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gcd(+Number1, +Number2, -Result)

Unifies Results with the Greatest Common Divisor of Number1 and Number2
Number1
Integer.
Number2
Integer.
Result
A variable or integer.

Description

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

The Greatest Common Divisor operation is only defined on integer arguments.

In coroutining mode, if Number1 or Number2 are uninstantiated, the call is delayed until these variables are instantiated.

Modes and Determinism

Exceptions

(4) instantiation fault
Number1 or Number2 is not instantiated (non-coroutining mode only).
(5) type error
Result is a number but not an integer.
(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.
(24) number expected
Result is neither a number nor a variable.

Examples

Success:
      gcd(9, 15, 3).
      gcd(-9, 15, 3).
      gcd(2358352782,97895234896224,X).  ( gives X = 6 )

Error:
      gcd(A, 2, 6).             (Error 4).
      gcd(1, 2, 3.0).           (Error 5).
      gcd(1.0, 2, 3.0).         (Error 5).
      gcd(4 + 2, 2, 12).        (Error 24).

See Also

lcm / 3, is / 2