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dsyev.f(3)				      LAPACK				       dsyev.f(3)

NAME
       dsyev.f -

SYNOPSIS
   Functions/Subroutines
       subroutine dsyev (JOBZ, UPLO, N, A, LDA, W, WORK, LWORK, INFO)
	    DSYEV computes the eigenvalues and, optionally, the left and/or right eigenvectors
	   for SY matrices

Function/Subroutine Documentation
   subroutine dsyev (characterJOBZ, characterUPLO, integerN, double precision, dimension( lda, *
       )A, integerLDA, double precision, dimension( * )W, double precision, dimension( * )WORK,
       integerLWORK, integerINFO)
	DSYEV computes the eigenvalues and, optionally, the left and/or right eigenvectors for SY
       matrices

       Purpose:

	    DSYEV computes all eigenvalues and, optionally, eigenvectors of a
	    real symmetric matrix A.

       Parameters:
	   JOBZ

		     JOBZ is CHARACTER*1
		     = 'N':  Compute eigenvalues only;
		     = 'V':  Compute eigenvalues and eigenvectors.

	   UPLO

		     UPLO is CHARACTER*1
		     = 'U':  Upper triangle of A is stored;
		     = 'L':  Lower triangle of A is stored.

	   N

		     N is INTEGER
		     The order of the matrix A.  N >= 0.

	   A

		     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.

	   LDA

		     LDA is INTEGER
		     The leading dimension of the array A.  LDA >= max(1,N).

	   W

		     W is DOUBLE PRECISION array, dimension (N)
		     If INFO = 0, the eigenvalues in ascending order.

	   WORK

		     WORK is DOUBLE PRECISION array, dimension (MAX(1,LWORK))
		     On exit, if INFO = 0, WORK(1) returns the optimal LWORK.

	   LWORK

		     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.

		     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

		     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.

       Author:
	   Univ. of Tennessee

	   Univ. of California Berkeley

	   Univ. of Colorado Denver

	   NAG Ltd.

       Date:
	   November 2011

       Definition at line 133 of file dsyev.f.

Author
       Generated automatically by Doxygen for LAPACK from the source code.

Version 3.4.2				 Tue Sep 25 2012			       dsyev.f(3)
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