ZPPCON(l)		LAPACK routine (version	1.1)		    ZPPCON(l)

NAME
  ZPPCON - estimate the	reciprocal of the condition number (in the 1-norm) of
  a complex Hermitian positive definite	packed matrix using the	Cholesky fac-
  torization A = U**H*U	or A = L*L**H computed by ZPPTRF

SYNOPSIS

  SUBROUTINE ZPPCON( UPLO, N, AP, ANORM, RCOND,	WORK, RWORK, INFO )

      CHARACTER	     UPLO

      INTEGER	     INFO, N

      DOUBLE	     PRECISION ANORM, RCOND

      DOUBLE	     PRECISION RWORK( *	)

      COMPLEX*16     AP( * ), WORK( * )

PURPOSE
  ZPPCON estimates the reciprocal of the condition number (in the 1-norm) of
  a complex Hermitian positive definite	packed matrix using the	Cholesky fac-
  torization A = U**H*U	or A = L*L**H computed by ZPPTRF.

  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
	  = '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.

  AP	  (input) COMPLEX*16 array, dimension (N*(N+1)/2)
	  The triangular factor	U or L from the	Cholesky factorization A =
	  U**H*U or A =	L*L**H,	packed columnwise in a linear array.  The j-
	  th column of U or L is stored	in the array AP	as follows: if UPLO =
	  'U', AP(i + (j-1)*j/2) = U(i,j) for 1<=i<=j; if UPLO = 'L', AP(i +
	  (j-1)*(2n-j)/2) = L(i,j) for j<=i<=n.

  ANORM	  (input) DOUBLE PRECISION
	  The 1-norm (or infinity-norm)	of the Hermitian 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)

  RWORK	  (workspace) DOUBLE PRECISION array, dimension	(N)

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

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