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CHECON(l)					)					CHECON(l)

NAME
       CHECON  -  estimate the reciprocal of the condition number of a complex Hermitian matrix A
       using the factorization A = U*D*U**H or A = L*D*L**H computed by CHETRF

SYNOPSIS
       SUBROUTINE CHECON( UPLO, N, A, LDA, IPIV, ANORM, RCOND, WORK, INFO )

	   CHARACTER	  UPLO

	   INTEGER	  INFO, LDA, N

	   REAL 	  ANORM, RCOND

	   INTEGER	  IPIV( * )

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

PURPOSE
       CHECON estimates the reciprocal of the condition number of a complex  Hermitian	matrix	A
       using  the  factorization A = U*D*U**H or A = L*D*L**H computed by CHETRF.  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
	       Specifies whether the details of the factorization are stored as an upper or lower
	       triangular matrix.  = 'U':  Upper triangular, form is A = U*D*U**H;
	       = 'L':  Lower triangular, form is A = L*D*L**H.

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

       A       (input) COMPLEX array, dimension (LDA,N)
	       The block diagonal matrix D and the multipliers used to obtain the factor U  or	L
	       as computed by CHETRF.

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

       IPIV    (input) INTEGER array, dimension (N)
	       Details of the interchanges and the block structure of D as determined by CHETRF.

       ANORM   (input) REAL
	       The 1-norm of the original matrix A.

       RCOND   (output) REAL
	       The  reciprocal	of  the  condition  number  of	the matrix A, computed as RCOND =
	       1/(ANORM * AINVNM), where AINVNM is an estimate of the 1-norm of  inv(A)  computed
	       in this routine.

       WORK    (workspace) COMPLEX 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 				CHECON(l)
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