DTRCON(l)		LAPACK routine (version	1.1)		    DTRCON(l)

NAME
  DTRCON - estimate the	reciprocal of the condition number of a	triangular
  matrix A, in either the 1-norm or the	infinity-norm

SYNOPSIS

  SUBROUTINE DTRCON( NORM, UPLO, DIAG, N, A, LDA, RCOND, WORK, IWORK, INFO )

      CHARACTER	     DIAG, NORM, UPLO

      INTEGER	     INFO, LDA,	N

      DOUBLE	     PRECISION RCOND

      INTEGER	     IWORK( * )

      DOUBLE	     PRECISION A( LDA, * ), WORK( * )

PURPOSE
  DTRCON estimates the reciprocal of the condition number of a triangular
  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.

  A	  (input) DOUBLE PRECISION array, dimension (LDA,N)
	  The triangular matrix	A.  If UPLO = 'U', the leading N-by-N upper
	  triangular part of the array A contains the upper triangular
	  matrix, and the strictly lower triangular part of A is not refer-
	  enced.  If UPLO = 'L', the leading N-by-N lower triangular part of
	  the array A contains the lower triangular matrix, and	the strictly
	  upper	triangular part	of A is	not referenced.	 If DIAG = 'U',	the
	  diagonal elements of A are also not referenced and are assumed to
	  be 1.

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

  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