
rationalize(+Number, -Result)
-Result is rationalize(+Number)

   Converts Number into a compact rational number and unifies it with Result.



Arguments
   Number              A number.
   Result              Output: rational number.

Type
   Arithmetic

Description

   Converts Number into a compact rational number and unifies it with Result.

   When Number is an integer, Result is a rational with denominator 1.

   When Number is already a rational, Result is identical to Number.

   When Number is a float, Result is a rational whose value approximates
   the value of the float to the accuracy of the float representation.
   rationalize/2 usually produces more compact rationals that rational/2.
   Both rationalize/2 and rational/2 produce results that convert back into
   the original float. rational/2 is usually faster than rationalize/2.

   Bounded reals cannot be converted to rationals.

   This predicate can be used as a function in arithmetic expressions.
   In coroutining mode, if Number is uninstantiated, the call to
   rationalize/2 is delayed until this variable is instantiated.


Modes and Determinism
   rationalize(+, -) is det

Exceptions
     4 --- Number is not instantiated (non-coroutining mode only).
    24 --- Number is not of a numeric type.
   141 --- Number is a bounded real

Examples
   
Success:
    Result is rationalize(25).		% gives Result = 25_1
    Result is rationalize(1.5).		% gives Result = 3_2
    Result is rationalize(3_4).		% gives Result = 3_4
    Result is rationalize(9_12).	% gives Result = 3_4
    Result is rationalize(-6).		% gives Result = -6_1
    Result is rationalize(0.1).		% gives Result = 1_10

Error:
    Result is rationalize(0.9__1.1).	% unimplemented


See Also
   rational / 2, is / 2
