ZHECON(l)		LAPACK routine (version	1.1)		    ZHECON(l)

NAME
  ZHECON - estimate the	reciprocal of the condition number of a	complex	Her-
  mitian matrix	A using	the factorization A = U*D*U**H or A = L*D*L**H com-
  puted	by ZHETRF

SYNOPSIS

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

      CHARACTER	     UPLO

      INTEGER	     INFO, LDA,	N

      DOUBLE	     PRECISION ANORM, RCOND

      INTEGER	     IPIV( * )

      COMPLEX*16     A(	LDA, * ), WORK(	* )

PURPOSE
  ZHECON estimates the reciprocal of the condition number of a complex Hermi-
  tian matrix A	using the factorization	A = U*D*U**H or	A = L*D*L**H computed
  by ZHETRF.

  An estimate is obtained for norm(inv(A)), and	the reciprocal of the condi-
  tion 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*16 array, dimension (LDA,N)
	  The block diagonal matrix D and the multipliers used to obtain the
	  factor U or L	as computed by ZHETRF.

  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 deter-
	  mined	by ZHETRF.

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

  RCOND	  (output) DOUBLE PRECISION
	  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*16 array,	dimension (2*N)

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


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