removed lapack 3.6.0
This commit is contained in:
@@ -1,479 +0,0 @@
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*> \brief <b> SGELSY solves overdetermined or underdetermined systems for GE matrices</b>
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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 SGELSY + dependencies
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*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/sgelsy.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/sgelsy.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/sgelsy.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 SGELSY( M, N, NRHS, A, LDA, B, LDB, JPVT, RCOND, RANK,
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* WORK, LWORK, INFO )
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*
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* .. Scalar Arguments ..
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* INTEGER INFO, LDA, LDB, LWORK, M, N, NRHS, RANK
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* REAL RCOND
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* ..
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* .. Array Arguments ..
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* INTEGER JPVT( * )
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* REAL A( LDA, * ), B( LDB, * ), WORK( * )
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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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*> SGELSY computes the minimum-norm solution to a real linear least
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*> squares problem:
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*> minimize || A * X - B ||
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*> using a complete orthogonal factorization of A. A is an M-by-N
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*> matrix which may be rank-deficient.
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*>
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*> Several right hand side vectors b and solution vectors x can be
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*> handled in a single call; they are stored as the columns of the
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*> M-by-NRHS right hand side matrix B and the N-by-NRHS solution
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*> matrix X.
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*>
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*> The routine first computes a QR factorization with column pivoting:
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*> A * P = Q * [ R11 R12 ]
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*> [ 0 R22 ]
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*> with R11 defined as the largest leading submatrix whose estimated
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*> condition number is less than 1/RCOND. The order of R11, RANK,
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*> is the effective rank of A.
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*>
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*> Then, R22 is considered to be negligible, and R12 is annihilated
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*> by orthogonal transformations from the right, arriving at the
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*> complete orthogonal factorization:
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*> A * P = Q * [ T11 0 ] * Z
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*> [ 0 0 ]
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*> The minimum-norm solution is then
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*> X = P * Z**T [ inv(T11)*Q1**T*B ]
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*> [ 0 ]
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*> where Q1 consists of the first RANK columns of Q.
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*>
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*> This routine is basically identical to the original xGELSX except
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*> three differences:
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*> o The call to the subroutine xGEQPF has been substituted by the
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*> the call to the subroutine xGEQP3. This subroutine is a Blas-3
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*> version of the QR factorization with column pivoting.
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*> o Matrix B (the right hand side) is updated with Blas-3.
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*> o The permutation of matrix B (the right hand side) is faster and
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*> more simple.
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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] NRHS
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*> \verbatim
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*> NRHS is INTEGER
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*> The number of right hand sides, i.e., the number of
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*> columns of matrices B and X. NRHS >= 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 REAL array, dimension (LDA,N)
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*> On entry, the M-by-N matrix A.
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*> On exit, A has been overwritten by details of its
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*> complete orthogonal factorization.
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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[in,out] B
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*> \verbatim
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*> B is REAL array, dimension (LDB,NRHS)
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*> On entry, the M-by-NRHS right hand side matrix B.
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*> On exit, the N-by-NRHS solution matrix X.
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*> \endverbatim
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*>
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*> \param[in] LDB
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*> \verbatim
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*> LDB is INTEGER
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*> The leading dimension of the array B. LDB >= max(1,M,N).
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*> \endverbatim
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*>
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*> \param[in,out] JPVT
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*> \verbatim
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*> JPVT is INTEGER array, dimension (N)
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*> On entry, if JPVT(i) .ne. 0, the i-th column of A is permuted
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*> to the front of AP, otherwise column i is a free column.
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*> On exit, if JPVT(i) = k, then the i-th column of AP
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*> was the k-th column of A.
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*> \endverbatim
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*>
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*> \param[in] RCOND
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*> \verbatim
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*> RCOND is REAL
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*> RCOND is used to determine the effective rank of A, which
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*> is defined as the order of the largest leading triangular
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*> submatrix R11 in the QR factorization with pivoting of A,
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*> whose estimated condition number < 1/RCOND.
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*> \endverbatim
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*>
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*> \param[out] RANK
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*> \verbatim
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*> RANK is INTEGER
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*> The effective rank of A, i.e., the order of the submatrix
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*> R11. This is the same as the order of the submatrix T11
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*> in the complete orthogonal factorization of A.
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*> \endverbatim
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*>
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*> \param[out] WORK
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*> \verbatim
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*> WORK is REAL array, dimension (MAX(1,LWORK))
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*> On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
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*> \endverbatim
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*>
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*> \param[in] LWORK
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*> \verbatim
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*> LWORK is INTEGER
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*> The dimension of the array WORK.
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*> The unblocked strategy requires that:
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*> LWORK >= MAX( MN+3*N+1, 2*MN+NRHS ),
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*> where MN = min( M, N ).
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*> The block algorithm requires that:
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*> LWORK >= MAX( MN+2*N+NB*(N+1), 2*MN+NB*NRHS ),
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*> where NB is an upper bound on the blocksize returned
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*> by ILAENV for the routines SGEQP3, STZRZF, STZRQF, SORMQR,
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*> and SORMRZ.
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*>
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*> If LWORK = -1, then a workspace query is assumed; the routine
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*> only calculates the optimal size of the WORK array, returns
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*> this value as the first entry of the WORK array, and no error
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*> message related to LWORK is issued by XERBLA.
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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 = -i, the i-th argument had an illegal value.
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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 realGEsolve
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*
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*> \par Contributors:
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* ==================
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*>
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*> A. Petitet, Computer Science Dept., Univ. of Tenn., Knoxville, USA \n
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*> E. Quintana-Orti, Depto. de Informatica, Universidad Jaime I, Spain \n
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*> G. Quintana-Orti, Depto. de Informatica, Universidad Jaime I, Spain \n
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*>
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* =====================================================================
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SUBROUTINE SGELSY( M, N, NRHS, A, LDA, B, LDB, JPVT, RCOND, RANK,
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$ WORK, LWORK, INFO )
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*
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* -- LAPACK driver 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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* November 2011
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*
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* .. Scalar Arguments ..
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INTEGER INFO, LDA, LDB, LWORK, M, N, NRHS, RANK
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REAL RCOND
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* ..
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* .. Array Arguments ..
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INTEGER JPVT( * )
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REAL A( LDA, * ), B( LDB, * ), WORK( * )
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* ..
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*
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* =====================================================================
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*
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* .. Parameters ..
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INTEGER IMAX, IMIN
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PARAMETER ( IMAX = 1, IMIN = 2 )
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REAL ZERO, ONE
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PARAMETER ( ZERO = 0.0E+0, ONE = 1.0E+0 )
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* ..
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* .. Local Scalars ..
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LOGICAL LQUERY
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INTEGER I, IASCL, IBSCL, ISMAX, ISMIN, J, LWKMIN,
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$ LWKOPT, MN, NB, NB1, NB2, NB3, NB4
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REAL ANRM, BIGNUM, BNRM, C1, C2, S1, S2, SMAX,
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$ SMAXPR, SMIN, SMINPR, SMLNUM, WSIZE
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* ..
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* .. External Functions ..
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INTEGER ILAENV
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REAL SLAMCH, SLANGE
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EXTERNAL ILAENV, SLAMCH, SLANGE
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* ..
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* .. External Subroutines ..
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EXTERNAL SCOPY, SGEQP3, SLABAD, SLAIC1, SLASCL, SLASET,
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$ SORMQR, SORMRZ, STRSM, STZRZF, XERBLA
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* ..
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* .. Intrinsic Functions ..
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INTRINSIC ABS, MAX, MIN
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* ..
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* .. Executable Statements ..
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*
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MN = MIN( M, N )
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ISMIN = MN + 1
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ISMAX = 2*MN + 1
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*
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* Test the input arguments.
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*
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INFO = 0
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LQUERY = ( LWORK.EQ.-1 )
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IF( M.LT.0 ) THEN
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INFO = -1
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ELSE IF( N.LT.0 ) THEN
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INFO = -2
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ELSE IF( NRHS.LT.0 ) THEN
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INFO = -3
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ELSE IF( LDA.LT.MAX( 1, M ) ) THEN
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INFO = -5
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ELSE IF( LDB.LT.MAX( 1, M, N ) ) THEN
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INFO = -7
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END IF
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*
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* Figure out optimal block size
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*
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IF( INFO.EQ.0 ) THEN
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IF( MN.EQ.0 .OR. NRHS.EQ.0 ) THEN
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LWKMIN = 1
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LWKOPT = 1
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ELSE
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NB1 = ILAENV( 1, 'SGEQRF', ' ', M, N, -1, -1 )
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NB2 = ILAENV( 1, 'SGERQF', ' ', M, N, -1, -1 )
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NB3 = ILAENV( 1, 'SORMQR', ' ', M, N, NRHS, -1 )
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NB4 = ILAENV( 1, 'SORMRQ', ' ', M, N, NRHS, -1 )
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NB = MAX( NB1, NB2, NB3, NB4 )
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LWKMIN = MN + MAX( 2*MN, N + 1, MN + NRHS )
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LWKOPT = MAX( LWKMIN,
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$ MN + 2*N + NB*( N + 1 ), 2*MN + NB*NRHS )
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END IF
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WORK( 1 ) = LWKOPT
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*
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IF( LWORK.LT.LWKMIN .AND. .NOT.LQUERY ) THEN
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INFO = -12
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END IF
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END IF
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*
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IF( INFO.NE.0 ) THEN
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CALL XERBLA( 'SGELSY', -INFO )
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RETURN
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ELSE IF( LQUERY ) THEN
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RETURN
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END IF
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*
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* Quick return if possible
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*
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IF( MN.EQ.0 .OR. NRHS.EQ.0 ) THEN
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RANK = 0
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RETURN
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END IF
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*
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* Get machine parameters
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*
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SMLNUM = SLAMCH( 'S' ) / SLAMCH( 'P' )
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BIGNUM = ONE / SMLNUM
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CALL SLABAD( SMLNUM, BIGNUM )
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*
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* Scale A, B if max entries outside range [SMLNUM,BIGNUM]
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*
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ANRM = SLANGE( 'M', M, N, A, LDA, WORK )
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IASCL = 0
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IF( ANRM.GT.ZERO .AND. ANRM.LT.SMLNUM ) THEN
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*
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* Scale matrix norm up to SMLNUM
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*
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CALL SLASCL( 'G', 0, 0, ANRM, SMLNUM, M, N, A, LDA, INFO )
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IASCL = 1
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ELSE IF( ANRM.GT.BIGNUM ) THEN
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*
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* Scale matrix norm down to BIGNUM
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*
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CALL SLASCL( 'G', 0, 0, ANRM, BIGNUM, M, N, A, LDA, INFO )
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IASCL = 2
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ELSE IF( ANRM.EQ.ZERO ) THEN
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*
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* Matrix all zero. Return zero solution.
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*
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CALL SLASET( 'F', MAX( M, N ), NRHS, ZERO, ZERO, B, LDB )
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RANK = 0
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GO TO 70
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END IF
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*
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BNRM = SLANGE( 'M', M, NRHS, B, LDB, WORK )
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IBSCL = 0
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IF( BNRM.GT.ZERO .AND. BNRM.LT.SMLNUM ) THEN
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*
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* Scale matrix norm up to SMLNUM
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*
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CALL SLASCL( 'G', 0, 0, BNRM, SMLNUM, M, NRHS, B, LDB, INFO )
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IBSCL = 1
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ELSE IF( BNRM.GT.BIGNUM ) THEN
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*
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* Scale matrix norm down to BIGNUM
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*
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CALL SLASCL( 'G', 0, 0, BNRM, BIGNUM, M, NRHS, B, LDB, INFO )
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IBSCL = 2
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END IF
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*
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* Compute QR factorization with column pivoting of A:
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* A * P = Q * R
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*
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CALL SGEQP3( M, N, A, LDA, JPVT, WORK( 1 ), WORK( MN+1 ),
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$ LWORK-MN, INFO )
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WSIZE = MN + WORK( MN+1 )
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*
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* workspace: MN+2*N+NB*(N+1).
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* Details of Householder rotations stored in WORK(1:MN).
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*
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* Determine RANK using incremental condition estimation
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*
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WORK( ISMIN ) = ONE
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WORK( ISMAX ) = ONE
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SMAX = ABS( A( 1, 1 ) )
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SMIN = SMAX
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IF( ABS( A( 1, 1 ) ).EQ.ZERO ) THEN
|
||||
RANK = 0
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CALL SLASET( 'F', MAX( M, N ), NRHS, ZERO, ZERO, B, LDB )
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GO TO 70
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ELSE
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RANK = 1
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||||
END IF
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||||
*
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10 CONTINUE
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||||
IF( RANK.LT.MN ) THEN
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||||
I = RANK + 1
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||||
CALL SLAIC1( IMIN, RANK, WORK( ISMIN ), SMIN, A( 1, I ),
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||||
$ A( I, I ), SMINPR, S1, C1 )
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||||
CALL SLAIC1( IMAX, RANK, WORK( ISMAX ), SMAX, A( 1, I ),
|
||||
$ A( I, I ), SMAXPR, S2, C2 )
|
||||
*
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||||
IF( SMAXPR*RCOND.LE.SMINPR ) THEN
|
||||
DO 20 I = 1, RANK
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||||
WORK( ISMIN+I-1 ) = S1*WORK( ISMIN+I-1 )
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||||
WORK( ISMAX+I-1 ) = S2*WORK( ISMAX+I-1 )
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||||
20 CONTINUE
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||||
WORK( ISMIN+RANK ) = C1
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||||
WORK( ISMAX+RANK ) = C2
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||||
SMIN = SMINPR
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||||
SMAX = SMAXPR
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||||
RANK = RANK + 1
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||||
GO TO 10
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||||
END IF
|
||||
END IF
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||||
*
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||||
* workspace: 3*MN.
|
||||
*
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||||
* Logically partition R = [ R11 R12 ]
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||||
* [ 0 R22 ]
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||||
* where R11 = R(1:RANK,1:RANK)
|
||||
*
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||||
* [R11,R12] = [ T11, 0 ] * Y
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||||
*
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||||
IF( RANK.LT.N )
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||||
$ CALL STZRZF( RANK, N, A, LDA, WORK( MN+1 ), WORK( 2*MN+1 ),
|
||||
$ LWORK-2*MN, INFO )
|
||||
*
|
||||
* workspace: 2*MN.
|
||||
* Details of Householder rotations stored in WORK(MN+1:2*MN)
|
||||
*
|
||||
* B(1:M,1:NRHS) := Q**T * B(1:M,1:NRHS)
|
||||
*
|
||||
CALL SORMQR( 'Left', 'Transpose', M, NRHS, MN, A, LDA, WORK( 1 ),
|
||||
$ B, LDB, WORK( 2*MN+1 ), LWORK-2*MN, INFO )
|
||||
WSIZE = MAX( WSIZE, 2*MN+WORK( 2*MN+1 ) )
|
||||
*
|
||||
* workspace: 2*MN+NB*NRHS.
|
||||
*
|
||||
* B(1:RANK,1:NRHS) := inv(T11) * B(1:RANK,1:NRHS)
|
||||
*
|
||||
CALL STRSM( 'Left', 'Upper', 'No transpose', 'Non-unit', RANK,
|
||||
$ NRHS, ONE, A, LDA, B, LDB )
|
||||
*
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||||
DO 40 J = 1, NRHS
|
||||
DO 30 I = RANK + 1, N
|
||||
B( I, J ) = ZERO
|
||||
30 CONTINUE
|
||||
40 CONTINUE
|
||||
*
|
||||
* B(1:N,1:NRHS) := Y**T * B(1:N,1:NRHS)
|
||||
*
|
||||
IF( RANK.LT.N ) THEN
|
||||
CALL SORMRZ( 'Left', 'Transpose', N, NRHS, RANK, N-RANK, A,
|
||||
$ LDA, WORK( MN+1 ), B, LDB, WORK( 2*MN+1 ),
|
||||
$ LWORK-2*MN, INFO )
|
||||
END IF
|
||||
*
|
||||
* workspace: 2*MN+NRHS.
|
||||
*
|
||||
* B(1:N,1:NRHS) := P * B(1:N,1:NRHS)
|
||||
*
|
||||
DO 60 J = 1, NRHS
|
||||
DO 50 I = 1, N
|
||||
WORK( JPVT( I ) ) = B( I, J )
|
||||
50 CONTINUE
|
||||
CALL SCOPY( N, WORK( 1 ), 1, B( 1, J ), 1 )
|
||||
60 CONTINUE
|
||||
*
|
||||
* workspace: N.
|
||||
*
|
||||
* Undo scaling
|
||||
*
|
||||
IF( IASCL.EQ.1 ) THEN
|
||||
CALL SLASCL( 'G', 0, 0, ANRM, SMLNUM, N, NRHS, B, LDB, INFO )
|
||||
CALL SLASCL( 'U', 0, 0, SMLNUM, ANRM, RANK, RANK, A, LDA,
|
||||
$ INFO )
|
||||
ELSE IF( IASCL.EQ.2 ) THEN
|
||||
CALL SLASCL( 'G', 0, 0, ANRM, BIGNUM, N, NRHS, B, LDB, INFO )
|
||||
CALL SLASCL( 'U', 0, 0, BIGNUM, ANRM, RANK, RANK, A, LDA,
|
||||
$ INFO )
|
||||
END IF
|
||||
IF( IBSCL.EQ.1 ) THEN
|
||||
CALL SLASCL( 'G', 0, 0, SMLNUM, BNRM, N, NRHS, B, LDB, INFO )
|
||||
ELSE IF( IBSCL.EQ.2 ) THEN
|
||||
CALL SLASCL( 'G', 0, 0, BIGNUM, BNRM, N, NRHS, B, LDB, INFO )
|
||||
END IF
|
||||
*
|
||||
70 CONTINUE
|
||||
WORK( 1 ) = LWKOPT
|
||||
*
|
||||
RETURN
|
||||
*
|
||||
* End of SGELSY
|
||||
*
|
||||
END
|
||||
Reference in New Issue
Block a user