`nmono'
-------

nmono(RAT)
     :: Number of monomials in rational expression RAT.

RETURN
     non-negative integer

RAT
     rational expression

   * Number of monomials with non-zero number coefficients in the full
     expanded form of the given polynomial.

   * For a rational expression, the sum of the numbers of monomials of
     the numerator and denominator.

   * A function form is regarded as a single indeterminate no matter how
     complex arguments it has.

     [0] nmono((x+y)^10);
     11
     [1] nmono((x+y)^10/(x+z)^10);
     22
     [2] nmono(sin((x+y)^10));
     1

References
     *Note `vtype': vtype.

