tennessee |
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*> \author Univ. of California Berkeley |
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*> \author Univ. of Colorado Denver |
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*> \author NAG Ltd. |
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* |
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*> \date November 2011 |
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* |
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*> \ingroup complex16GEcomputational |
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* |
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* ===================================================================== |
SUBROUTINE ZGETF2( M, N, A, LDA, IPIV, INFO ) |
SUBROUTINE ZGETF2( M, N, A, LDA, IPIV, INFO ) |
* |
* |
* -- LAPACK routine (version 3.2) -- |
* -- LAPACK computational routine (version 3.4.0) -- |
* -- LAPACK is a software package provided by Univ. of Tennessee, -- |
* -- LAPACK is a software package provided by Univ. of Tennessee, -- |
* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- |
* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- |
* November 2006 |
* November 2011 |
* |
* |
* .. Scalar Arguments .. |
* .. Scalar Arguments .. |
INTEGER INFO, LDA, M, N |
INTEGER INFO, LDA, M, N |
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COMPLEX*16 A( LDA, * ) |
COMPLEX*16 A( LDA, * ) |
* .. |
* .. |
* |
* |
* Purpose |
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* ======= |
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* |
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* ZGETF2 computes an LU factorization of a general m-by-n matrix A |
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* using partial pivoting with row interchanges. |
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* |
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* The factorization has the form |
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* A = P * L * U |
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* where P is a permutation matrix, L is lower triangular with unit |
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* diagonal elements (lower trapezoidal if m > n), and U is upper |
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* triangular (upper trapezoidal if m < n). |
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* |
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* This is the right-looking Level 2 BLAS version of the algorithm. |
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* |
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* Arguments |
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* ========= |
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* |
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* M (input) INTEGER |
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* The number of rows of the matrix A. M >= 0. |
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* |
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* N (input) INTEGER |
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* The number of columns of the matrix A. N >= 0. |
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* |
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* A (input/output) COMPLEX*16 array, dimension (LDA,N) |
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* On entry, the m by n matrix to be factored. |
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* On exit, the factors L and U from the factorization |
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* A = P*L*U; the unit diagonal elements of L are not stored. |
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* |
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* LDA (input) INTEGER |
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* The leading dimension of the array A. LDA >= max(1,M). |
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* |
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* IPIV (output) INTEGER array, dimension (min(M,N)) |
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* The pivot indices; for 1 <= i <= min(M,N), row i of the |
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* matrix was interchanged with row IPIV(i). |
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* |
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* INFO (output) INTEGER |
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* = 0: successful exit |
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* < 0: if INFO = -k, the k-th argument had an illegal value |
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* > 0: if INFO = k, U(k,k) is exactly zero. The factorization |
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* has been completed, but the factor U is exactly |
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* singular, and division by zero will occur if it is used |
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* to solve a system of equations. |
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* |
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* ===================================================================== |
* ===================================================================== |
* |
* |
* .. Parameters .. |
* .. Parameters .. |