ZGECON  -  estimate the reciprocal of the condition number
       of a general complex matrix A, in either the 1-norm or the
       infinity-norm,  using  the  LU  factorization  computed by
       ZGETRF


SYNOPSIS

       SUBROUTINE ZGECON( NORM, N, A, LDA,  ANORM,  RCOND,  WORK,
                          RWORK, INFO )

           CHARACTER      NORM

           INTEGER        INFO, LDA, N

           DOUBLE         PRECISION ANORM, RCOND

           DOUBLE         PRECISION RWORK( * )

           COMPLEX*16     A( LDA, * ), WORK( * )


PURPOSE

       ZGECON estimates the reciprocal of the condition number of
       a general complex matrix A, in either the  1-norm  or  the
       infinity-norm,  using  the  LU  factorization  computed by
       ZGETRF.  An estimate is obtained for norm(inv(A)), and 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.

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

       A       (input) COMPLEX*16 array, dimension (LDA,N)
               The factors L and U from  the  factorization  A  =
               P*L*U as computed by ZGETRF.

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

       ANORM   (input) DOUBLE PRECISION
               If NORM = '1' or 'O', the 1-norm of  the  original
               matrix A.  If NORM = 'I', the infinity-norm of the
               original matrix A.

       RCOND   (output) DOUBLE PRECISION
               The reciprocal of  the  condition  number  of  the

               norm(inv(A))).

       WORK    (workspace) COMPLEX*16 array, dimension (2*N)

       RWORK   (workspace) DOUBLE PRECISION array, dimension
               (2*N)

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


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