cheevd man page on OpenIndiana

Man page or keyword search:  
man Server   20441 pages
apropos Keyword Search (all sections)
Output format
OpenIndiana logo
[printable version]

cheevd(3P)		    Sun Performance Library		    cheevd(3P)

NAME
       cheevd  -  compute  all	eigenvalues and, optionally, eigenvectors of a
       complex Hermitian matrix A

SYNOPSIS
       SUBROUTINE CHEEVD(JOBZ, UPLO, N, A, LDA, W, WORK, LWORK, RWORK,
	     LRWORK, IWORK, LIWORK, INFO)

       CHARACTER * 1 JOBZ, UPLO
       COMPLEX A(LDA,*), WORK(*)
       INTEGER N, LDA, LWORK, LRWORK, LIWORK, INFO
       INTEGER IWORK(*)
       REAL W(*), RWORK(*)

       SUBROUTINE CHEEVD_64(JOBZ, UPLO, N, A, LDA, W, WORK, LWORK, RWORK,
	     LRWORK, IWORK, LIWORK, INFO)

       CHARACTER * 1 JOBZ, UPLO
       COMPLEX A(LDA,*), WORK(*)
       INTEGER*8 N, LDA, LWORK, LRWORK, LIWORK, INFO
       INTEGER*8 IWORK(*)
       REAL W(*), RWORK(*)

   F95 INTERFACE
       SUBROUTINE HEEVD(JOBZ, UPLO, [N], A, [LDA], W, [WORK], [LWORK],
	      [RWORK], [LRWORK], [IWORK], [LIWORK], [INFO])

       CHARACTER(LEN=1) :: JOBZ, UPLO
       COMPLEX, DIMENSION(:) :: WORK
       COMPLEX, DIMENSION(:,:) :: A
       INTEGER :: N, LDA, LWORK, LRWORK, LIWORK, INFO
       INTEGER, DIMENSION(:) :: IWORK
       REAL, DIMENSION(:) :: W, RWORK

       SUBROUTINE HEEVD_64(JOBZ, UPLO, [N], A, [LDA], W, [WORK], [LWORK],
	      [RWORK], [LRWORK], [IWORK], [LIWORK], [INFO])

       CHARACTER(LEN=1) :: JOBZ, UPLO
       COMPLEX, DIMENSION(:) :: WORK
       COMPLEX, DIMENSION(:,:) :: A
       INTEGER(8) :: N, LDA, LWORK, LRWORK, LIWORK, INFO
       INTEGER(8), DIMENSION(:) :: IWORK
       REAL, DIMENSION(:) :: W, RWORK

   C INTERFACE
       #include <sunperf.h>

       void cheevd(char jobz, char uplo, int n, complex *a, int lda, float *w,
		 int *info);

       void  cheevd_64(char  jobz,  char  uplo,	 long n, complex *a, long lda,
		 float *w, long *info);

PURPOSE
       cheevd computes all eigenvalues and, optionally, eigenvectors of a com‐
       plex Hermitian matrix A.	 If eigenvectors are desired, it uses a divide
       and conquer algorithm.

       The divide and conquer algorithm	 makes	very  mild  assumptions	 about
       floating	 point arithmetic. It will work on machines with a guard digit
       in add/subtract, or on those binary machines without guard digits which
       subtract	 like the Cray X-MP, Cray Y-MP, Cray C-90, or Cray-2. It could
       conceivably fail on hexadecimal or decimal machines without guard  dig‐
       its, but we know of none.

ARGUMENTS
       JOBZ (input)
		 = 'N':	 Compute eigenvalues only;
		 = 'V':	 Compute eigenvalues and eigenvectors.

       UPLO (input)
		 = 'U':	 Upper triangle of A is stored;
		 = 'L':	 Lower triangle of A is stored.

       N (input) The order of the matrix A.  N >= 0.

       A (input/output)
		 On entry, the Hermitian matrix A.  If UPLO = 'U', the leading
		 N-by-N upper triangular part of A contains the upper triangu‐
		 lar  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	diago‐
		 nal, is destroyed.

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

       W (output)
		 If INFO = 0, the eigenvalues in ascending order.

       WORK (workspace)
		 On exit, if INFO = 0, WORK(1) returns the optimal LWORK.

       LWORK (input)
		 The	length	  of   the   array   WORK.    If   N   <=   1,
		 LWORK must be at least 1.  If JOBZ  = 'N' and N  >  1,	 LWORK
		 must be at least N + 1.  If JOBZ  = 'V' and N > 1, LWORK must
		 be at least 2*N + N**2.

		 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)
		 dimension (LRWORK) On exit, if INFO = 0, RWORK(1) returns the
		 optimal LRWORK.

       LRWORK (input)
		 The  dimension	 of   the   array   RWORK.    If   N   <=   1,
		 LRWORK	 must be at least 1.  If JOBZ  = 'N' and N > 1, LRWORK
		 must be at least N.  If JOBZ  = 'V' and N > 1, LRWORK must be
		 at least 1 + 5*N + 2*N**2.

		 If  LRWORK  = -1, then a workspace query is assumed; the rou‐
		 tine only calculates the optimal size	of  the	 RWORK	array,
		 returns this value as the first entry of the RWORK array, and
		 no error message related to LRWORK is issued by XERBLA.

       IWORK (workspace/output)
		 On exit, if INFO = 0, IWORK(1) returns the optimal LIWORK.

       LIWORK (input)
		 The  dimension	 of   the   array   IWORK.    If   N   <=   1,
		 LIWORK	 must be at least 1.  If JOBZ  = 'N' and N > 1, LIWORK
		 must be at least 1.  If JOBZ  = 'V' and N > 1, LIWORK must be
		 at least 3 + 5*N.

		 If  LIWORK  = -1, then a workspace query is assumed; the rou‐
		 tine only calculates the optimal size	of  the	 IWORK	array,
		 returns this value as the first entry of the IWORK array, and
		 no error message related to LIWORK is issued by XERBLA.

       INFO (output)
		 = 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.

FURTHER DETAILS
       Based on contributions by
	  Jeff Rutter, Computer Science Division, University of California
	  at Berkeley, USA

				  6 Mar 2009			    cheevd(3P)
[top]

List of man pages available for OpenIndiana

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