CPPCON  -  estimate the reciprocal of the condition number
       (in the 1-norm) of a complex Hermitian  positive  definite
       packed  matrix using the Cholesky factorization A = U**H*U
       or A = L*L**H computed by CPPTRF


SYNOPSIS

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

           CHARACTER      UPLO

           INTEGER        INFO, N

           REAL           ANORM, RCOND

           REAL           RWORK( * )

           COMPLEX        AP( * ), WORK( * )


PURPOSE

       CPPCON  estimates  the  reciprocal of the condition number
       (in the 1-norm) of a complex Hermitian  positive  definite
       packed  matrix using the Cholesky factorization A = U**H*U
       or A = L*L**H computed by CPPTRF.  An estimate is obtained
       for norm(inv(A)), and the reciprocal of the condition num­
       ber 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 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) REAL
               The 1-norm (or  infinity-norm)  of  the  Hermitian
               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


       WORK    (workspace) COMPLEX array, dimension (2*N)

       RWORK   (workspace) REAL array, dimension (N)

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


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