CHEEV man page on Oracle

Man page or keyword search:  
man Server   33470 pages
apropos Keyword Search (all sections)
Output format
Oracle logo
[printable version]

cheev.f(3)			    LAPACK			    cheev.f(3)

       cheev.f -

       subroutine cheev (JOBZ, UPLO, N, A, LDA, W, WORK, LWORK, RWORK, INFO)
	    CHEEV computes the eigenvalues and, optionally, the left and/or
	   right eigenvectors for HE matrices

Function/Subroutine Documentation
   subroutine cheev (characterJOBZ, characterUPLO, integerN, complex,
       dimension( lda, * )A, integerLDA, real, dimension( * )W, complex,
       dimension( * )WORK, integerLWORK, real, dimension( * )RWORK,
	CHEEV computes the eigenvalues and, optionally, the left and/or right
       eigenvectors for HE matrices


	    CHEEV computes all eigenvalues and, optionally, eigenvectors of a
	    complex Hermitian matrix A.


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


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


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


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


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


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


		     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 CHETRD 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 is REAL array, dimension (max(1, 3*N-2))


		     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.

	   Univ. of Tennessee

	   Univ. of California Berkeley

	   Univ. of Colorado Denver

	   NAG Ltd.

	   November 2011

       Definition at line 140 of file cheev.f.

       Generated automatically by Doxygen for LAPACK from the source code.

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

List of man pages available for Oracle

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
Vote for polarhome
Free Shell Accounts :: the biggest list on the net