Returns numerator and denominator of normalized fraction.
DESCRIPTION
Given a rational number as supported by the Num library, numdom returns a
numerator-denominator pair corresponding to that rational number cancelled down
to its reduced form, $p/q$ where $q > 0$ and $p$ and $q$ have no common factor.
FAILURE CONDITIONS
Never fails.
EXAMPLE
# numdom(Int 22 // Int 7);;
val it : num * num = (22, 7)
# numdom(Int 0);;
val it : num * num = (0, 1)
# numdom(Int 100);;
val it : num * num = (100, 1)
# numdom(Int 4 // Int(-2));;
val it : num * num = (-2, 1)