debian man page for zheev

zheev.f(3)							      LAPACK								zheev.f(3)

NAME
       zheev.f -

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

Function/Subroutine Documentation
   subroutine zheev (characterJOBZ, characterUPLO, integerN, complex*16, dimension( lda, * )A, integerLDA, double precision, dimension( * )W,
       complex*16, dimension( * )WORK, integerLWORK, double precision, dimension( * )RWORK, integerINFO)
	ZHEEV computes the eigenvalues and, optionally, the left and/or right eigenvectors for HE matrices

       Purpose:

	    ZHEEV computes all eigenvalues and, optionally, eigenvectors of a
	    complex Hermitian 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 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

		     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 COMPLEX*16 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(1,2*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

		     RWORK is DOUBLE PRECISION array, dimension (max(1, 3*N-2))

	   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 140 of file zheev.f.

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

Version 3.4.1							  Sun May 26 2013							zheev.f(3)