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* =========== DOCUMENTATION ===========
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* Online html documentation available at
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* http://www.netlib.org/lapack/explore-html/
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*> Download DGETRF + dependencies
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*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/dgetrf.f">
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*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/dgetrf.f">
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*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/dgetrf.f">
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* SUBROUTINE DGETRF( M, N, A, LDA, IPIV, INFO )
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* .. Scalar Arguments ..
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* INTEGER INFO, LDA, M, N
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* .. Array Arguments ..
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* DOUBLE PRECISION A( LDA, * )
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*> DGETRF 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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*> The factorization has the form
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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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*> This is the right-looking Level 3 BLAS version of the algorithm.
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*> The number of rows of the matrix A. M >= 0.
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*> The number of columns of the matrix A. N >= 0.
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*> A is DOUBLE PRECISION 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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*> The leading dimension of the array A. LDA >= max(1,M).
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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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*> = 0: successful exit
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*> < 0: if INFO = -i, the i-th argument had an illegal value
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*> > 0: if INFO = i, U(i,i) 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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*> \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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*> \date November 2011
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*> \ingroup doubleGEcomputational
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* =====================================================================
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SUBROUTINE DGETRF( M, N, A, LDA, IPIV, INFO )
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* -- LAPACK routine (version 2.0) --
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* Univ. of Tennessee, Univ. of California Berkeley, NAG Ltd.,
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* Courant Institute, Argonne National Lab, and Rice University
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* -- LAPACK computational routine (version 3.4.0) --
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* -- LAPACK is a software package provided by Univ. of Tennessee, --
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* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
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* .. Scalar Arguments ..
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INTEGER INFO, LDA, M, N
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DOUBLE PRECISION A( LDA, * )
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* $Id: dgetrf.f 19697 2010-10-29 16:57:34Z d3y133 $
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* DGETRF 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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* The factorization has the form
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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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* This is the right-looking Level 3 BLAS version of the algorithm.
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* The number of rows of the matrix A. M >= 0.
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* The number of columns of the matrix A. N >= 0.
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* A (input/output) DOUBLE PRECISION 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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* The leading dimension of the array A. LDA >= max(1,M).
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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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* INFO (output) INTEGER
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* = 0: successful exit
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* < 0: if INFO = -i, the i-th argument had an illegal value
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* > 0: if INFO = i, U(i,i) 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 ..