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div(+Number1, +Number2, -Result)

Evaluates the integer quotient Number1 div Number2 and unifies the resulting value with Result.
A variable or integer.


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

This division operates on integer arguments, and delivers an integer result rounded down towards negative infinity (floored). The corresponding remainder is computed by the mod operation, such that the following equivalence always holds:

    X =:= (X mod Y) + (X div Y) * Y.

In coroutining mode, if Number1 or Number2 are uninstantiated, the call to (div)/3 is delayed until these variables are instantiated.

Modes and Determinism


(4) instantiation fault
Number1 or Number2 is not instantiated (non-coroutining mode only).
(5) type error
Number1 or Number2 is a number but not an integer.
(5) type error
Result is a number but not an integer.
(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


      X is 10 div 3.		( gives X = 3)

      div( 10,  3,  3).
      div(-10,  3, -4).
      div( 10, -3, -4).
      div(-10, -3,  3).
      div(1, 2, 3).
      div(A, 2, 6).              (Error 4).
      div(5, 2, r).              (Error 5).
      div(6, 2.0, 3.0).          (Error 5).
      div(2, 0, Result).        (Error 20).
      div(4 + 2, 2, 12).        (Error 24).

See Also

is / 2, // / 3, mod / 3