[ Arithmetic | The ECLiPSe Built-In Predicates | Reference Manual | Alphabetic Index ]

# float(+Number, -Result)

Converts Number to float and unifies the resulting value with Result.

Number
  A number.
Result
  A variable or float.

## Description

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

        Result is float(Number)

which should be preferred for portability.

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

### Modes and Determinism

- float(+, -) is det

### Exceptions

(4) instantiation fault
  Number is not instantiated (non-coroutining mode only).
(5) type error
  Result is a number but not a float.
(24) number expected
  Number is not of a numeric type.
(24) number expected
  Result is neither a number nor a variable.

## Examples

    Success:
          float(1, 1.0).
          float(-6, Result).         (gives Result = -6.0)
    Fail:
          float(1, 0.0).
    Error:
          float(A, 6.0).                   (Error 4).
          float(0, 0).                     (Error 5).
          float(4 + 2, 6.0).               (Error 24).
          float(1, r).                     (Error 24).

## See Also

is / 2