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author | julie <julielangou@users.noreply.github.com> | 2011-10-06 06:53:11 +0000 |
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committer | julie <julielangou@users.noreply.github.com> | 2011-10-06 06:53:11 +0000 |
commit | e1d39294aee16fa6db9ba079b14442358217db71 (patch) | |
tree | 30e5aa04c1f6596991fda5334f63dfb9b8027849 /SRC/dsyev.f | |
parent | 5fe0466a14e395641f4f8a300ecc9dcb8058081b (diff) | |
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Integrating Doxygen in comments
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-rw-r--r-- | SRC/dsyev.f | 187 |
1 files changed, 127 insertions, 60 deletions
diff --git a/SRC/dsyev.f b/SRC/dsyev.f index da208fb2..97290fc1 100644 --- a/SRC/dsyev.f +++ b/SRC/dsyev.f @@ -1,9 +1,134 @@ +*> \brief <b> DSYEV computes the eigenvalues and, optionally, the left and/or right eigenvectors for SY matrices</b> +* +* =========== DOCUMENTATION =========== +* +* Online html documentation available at +* http://www.netlib.org/lapack/explore-html/ +* +* Definition +* ========== +* +* SUBROUTINE DSYEV( JOBZ, UPLO, N, A, LDA, W, WORK, LWORK, INFO ) +* +* .. Scalar Arguments .. +* CHARACTER JOBZ, UPLO +* INTEGER INFO, LDA, LWORK, N +* .. +* .. Array Arguments .. +* DOUBLE PRECISION A( LDA, * ), W( * ), WORK( * ) +* .. +* +* Purpose +* ======= +* +*>\details \b Purpose: +*>\verbatim +*> +*> DSYEV computes all eigenvalues and, optionally, eigenvectors of a +*> real symmetric matrix A. +*> +*>\endverbatim +* +* Arguments +* ========= +* +*> \param[in] JOBZ +*> \verbatim +*> JOBZ is CHARACTER*1 +*> = 'N': Compute eigenvalues only; +*> = 'V': Compute eigenvalues and eigenvectors. +*> \endverbatim +*> +*> \param[in] UPLO +*> \verbatim +*> UPLO is CHARACTER*1 +*> = 'U': Upper triangle of A is stored; +*> = 'L': Lower triangle of A is stored. +*> \endverbatim +*> +*> \param[in] N +*> \verbatim +*> N is INTEGER +*> The order of the matrix A. N >= 0. +*> \endverbatim +*> +*> \param[in,out] A +*> \verbatim +*> A is DOUBLE PRECISION array, dimension (LDA, N) +*> On entry, the symmetric matrix A. If UPLO = 'U', the +*> leading N-by-N upper triangular part of A contains the +*> upper triangular part of the matrix A. If UPLO = 'L', +*> the leading N-by-N lower triangular part of A contains +*> the lower triangular part of the matrix A. +*> On exit, if JOBZ = 'V', then if INFO = 0, A contains the +*> orthonormal eigenvectors of the matrix A. +*> If JOBZ = 'N', then on exit the lower triangle (if UPLO='L') +*> or the upper triangle (if UPLO='U') of A, including the +*> diagonal, is destroyed. +*> \endverbatim +*> +*> \param[in] LDA +*> \verbatim +*> LDA is INTEGER +*> The leading dimension of the array A. LDA >= max(1,N). +*> \endverbatim +*> +*> \param[out] W +*> \verbatim +*> W is DOUBLE PRECISION array, dimension (N) +*> If INFO = 0, the eigenvalues in ascending order. +*> \endverbatim +*> +*> \param[out] WORK +*> \verbatim +*> WORK is DOUBLE PRECISION array, dimension (MAX(1,LWORK)) +*> On exit, if INFO = 0, WORK(1) returns the optimal LWORK. +*> \endverbatim +*> +*> \param[in] LWORK +*> \verbatim +*> LWORK is INTEGER +*> The length of the array WORK. LWORK >= max(1,3*N-1). +*> For optimal efficiency, LWORK >= (NB+2)*N, +*> where NB is the blocksize for DSYTRD returned by ILAENV. +*> \endverbatim +*> \verbatim +*> If LWORK = -1, then a workspace query is assumed; the routine +*> only calculates the optimal size of the WORK array, returns +*> this value as the first entry of the WORK array, and no error +*> message related to LWORK is issued by XERBLA. +*> \endverbatim +*> +*> \param[out] INFO +*> \verbatim +*> INFO is INTEGER +*> = 0: successful exit +*> < 0: if INFO = -i, the i-th argument had an illegal value +*> > 0: if INFO = i, the algorithm failed to converge; i +*> off-diagonal elements of an intermediate tridiagonal +*> form did not converge to zero. +*> \endverbatim +*> +* +* Authors +* ======= +* +*> \author Univ. of Tennessee +*> \author Univ. of California Berkeley +*> \author Univ. of Colorado Denver +*> \author NAG Ltd. +* +*> \date November 2011 +* +*> \ingroup doubleSYeigen +* +* ===================================================================== SUBROUTINE DSYEV( JOBZ, UPLO, N, A, LDA, W, WORK, LWORK, INFO ) * -* -- LAPACK driver routine (version 3.2) -- +* -- LAPACK eigen routine (version 3.2) -- * -- LAPACK is a software package provided by Univ. of Tennessee, -- * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- -* November 2006 +* November 2011 * * .. Scalar Arguments .. CHARACTER JOBZ, UPLO @@ -13,64 +138,6 @@ DOUBLE PRECISION A( LDA, * ), W( * ), WORK( * ) * .. * -* Purpose -* ======= -* -* DSYEV computes all eigenvalues and, optionally, eigenvectors of a -* real symmetric matrix A. -* -* Arguments -* ========= -* -* JOBZ (input) CHARACTER*1 -* = 'N': Compute eigenvalues only; -* = 'V': Compute eigenvalues and eigenvectors. -* -* UPLO (input) CHARACTER*1 -* = 'U': Upper triangle of A is stored; -* = 'L': Lower triangle of A is stored. -* -* N (input) INTEGER -* The order of the matrix A. N >= 0. -* -* A (input/output) DOUBLE PRECISION array, dimension (LDA, N) -* On entry, the symmetric matrix A. If UPLO = 'U', the -* leading N-by-N upper triangular part of A contains the -* upper triangular part of the matrix A. If UPLO = 'L', -* the leading N-by-N lower triangular part of A contains -* the lower triangular part of the matrix A. -* On exit, if JOBZ = 'V', then if INFO = 0, A contains the -* orthonormal eigenvectors of the matrix A. -* If JOBZ = 'N', then on exit the lower triangle (if UPLO='L') -* or the upper triangle (if UPLO='U') of A, including the -* diagonal, is destroyed. -* -* LDA (input) INTEGER -* The leading dimension of the array A. LDA >= max(1,N). -* -* W (output) DOUBLE PRECISION array, dimension (N) -* If INFO = 0, the eigenvalues in ascending order. -* -* WORK (workspace/output) DOUBLE PRECISION array, dimension (MAX(1,LWORK)) -* On exit, if INFO = 0, WORK(1) returns the optimal LWORK. -* -* LWORK (input) INTEGER -* The length of the array WORK. LWORK >= max(1,3*N-1). -* For optimal efficiency, LWORK >= (NB+2)*N, -* where NB is the blocksize for DSYTRD returned by ILAENV. -* -* If LWORK = -1, then a workspace query is assumed; the routine -* only calculates the optimal size of the WORK array, returns -* this value as the first entry of the WORK array, and no error -* message related to LWORK is issued by XERBLA. -* -* INFO (output) INTEGER -* = 0: successful exit -* < 0: if INFO = -i, the i-th argument had an illegal value -* > 0: if INFO = i, the algorithm failed to converge; i -* off-diagonal elements of an intermediate tridiagonal -* form did not converge to zero. -* * ===================================================================== * * .. Parameters .. |