ZPBCON(l)		LAPACK routine (version	1.1)		    ZPBCON(l)

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

SYNOPSIS

  SUBROUTINE ZPBCON( UPLO, N, KD, AB, LDAB, ANORM, RCOND, WORK,	RWORK, INFO )

      CHARACTER	     UPLO

      INTEGER	     INFO, KD, LDAB, N

      DOUBLE	     PRECISION ANORM, RCOND

      DOUBLE	     PRECISION RWORK( *	)

      COMPLEX*16     AB( LDAB, * ), WORK( * )

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

  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	triangular factor stored in AB;
	  = 'L':  Lower	triangular factor stored in AB.

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

  KD	  (input) INTEGER
	  The number of	superdiagonals of the matrix A if UPLO = 'U', or the
	  number of sub-diagonals if UPLO = 'L'.  KD >=	0.

  AB	  (input) COMPLEX*16 array, dimension (LDAB,N)
	  The triangular factor	U or L from the	Cholesky factorization A =
	  U**H*U or A =	L*L**H of the band matrix A, stored in the first KD+1
	  rows of the array.  The j-th column of U or L	is stored in the
	  array	AB as follows: if UPLO ='U', AB(kd+1+i-j,j) = U(i,j) for
	  max(1,j-kd)<=i<=j; if	UPLO ='L', AB(1+i-j,j)	  = L(i,j) for
	  j<=i<=min(n,j+kd).

  LDAB	  (input) INTEGER
	  The leading dimension	of the array AB.  LDAB >= KD+1.

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