Returns exp(number) - 1, computed in a way that is accurate even when the value of number is close to zero

# expm1

(PHP 4 >= 4.1.0, PHP 5, PHP 7)

expm1 — Returns exp(number) - 1, computed in a way that is accurate even when the value of number is close to zero

### Descrierea

expm1 ( float `$arg` ) : float

expm1() returns the equivalent to 'exp(`arg`) - 1' computed in a way that is accurate even if the value of `arg` is near zero, a case where 'exp (`arg`) - 1' would be inaccurate due to subtraction of two numbers that are nearly equal.

### Parametri

`arg`

  The argument to process

### Valorile întoarse

'e' to the power of `arg` minus one

### Istoricul schimbărilor

Versiune | Descriere
--- | ---
5.3.0 | This function is now available on all platforms

### A se vedea și

- log1p() - Returns log(1 + number), computed in a way that is accurate even when the value of number is close to zero
- exp() - Calculates the exponent of e