number_abs
----------

number_abs(X)
     :

Example:

      number_abs(-3);

number_ceiling
--------------

number_ceiling(X)
     :

Example:

      number_abs(1.5);

number_floor
------------

number_floor(X)
     :

Example:

      number_floor(1.5);

number_imaginary_part
---------------------

number_imaginary_part(X)
     :

Example:

      number_imaginary_part(1+2*@i);

number_is_integer
-----------------

number_is_integer(X)
     :

Example:

      number_is_integer(2/3);

number_real_part
----------------

number_real_part(X)
     :

Example:

      number_real_part(1+2*@i);