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rational(?Rational)

Succeeds if Rational is a rational number.
Rational
Prolog term.

Description

Used to test whether Rational is a rational number.

Modes and Determinism

Fail Conditions

Fails if Rational is not a rational number

Examples

   Success:
   rational(1_3).
   set_flag(prefer_rationals, on), X is 1/3, rational(X).
   Fail:
   rational(1).
   rational(1.0).
   rational('1.0').
   rational(a).
   rational(X).

See Also

atomic / 1, integer / 1, number / 1, float / 1, real / 1, breal / 1