2 den - denominator of a real number
13 For real x, den(x) returns the denominator of x when x is expressed
14 in lowest terms with positive denominator. In calc,
15 real values are actually rational values. Each calc real
16 value can be uniquely expressed as:
26 The denominator for this n/d is d.
29 > print den(7), den(-1.25), den(121/33)
36 NUMBER *qden(NUMBER *x)