SPPCON(l)		LAPACK routine (version	1.1)		    SPPCON(l)

NAME
  SPPCON - estimate the	reciprocal of the condition number (in the 1-norm) of
  a real symmetric positive definite packed matrix using the Cholesky factor-
  ization A = U**T*U or	A = L*L**T computed by SPPTRF

SYNOPSIS

  SUBROUTINE SPPCON( UPLO, N, AP, ANORM, RCOND,	WORK, IWORK, INFO )

      CHARACTER	     UPLO

      INTEGER	     INFO, N

      REAL	     ANORM, RCOND

      INTEGER	     IWORK( * )

      REAL	     AP( * ), WORK( * )

PURPOSE
  SPPCON estimates the reciprocal of the condition number (in the 1-norm) of
  a real symmetric positive definite packed matrix using the Cholesky factor-
  ization A = U**T*U or	A = L*L**T computed by SPPTRF.

  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) REAL array, dimension	(N*(N+1)/2)
	  The triangular factor	U or L from the	Cholesky factorization A =
	  U**T*U or A =	L*L**T,	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) REAL
	  The 1-norm (or infinity-norm)	of the symmetric matrix	A.

  RCOND	  (output) REAL
	  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) REAL 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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