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floor(+Number, ?Result)

Unifies Result with the greatest integral value that is less or equal than Number and of the same numeric type as Number.
+Number
A number.
?Result
A variable or number.

Description

This predicate is used by the ECLiPSe compiler to expand evaluable arithmetic expressions. So the call to floor(Number, Result) is equivalent to 
    Result is floor(Number)
which should be preferred for portability.

In coroutining mode, if Number is a free variable, the call to floor/2 is delayed until this variable is instantiated.

Fail Conditions

Fails if the result of the evaluation does not unify with Result.

Resatisfiable

No

Exceptions

(4) instantiation fault
Number is not instantiated (non-coroutining mode only).
(5) type error
Result and Number are numbers of different types.
(24) number expected
Number is not of a numeric type.
(24) number expected
Result is neither a number nor a variable.

Examples

Success:
      floor(1.8, 1.0).
      floor(-1.8, -2.0).
      floor(5, 5).
      floor(-6.4, Result).      (gives Result = -7.0)
Fail:
      floor(1.0, 0.0).
Error:
      floor(A, 6.0).                   (Error 4).
      floor(0.5, 0).                   (Error 5).
      floor(1, r).                     (Error 24).
      floor(4 + 2.3, 6.0).             (Error 24).

See Also

is / 2