
getbit(+Number, +Index, ?Result)

   Result is the Index'th bit of Number.



Arguments
   +Number             Integer.
   +Index              Non-negative integer.
   ?Result             A variable or integer.

Type
   Arithmetic

Description
   Returns the Index'th bit of Number, assuming binary two's complement
   representation.  The least significant bit has index zero.
   The result is either 0 or 1.
   This predicate is used by the ECLiPSe compiler to expand evaluable
   arithmetic expressions.  So the call to getbit(Number, Index, Result) is
   equivalent to

    Result is getbit(Number, Index)

   which should be preferred.

   In coroutining mode, if Number or Index are free variables, the call
   is delayed until these variables are instantiated.




Resatisfiable
      No

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



Exceptions
     4 --- Number or Index is not instantiated (non-coroutining mode    only).
     5 --- Result is a number but not an integer.
     5 --- Number or Index is a number but not an integer.
    24 --- Number or Index is not of a numeric type.
    24 --- Result is neither a number nor a variable.

Examples
   
Success:
      getbit(10, 3, 1).
      getbit(10, 2, 0).
      getbit(10, 99, 0).





See Also
   is / 2, clrbit / 3, setbit / 3
