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authorjulie <julielangou@users.noreply.github.com>2011-10-06 06:53:11 +0000
committerjulie <julielangou@users.noreply.github.com>2011-10-06 06:53:11 +0000
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+*> \brief \b ZHEGST
+*
+* =========== DOCUMENTATION ===========
+*
+* Online html documentation available at
+* http://www.netlib.org/lapack/explore-html/
+*
+* Definition
+* ==========
+*
+* SUBROUTINE ZHEGV( ITYPE, JOBZ, UPLO, N, A, LDA, B, LDB, W, WORK,
+* LWORK, RWORK, INFO )
+*
+* .. Scalar Arguments ..
+* CHARACTER JOBZ, UPLO
+* INTEGER INFO, ITYPE, LDA, LDB, LWORK, N
+* ..
+* .. Array Arguments ..
+* DOUBLE PRECISION RWORK( * ), W( * )
+* COMPLEX*16 A( LDA, * ), B( LDB, * ), WORK( * )
+* ..
+*
+* Purpose
+* =======
+*
+*>\details \b Purpose:
+*>\verbatim
+*>
+*> ZHEGV computes all the eigenvalues, and optionally, the eigenvectors
+*> of a complex generalized Hermitian-definite eigenproblem, of the form
+*> A*x=(lambda)*B*x, A*Bx=(lambda)*x, or B*A*x=(lambda)*x.
+*> Here A and B are assumed to be Hermitian and B is also
+*> positive definite.
+*>
+*>\endverbatim
+*
+* Arguments
+* =========
+*
+*> \param[in] ITYPE
+*> \verbatim
+*> ITYPE is INTEGER
+*> Specifies the problem type to be solved:
+*> = 1: A*x = (lambda)*B*x
+*> = 2: A*B*x = (lambda)*x
+*> = 3: B*A*x = (lambda)*x
+*> \endverbatim
+*>
+*> \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 triangles of A and B are stored;
+*> = 'L': Lower triangles of A and B are stored.
+*> \endverbatim
+*>
+*> \param[in] N
+*> \verbatim
+*> N is INTEGER
+*> The order of the matrices A and B. 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.
+*> \endverbatim
+*> \verbatim
+*> On exit, if JOBZ = 'V', then if INFO = 0, A contains the
+*> matrix Z of eigenvectors. The eigenvectors are normalized
+*> as follows:
+*> if ITYPE = 1 or 2, Z**H*B*Z = I;
+*> if ITYPE = 3, Z**H*inv(B)*Z = I.
+*> If JOBZ = 'N', then on exit the upper triangle (if UPLO='U')
+*> or the lower triangle (if UPLO='L') 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[in,out] B
+*> \verbatim
+*> B is COMPLEX*16 array, dimension (LDB, N)
+*> On entry, the Hermitian positive definite matrix B.
+*> If UPLO = 'U', the leading N-by-N upper triangular part of B
+*> contains the upper triangular part of the matrix B.
+*> If UPLO = 'L', the leading N-by-N lower triangular part of B
+*> contains the lower triangular part of the matrix B.
+*> \endverbatim
+*> \verbatim
+*> On exit, if INFO <= N, the part of B containing the matrix is
+*> overwritten by the triangular factor U or L from the Cholesky
+*> factorization B = U**H*U or B = L*L**H.
+*> \endverbatim
+*>
+*> \param[in] LDB
+*> \verbatim
+*> LDB is INTEGER
+*> The leading dimension of the array B. LDB >= 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. LWORK >= max(1,2*N-1).
+*> For optimal efficiency, LWORK >= (NB+1)*N,
+*> where NB is the blocksize for ZHETRD 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] RWORK
+*> \verbatim
+*> RWORK is DOUBLE PRECISION array, dimension (max(1, 3*N-2))
+*> \endverbatim
+*>
+*> \param[out] INFO
+*> \verbatim
+*> INFO is INTEGER
+*> = 0: successful exit
+*> < 0: if INFO = -i, the i-th argument had an illegal value
+*> > 0: ZPOTRF or ZHEEV returned an error code:
+*> <= N: if INFO = i, ZHEEV failed to converge;
+*> i off-diagonal elements of an intermediate
+*> tridiagonal form did not converge to zero;
+*> > N: if INFO = N + i, for 1 <= i <= N, then the leading
+*> minor of order i of B is not positive definite.
+*> The factorization of B could not be completed and
+*> no eigenvalues or eigenvectors were computed.
+*> \endverbatim
+*>
+*
+* Authors
+* =======
+*
+*> \author Univ. of Tennessee
+*> \author Univ. of California Berkeley
+*> \author Univ. of Colorado Denver
+*> \author NAG Ltd.
+*
+*> \date November 2011
+*
+*> \ingroup complex16HEeigen
+*
+* =====================================================================
SUBROUTINE ZHEGV( ITYPE, JOBZ, UPLO, N, A, LDA, B, LDB, W, WORK,
$ LWORK, RWORK, INFO )
*
-* -- LAPACK driver routine (version 3.3.1) --
+* -- LAPACK eigen routine (version 3.3.1) --
* -- LAPACK is a software package provided by Univ. of Tennessee, --
* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
-* -- April 2011 --
+* November 2011
*
* .. Scalar Arguments ..
CHARACTER JOBZ, UPLO
@@ -15,98 +190,6 @@
COMPLEX*16 A( LDA, * ), B( LDB, * ), WORK( * )
* ..
*
-* Purpose
-* =======
-*
-* ZHEGV computes all the eigenvalues, and optionally, the eigenvectors
-* of a complex generalized Hermitian-definite eigenproblem, of the form
-* A*x=(lambda)*B*x, A*Bx=(lambda)*x, or B*A*x=(lambda)*x.
-* Here A and B are assumed to be Hermitian and B is also
-* positive definite.
-*
-* Arguments
-* =========
-*
-* ITYPE (input) INTEGER
-* Specifies the problem type to be solved:
-* = 1: A*x = (lambda)*B*x
-* = 2: A*B*x = (lambda)*x
-* = 3: B*A*x = (lambda)*x
-*
-* JOBZ (input) CHARACTER*1
-* = 'N': Compute eigenvalues only;
-* = 'V': Compute eigenvalues and eigenvectors.
-*
-* UPLO (input) CHARACTER*1
-* = 'U': Upper triangles of A and B are stored;
-* = 'L': Lower triangles of A and B are stored.
-*
-* N (input) INTEGER
-* The order of the matrices A and B. 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
-* matrix Z of eigenvectors. The eigenvectors are normalized
-* as follows:
-* if ITYPE = 1 or 2, Z**H*B*Z = I;
-* if ITYPE = 3, Z**H*inv(B)*Z = I.
-* If JOBZ = 'N', then on exit the upper triangle (if UPLO='U')
-* or the lower triangle (if UPLO='L') of A, including the
-* diagonal, is destroyed.
-*
-* LDA (input) INTEGER
-* The leading dimension of the array A. LDA >= max(1,N).
-*
-* B (input/output) COMPLEX*16 array, dimension (LDB, N)
-* On entry, the Hermitian positive definite matrix B.
-* If UPLO = 'U', the leading N-by-N upper triangular part of B
-* contains the upper triangular part of the matrix B.
-* If UPLO = 'L', the leading N-by-N lower triangular part of B
-* contains the lower triangular part of the matrix B.
-*
-* On exit, if INFO <= N, the part of B containing the matrix is
-* overwritten by the triangular factor U or L from the Cholesky
-* factorization B = U**H*U or B = L*L**H.
-*
-* LDB (input) INTEGER
-* The leading dimension of the array B. LDB >= 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. LWORK >= max(1,2*N-1).
-* For optimal efficiency, LWORK >= (NB+1)*N,
-* where NB is the blocksize for ZHETRD 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.
-*
-* RWORK (workspace) DOUBLE PRECISION array, dimension (max(1, 3*N-2))
-*
-* INFO (output) INTEGER
-* = 0: successful exit
-* < 0: if INFO = -i, the i-th argument had an illegal value
-* > 0: ZPOTRF or ZHEEV returned an error code:
-* <= N: if INFO = i, ZHEEV failed to converge;
-* i off-diagonal elements of an intermediate
-* tridiagonal form did not converge to zero;
-* > N: if INFO = N + i, for 1 <= i <= N, then the leading
-* minor of order i of B is not positive definite.
-* The factorization of B could not be completed and
-* no eigenvalues or eigenvectors were computed.
-*
* =====================================================================
*
* .. Parameters ..