DPOCON man page on YellowDog

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

DPOCON(l)			       )			     DPOCON(l)

NAME
       DPOCON  -  estimate  the	 reciprocal  of	 the  condition number (in the
       1-norm) of a real symmetric positive definite matrix using the Cholesky
       factorization A = U**T*U or A = L*L**T computed by DPOTRF

SYNOPSIS
       SUBROUTINE DPOCON( UPLO, N, A, LDA, ANORM, RCOND, WORK, IWORK, INFO )

	   CHARACTER	  UPLO

	   INTEGER	  INFO, LDA, N

	   DOUBLE	  PRECISION ANORM, RCOND

	   INTEGER	  IWORK( * )

	   DOUBLE	  PRECISION A( LDA, * ), WORK( * )

PURPOSE
       DPOCON estimates the reciprocal of the condition number (in the 1-norm)
       of a real symmetric positive definite matrix using the Cholesky factor‐
       ization	A  =  U**T*U or A = L*L**T computed by DPOTRF.	An estimate is
       obtained for norm(inv(A)), and the reciprocal of the  condition	number
       is computed as RCOND = 1 / (ANORM * norm(inv(A))).

ARGUMENTS
       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.

       A       (input) DOUBLE PRECISION array, dimension (LDA,N)
	       The  triangular factor U or L from the Cholesky factorization A
	       = U**T*U or A = L*L**T, as computed by DPOTRF.

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

       ANORM   (input) DOUBLE PRECISION
	       The 1-norm (or infinity-norm) of the symmetric matrix A.

       RCOND   (output) DOUBLE PRECISION
	       The reciprocal of the condition number of the  matrix  A,  com‐
	       puted  as  RCOND = 1/(ANORM * AINVNM), where AINVNM is an esti‐
	       mate of the 1-norm of inv(A) computed in this routine.

       WORK    (workspace) DOUBLE PRECISION array, dimension (3*N)

       IWORK   (workspace) INTEGER array, dimension (N)

       INFO    (output) INTEGER
	       = 0:  successful exit
	       < 0:  if INFO = -i, the i-th argument had an illegal value

LAPACK version 3.0		 15 June 2000			     DPOCON(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