--- rpl/lapack/lapack/zheevd.f 2010/01/26 15:22:45 1.1
+++ rpl/lapack/lapack/zheevd.f 2023/08/07 08:39:23 1.17
@@ -1,10 +1,211 @@
+*> \brief ZHEEVD computes the eigenvalues and, optionally, the left and/or right eigenvectors for HE matrices
+*
+* =========== DOCUMENTATION ===========
+*
+* Online html documentation available at
+* http://www.netlib.org/lapack/explore-html/
+*
+*> \htmlonly
+*> Download ZHEEVD + dependencies
+*>
+*> [TGZ]
+*>
+*> [ZIP]
+*>
+*> [TXT]
+*> \endhtmlonly
+*
+* Definition:
+* ===========
+*
+* SUBROUTINE ZHEEVD( JOBZ, UPLO, N, A, LDA, W, WORK, LWORK, RWORK,
+* LRWORK, IWORK, LIWORK, INFO )
+*
+* .. Scalar Arguments ..
+* CHARACTER JOBZ, UPLO
+* INTEGER INFO, LDA, LIWORK, LRWORK, LWORK, N
+* ..
+* .. Array Arguments ..
+* INTEGER IWORK( * )
+* DOUBLE PRECISION RWORK( * ), W( * )
+* COMPLEX*16 A( LDA, * ), WORK( * )
+* ..
+*
+*
+*> \par Purpose:
+* =============
+*>
+*> \verbatim
+*>
+*> ZHEEVD computes all eigenvalues and, optionally, eigenvectors of a
+*> complex Hermitian matrix A. If eigenvectors are desired, it uses a
+*> divide and conquer algorithm.
+*>
+*> The divide and conquer algorithm makes very mild assumptions about
+*> floating point arithmetic. It will work on machines with a guard
+*> digit in add/subtract, or on those binary machines without guard
+*> digits which subtract like the Cray X-MP, Cray Y-MP, Cray C-90, or
+*> Cray-2. It could conceivably fail on hexadecimal or decimal machines
+*> without guard digits, but we know of none.
+*> \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 COMPLEX*16 array, dimension (LDA, N)
+*> On entry, the Hermitian 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 COMPLEX*16 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.
+*> If N <= 1, LWORK must be at least 1.
+*> If JOBZ = 'N' and N > 1, LWORK must be at least N + 1.
+*> If JOBZ = 'V' and N > 1, LWORK must be at least 2*N + N**2.
+*>
+*> If LWORK = -1, then a workspace query is assumed; the routine
+*> only calculates the optimal sizes of the WORK, RWORK and
+*> IWORK arrays, returns these values as the first entries of
+*> the WORK, RWORK and IWORK arrays, and no error message
+*> related to LWORK or LRWORK or LIWORK is issued by XERBLA.
+*> \endverbatim
+*>
+*> \param[out] RWORK
+*> \verbatim
+*> RWORK is DOUBLE PRECISION array,
+*> dimension (LRWORK)
+*> On exit, if INFO = 0, RWORK(1) returns the optimal LRWORK.
+*> \endverbatim
+*>
+*> \param[in] LRWORK
+*> \verbatim
+*> LRWORK is INTEGER
+*> The dimension of the array RWORK.
+*> If N <= 1, LRWORK must be at least 1.
+*> If JOBZ = 'N' and N > 1, LRWORK must be at least N.
+*> If JOBZ = 'V' and N > 1, LRWORK must be at least
+*> 1 + 5*N + 2*N**2.
+*>
+*> If LRWORK = -1, then a workspace query is assumed; the
+*> routine only calculates the optimal sizes of the WORK, RWORK
+*> and IWORK arrays, returns these values as the first entries
+*> of the WORK, RWORK and IWORK arrays, and no error message
+*> related to LWORK or LRWORK or LIWORK is issued by XERBLA.
+*> \endverbatim
+*>
+*> \param[out] IWORK
+*> \verbatim
+*> IWORK is INTEGER array, dimension (MAX(1,LIWORK))
+*> On exit, if INFO = 0, IWORK(1) returns the optimal LIWORK.
+*> \endverbatim
+*>
+*> \param[in] LIWORK
+*> \verbatim
+*> LIWORK is INTEGER
+*> The dimension of the array IWORK.
+*> If N <= 1, LIWORK must be at least 1.
+*> If JOBZ = 'N' and N > 1, LIWORK must be at least 1.
+*> If JOBZ = 'V' and N > 1, LIWORK must be at least 3 + 5*N.
+*>
+*> If LIWORK = -1, then a workspace query is assumed; the
+*> routine only calculates the optimal sizes of the WORK, RWORK
+*> and IWORK arrays, returns these values as the first entries
+*> of the WORK, RWORK and IWORK arrays, and no error message
+*> related to LWORK or LRWORK or LIWORK 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 and JOBZ = 'N', then the algorithm failed
+*> to converge; i off-diagonal elements of an intermediate
+*> tridiagonal form did not converge to zero;
+*> if INFO = i and JOBZ = 'V', then the algorithm failed
+*> to compute an eigenvalue while working on the submatrix
+*> lying in rows and columns INFO/(N+1) through
+*> mod(INFO,N+1).
+*> \endverbatim
+*
+* Authors:
+* ========
+*
+*> \author Univ. of Tennessee
+*> \author Univ. of California Berkeley
+*> \author Univ. of Colorado Denver
+*> \author NAG Ltd.
+*
+*> \ingroup complex16HEeigen
+*
+*> \par Further Details:
+* =====================
+*>
+*> Modified description of INFO. Sven, 16 Feb 05.
+*
+*> \par Contributors:
+* ==================
+*>
+*> Jeff Rutter, Computer Science Division, University of California
+*> at Berkeley, USA
+*>
+* =====================================================================
SUBROUTINE ZHEEVD( JOBZ, UPLO, N, A, LDA, W, WORK, LWORK, RWORK,
$ LRWORK, IWORK, LIWORK, INFO )
*
-* -- LAPACK driver routine (version 3.2) --
+* -- LAPACK driver routine --
* -- LAPACK is a software package provided by Univ. of Tennessee, --
* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
-* November 2006
*
* .. Scalar Arguments ..
CHARACTER JOBZ, UPLO
@@ -16,118 +217,6 @@
COMPLEX*16 A( LDA, * ), WORK( * )
* ..
*
-* Purpose
-* =======
-*
-* ZHEEVD computes all eigenvalues and, optionally, eigenvectors of a
-* complex Hermitian matrix A. If eigenvectors are desired, it uses a
-* divide and conquer algorithm.
-*
-* The divide and conquer algorithm makes very mild assumptions about
-* floating point arithmetic. It will work on machines with a guard
-* digit in add/subtract, or on those binary machines without guard
-* digits which subtract like the Cray X-MP, Cray Y-MP, Cray C-90, or
-* Cray-2. It could conceivably fail on hexadecimal or decimal machines
-* without guard digits, but we know of none.
-*
-* 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) COMPLEX*16 array, dimension (LDA, N)
-* On entry, the Hermitian 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) COMPLEX*16 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.
-* If N <= 1, LWORK must be at least 1.
-* If JOBZ = 'N' and N > 1, LWORK must be at least N + 1.
-* If JOBZ = 'V' and N > 1, LWORK must be at least 2*N + N**2.
-*
-* If LWORK = -1, then a workspace query is assumed; the routine
-* only calculates the optimal sizes of the WORK, RWORK and
-* IWORK arrays, returns these values as the first entries of
-* the WORK, RWORK and IWORK arrays, and no error message
-* related to LWORK or LRWORK or LIWORK is issued by XERBLA.
-*
-* RWORK (workspace/output) DOUBLE PRECISION array,
-* dimension (LRWORK)
-* On exit, if INFO = 0, RWORK(1) returns the optimal LRWORK.
-*
-* LRWORK (input) INTEGER
-* The dimension of the array RWORK.
-* If N <= 1, LRWORK must be at least 1.
-* If JOBZ = 'N' and N > 1, LRWORK must be at least N.
-* If JOBZ = 'V' and N > 1, LRWORK must be at least
-* 1 + 5*N + 2*N**2.
-*
-* If LRWORK = -1, then a workspace query is assumed; the
-* routine only calculates the optimal sizes of the WORK, RWORK
-* and IWORK arrays, returns these values as the first entries
-* of the WORK, RWORK and IWORK arrays, and no error message
-* related to LWORK or LRWORK or LIWORK is issued by XERBLA.
-*
-* IWORK (workspace/output) INTEGER array, dimension (MAX(1,LIWORK))
-* On exit, if INFO = 0, IWORK(1) returns the optimal LIWORK.
-*
-* LIWORK (input) INTEGER
-* The dimension of the array IWORK.
-* If N <= 1, LIWORK must be at least 1.
-* If JOBZ = 'N' and N > 1, LIWORK must be at least 1.
-* If JOBZ = 'V' and N > 1, LIWORK must be at least 3 + 5*N.
-*
-* If LIWORK = -1, then a workspace query is assumed; the
-* routine only calculates the optimal sizes of the WORK, RWORK
-* and IWORK arrays, returns these values as the first entries
-* of the WORK, RWORK and IWORK arrays, and no error message
-* related to LWORK or LRWORK or LIWORK 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 and JOBZ = 'N', then the algorithm failed
-* to converge; i off-diagonal elements of an intermediate
-* tridiagonal form did not converge to zero;
-* if INFO = i and JOBZ = 'V', then the algorithm failed
-* to compute an eigenvalue while working on the submatrix
-* lying in rows and columns INFO/(N+1) through
-* mod(INFO,N+1).
-*
-* Further Details
-* ===============
-*
-* Based on contributions by
-* Jeff Rutter, Computer Science Division, University of California
-* at Berkeley, USA
-*
-* Modified description of INFO. Sven, 16 Feb 05.
* =====================================================================
*
* .. Parameters ..
@@ -195,7 +284,7 @@
LIWMIN = 1
END IF
LOPT = MAX( LWMIN, N +
- $ ILAENV( 1, 'ZHETRD', UPLO, N, -1, -1, -1 ) )
+ $ N*ILAENV( 1, 'ZHETRD', UPLO, N, -1, -1, -1 ) )
LROPT = LRWMIN
LIOPT = LIWMIN
END IF
@@ -225,7 +314,7 @@
$ RETURN
*
IF( N.EQ.1 ) THEN
- W( 1 ) = A( 1, 1 )
+ W( 1 ) = DBLE( A( 1, 1 ) )
IF( WANTZ )
$ A( 1, 1 ) = CONE
RETURN