chpev man page on YellowDog

Man page or keyword search:  
man Server   18644 pages
apropos Keyword Search (all sections)
Output format
YellowDog logo
[printable version]

CHPEV(l)			       )			      CHPEV(l)

NAME
       CHPEV  - compute all the eigenvalues and, optionally, eigenvectors of a
       complex Hermitian matrix in packed storage

SYNOPSIS
       SUBROUTINE CHPEV( JOBZ, UPLO, N, AP, W, Z, LDZ, WORK, RWORK, INFO )

	   CHARACTER	 JOBZ, UPLO

	   INTEGER	 INFO, LDZ, N

	   REAL		 RWORK( * ), W( * )

	   COMPLEX	 AP( * ), WORK( * ), Z( LDZ, * )

PURPOSE
       CHPEV computes all the eigenvalues and, optionally, eigenvectors	 of  a
       complex Hermitian matrix in packed storage.

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.

       AP      (input/output) COMPLEX array, dimension (N*(N+1)/2)
	       On  entry,  the upper or lower triangle of the Hermitian matrix
	       A, packed columnwise in a linear array.	The j-th column	 of  A
	       is  stored  in  the  array AP as follows: if UPLO = 'U', AP(i +
	       (j-1)*j/2) =  A(i,j)  for  1<=i<=j;  if	UPLO  =	 'L',  AP(i  +
	       (j-1)*(2*n-j)/2) = A(i,j) for j<=i<=n.

	       On  exit,  AP  is  overwritten  by  values generated during the
	       reduction to tridiagonal form.  If UPLO = 'U', the diagonal and
	       first  superdiagonal  of the tridiagonal matrix T overwrite the
	       corresponding elements of A, and if UPLO =  'L',	 the  diagonal
	       and first subdiagonal of T overwrite the corresponding elements
	       of A.

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

       Z       (output) COMPLEX array, dimension (LDZ, N)
	       If JOBZ = 'V', then if INFO = 0,	 Z  contains  the  orthonormal
	       eigenvectors of the matrix A, with the i-th column of Z holding
	       the eigenvector associated with W(i).  If JOBZ = 'N', then Z is
	       not referenced.

       LDZ     (input) INTEGER
	       The  leading dimension of the array Z.  LDZ >= 1, and if JOBZ =
	       'V', LDZ >= max(1,N).

       WORK    (workspace) COMPLEX array, dimension (max(1, 2*N-1))

       RWORK   (workspace) REAL 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:  if INFO = i, the algorithm failed	to  converge;  i  off-
	       diagonal	 elements  of an intermediate tridiagonal form did not
	       converge to zero.

LAPACK version 3.0		 15 June 2000			      CHPEV(l)
[top]

List of man pages available for YellowDog

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]
Tweet
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