Inverse hyperbolic tangent

# atanh

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

atanh — Inverse hyperbolic tangent

### Descrierea

atanh ( float `$arg` ) : float

Returns the inverse hyperbolic tangent of `arg`, i.e. the value whose hyperbolic tangent is `arg`.

### Parametri

`arg`

  The argument to process

### Valorile întoarse

Inverse hyperbolic tangent of `arg`

### Istoricul schimbărilor

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

### A se vedea și

- tanh() - Hyperbolic tangent
- atan() - Arc tangent
- asinh() - Inverse hyperbolic sine
- acosh() - Inverse hyperbolic cosine