
rationalize(+Number, -Result)

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



Arguments
   Number              A number.
   Result              Output: rational number.

Type
   Arithmetic

Description
   This predicate is used by the ECLiPSe compiler to expand evaluable
   arithmetic expressions.  So the call to rationalize(Number, Result) is
   equivalent to

    Result is rationalize(Number)

    which should be preferred.

   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.

   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
