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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 SPOTRF + dependencies
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*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/spotrf.f">
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*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/spotrf.f">
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*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/spotrf.f">
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* SUBROUTINE SPOTRF( UPLO, N, A, LDA, INFO )
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* .. Scalar Arguments ..
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* INTEGER INFO, LDA, N
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* .. Array Arguments ..
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*> SPOTRF computes the Cholesky factorization of a real symmetric
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*> positive definite matrix A.
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*> The factorization has the form
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*> A = U**T * U, if UPLO = 'U', or
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*> A = L * L**T, if UPLO = 'L',
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*> where U is an upper triangular matrix and L is lower triangular.
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*> This is the block version of the algorithm, calling Level 3 BLAS.
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*> UPLO is CHARACTER*1
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*> = 'U': Upper triangle of A is stored;
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*> = 'L': Lower triangle of A is stored.
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*> The order of the matrix A. N >= 0.
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*> A is REAL array, dimension (LDA,N)
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*> On entry, the symmetric matrix A. If UPLO = 'U', the leading
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*> N-by-N upper triangular part of A contains the upper
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*> triangular part of the matrix A, and the strictly lower
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*> triangular part of A is not referenced. If UPLO = 'L', the
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*> leading N-by-N lower triangular part of A contains the lower
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*> triangular part of the matrix A, and the strictly upper
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*> triangular part of A is not referenced.
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*> On exit, if INFO = 0, the factor U or L from the Cholesky
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*> factorization A = U**T*U or A = L*L**T.
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*> The leading dimension of the array A. LDA >= max(1,N).
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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, the leading minor of order i is not
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*> positive definite, and the factorization could not be
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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 realPOcomputational
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* =====================================================================
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SUBROUTINE SPOTRF( UPLO, N, A, LDA, 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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* $Id: spotrf.f 19697 2010-10-29 16:57:34Z d3y133 $
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* SPOTRF computes the Cholesky factorization of a real symmetric
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* positive definite matrix A.
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* The factorization has the form
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* A = U**T * U, if UPLO = 'U', or
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* A = L * L**T, if UPLO = 'L',
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* where U is an upper triangular matrix and L is lower triangular.
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* This is the block version of the algorithm, calling Level 3 BLAS.
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* UPLO (input) CHARACTER*1
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* = 'U': Upper triangle of A is stored;
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* = 'L': Lower triangle of A is stored.
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* The order of the matrix A. N >= 0.
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* A (input/output) REAL array, dimension (LDA,N)
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* On entry, the symmetric matrix A. If UPLO = 'U', the leading
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* N-by-N upper triangular part of A contains the upper
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* triangular part of the matrix A, and the strictly lower
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* triangular part of A is not referenced. If UPLO = 'L', the
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* leading N-by-N lower triangular part of A contains the lower
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* triangular part of the matrix A, and the strictly upper
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* triangular part of A is not referenced.
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* On exit, if INFO = 0, the factor U or L from the Cholesky
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* factorization A = U**T*U or A = L*L**T.
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* The leading dimension of the array A. LDA >= max(1,N).
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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, the leading minor of order i is not
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* positive definite, and the factorization could not be
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* =====================================================================
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* .. Parameters ..