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exp(+Number, ?Result)

Evaluates the exponential function exp(Number) ("e to the power of Number") and unifies the resulting value with Result.
+Number
A number.
?Result
A variable, float or breal.

Description

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

In coroutining mode, if Number is a free variable, the call to exp/2 is delayed until this variable is instantiated.

Fail Conditions

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

Resatisfiable

No

Exceptions

(4) instantiation fault
Number is not instantiated (non-coroutining mode only).
(5) type error
Result is a number but not a float or breal.
(24) number expected
Number is not of a numeric type.
(24) number expected
Result is neither a number nor a variable.
(20) arithmetic exception
floating point overflow

Examples

Success:
      exp(0.0, Result).       (gives Result = 1.0)
      exp(-6, Result).        (gives Result = 0.00247875)
Fail:
      exp(1, 0.0).
Error:
      exp(A, 6.0).                   (Error 4).
      exp(0, 1).                     (Error 5).
      exp(4 + 2, 403.429).           (Error 24).
      exp(1, r).                     (Error 24).

See Also

is / 2