cgecon(l) [redhat man page]

CGECON(l)								 )								 CGECON(l)

NAME

       CGECON  -  estimate  the reciprocal of the condition number of a general complex matrix A, in either the 1-norm or the infinity-norm, using
       the LU factorization computed by CGETRF

SYNOPSIS

       SUBROUTINE CGECON( NORM, N, A, LDA, ANORM, RCOND, WORK, RWORK, INFO )

	   CHARACTER	  NORM

	   INTEGER	  INFO, LDA, N

	   REAL 	  ANORM, RCOND

	   REAL 	  RWORK( * )

	   COMPLEX	  A( LDA, * ), WORK( * )

PURPOSE

       CGECON estimates the reciprocal of the condition number of a general complex matrix A, in either the 1-norm or the infinity-norm, using the
       LU factorization computed by CGETRF.  An estimate is obtained for norm(inv(A)), and the reciprocal of the condition number is computed as
	  RCOND = 1 / ( norm(A) * norm(inv(A)) ).

ARGUMENTS

       NORM    (input) CHARACTER*1
	       Specifies whether the 1-norm condition number or the infinity-norm condition number is required:
	       = '1' or 'O':  1-norm;
	       = 'I':	      Infinity-norm.

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

       A       (input) COMPLEX array, dimension (LDA,N)
	       The factors L and U from the factorization A = P*L*U as computed by CGETRF.

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

       ANORM   (input) REAL
	       If NORM = '1' or 'O', the 1-norm of the original matrix A.  If NORM = 'I', the infinity-norm of the original matrix A.

       RCOND   (output) REAL
	       The reciprocal of the condition number of the matrix A, computed as RCOND = 1/(norm(A) * norm(inv(A))).

       WORK    (workspace) COMPLEX array, dimension (2*N)

       RWORK   (workspace) REAL array, dimension (2*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 							 CGECON(l)

cgecon.f(3)							      LAPACK							       cgecon.f(3)

NAME

       cgecon.f -

SYNOPSIS

   Functions/Subroutines
       subroutine cgecon (NORM, N, A, LDA, ANORM, RCOND, WORK, RWORK, INFO)
	   CGECON

Function/Subroutine Documentation
   subroutine cgecon (characterNORM, integerN, complex, dimension( lda, * )A, integerLDA, realANORM, realRCOND, complex, dimension( * )WORK, real,
       dimension( * )RWORK, integerINFO)
       CGECON

       Purpose:

	    CGECON estimates the reciprocal of the condition number of a general
	    complex matrix A, in either the 1-norm or the infinity-norm, using
	    the LU factorization computed by CGETRF.

	    An estimate is obtained for norm(inv(A)), and the reciprocal of the
	    condition number is computed as
	       RCOND = 1 / ( norm(A) * norm(inv(A)) ).

       Parameters:
	   NORM

		     NORM is CHARACTER*1
		     Specifies whether the 1-norm condition number or the
		     infinity-norm condition number is required:
		     = '1' or 'O':  1-norm;
		     = 'I':	    Infinity-norm.

	   N

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

	   A

		     A is COMPLEX array, dimension (LDA,N)
		     The factors L and U from the factorization A = P*L*U
		     as computed by CGETRF.

	   LDA

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

	   ANORM

		     ANORM is REAL
		     If NORM = '1' or 'O', the 1-norm of the original matrix A.
		     If NORM = 'I', the infinity-norm of the original matrix A.

	   RCOND

		     RCOND is REAL
		     The reciprocal of the condition number of the matrix A,
		     computed as RCOND = 1/(norm(A) * norm(inv(A))).

	   WORK

		     WORK is COMPLEX array, dimension (2*N)

	   RWORK

		     RWORK is REAL array, dimension (2*N)

	   INFO

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

       Author:
	   Univ. of Tennessee

	   Univ. of California Berkeley

	   Univ. of Colorado Denver

	   NAG Ltd.

       Date:
	   November 2011

       Definition at line 124 of file cgecon.f.

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

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