
sqrt(+Number, -Result)

   Evaluates the square root sqrt(Number) and unifies the resulting value with
Result.



Arguments
   Number              A number.
   Result              A variable, float or breal.

Type
   Arithmetic

Description
   This predicate is used by the ECLiPSe compiler to expand evaluable
   arithmetic expressions.  So the call to sqrt(Number, Result) is
   equivalent to

    Result is sqrt(Number)

    which should be preferred for portability.

   In coroutining mode, if Number is uninstantiated, the call to sqrt/2 is
   delayed until this variable is instantiated.




Modes and Determinism
   sqrt(+, -) is det

Exceptions
     4 --- Number is not instantiated (non-coroutining mode only).
     5 --- Result is a number but not a float or breal.
    24 --- Number is not of a numeric type.
    24 --- Result is neither a number nor a variable.
    20 --- Illegal arithmetic operation:  Number is negative.

Examples
   
Success:
      sqrt(1.0, 1.0).
      sqrt(1.0, Result).      (gives Result = 1.0)
      sqrt(49, Result).       (gives Result = 7.0)
Fail:
      sqrt(1, 0.0).
Error:
      sqrt(A, 6.0).                   (Error 4).
      sqrt(1, 1).                     (Error 5).
      sqrt(-2, Result).               (Error 20).
      sqrt(4 + 2, 2.44949).           (Error 24).
      sqrt(1, r).                     (Error 24).





See Also
   is / 2
