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# div(+Number1, +Number2, -Result)

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

Number1
  Integer.
Number2
  Integer.
Result
  Output: integer.

## Description

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.

The relationship with floating-point division is:

        X div Y =:= integer(floor(X/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

- div(+, +, -) is det

### Exceptions

(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.
(24) number expected
  Number1 or Number2 is not of a numeric type.
(20) arithmetic exception
  Illegal arithmetic operation: division by 0

## Examples

    Success:
        X is  10 div  3.		% gives X =  3
        X is -10 div  3.		% gives X = -4
        X is  10 div -3.		% gives X = -4
        X is -10 div -3.		% gives X =  3

    Error:
        X is 2 div 0.		% arithmetic exception

## See Also

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