DTPCON(l)		LAPACK routine (version	1.1)		    DTPCON(l)

NAME
  DTPCON - estimate the	reciprocal of the condition number of a	packed tri-
  angular matrix A, in either the 1-norm or the	infinity-norm

SYNOPSIS

  SUBROUTINE DTPCON( NORM, UPLO, DIAG, N, AP, RCOND, WORK, IWORK, INFO )

      CHARACTER	     DIAG, NORM, UPLO

      INTEGER	     INFO, N

      DOUBLE	     PRECISION RCOND

      INTEGER	     IWORK( * )

      DOUBLE	     PRECISION AP( * ),	WORK( *	)

PURPOSE
  DTPCON estimates the reciprocal of the condition number of a packed tri-
  angular matrix A, in either the 1-norm or the	infinity-norm.

  The norm of A	is computed and	an estimate is obtained	for norm(inv(A)),
  then 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.

  UPLO	  (input) CHARACTER*1
	  = 'U':  A is upper triangular;
	  = 'L':  A is lower triangular.

  DIAG	  (input) CHARACTER*1
	  = 'N':  A is non-unit	triangular;
	  = 'U':  A is unit triangular.

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

  AP	  (input) DOUBLE PRECISION array, dimension (N*(N+1)/2)
	  The upper or lower triangular	matrix A, packed columnwise in a
	  linear array.	 The j-th column of A is stored	in the array AP	as
	  follows: if UPLO = 'U', AP(i + (j-1)*j/2) = A(i,j) for 1<=i<=j; if
	  UPLO = 'L', AP(i + (j-1)*(2n-j)/2) = A(i,j) for j<=i<=n.  If DIAG =
	  'U', the diagonal elements of	A are not referenced and are assumed
	  to be	1.

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

  WORK	  (workspace) DOUBLE PRECISION array, dimension	(3*N)

  IWORK	  (workspace) INTEGER 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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