recision (see LAPACK Library routine DLAMCH).
          The approximate symmetric chordal metric is used as
          "distance" of two complex, possibly infinite numbers, x
          and y. This metric is given by the formula

            d(x,y) = min( |x-y|, |1/x-1/y| ),

          taking into account the special cases of infinite or NaN
          values.
          If SORT = 'N' or 'C', this parameter is not referenced.

</PRE>
<B>Workspace</B>
<PRE>
  IWORK   INTEGER array, dimension (N+2)

</PRE>
<B>Err