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/(+Number1, +Number2, ?Result)

Evaluates the quotient Number1 / Number2 and unifies the resulting value with Result.
+Number1
A number.
+Number2
A number.
?Result
A variable or float (resp. rational).

Description

This predicate is used by the ECLiPSe compiler to expand evaluable arithmetic expressions. So the call to /(Number1, Number2, Result) is equivalent to 
    Result is Number1 / Number2
which should be preferred for portability.

The result type of the division depends on the value of the global flag prefer_rationals. When it is off, the result is a float, when it is on, the result is a rational. In coroutining mode, if Number1 or Number2 are free variables, the call to //3 is delayed until these variables are instantiated.

Fail Conditions

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

Resatisfiable

No

Exceptions

(4) instantiation fault
Number1 or Number2 is not instantiated (non-coroutining mode only).
(5) type error
Result is a number but not a float (resp. rational).
(24) number expected
Number1 or Number2 is not of a numeric type.
(24) number expected
Result is neither a number nor a variable.
(20) arithmetic exception
Illegal arithmetic operation: division by 0
(20) arithmetic exception
floating point overflow

Examples

Success:
    /(10, 2, 5.0).
    /(10, -2.0, -5.0).
    /(9, 12, 3_4).      (with set_flag(prefer_rationals, on))
Fail:
    /(1, 2, 1.0).
Error:
    /(A, 2, 6.0).            (Error 4).
    /(5, 2, r).              (Error 5).
    /(6, 2, 3).              (Error 5).
    /(2, 0, Result).         (Error 20).
    /(4 + 2, 2, 12).         (Error 24).

See Also

is / 2, get_flag / 2, set_flag / 2