## TANH

The `TANH` function in ES|QL returns the Tangent hyperbolic function of an angle. The angle should be provided in radians. If the angle is null, the function will return null.

### Syntax

`TANH(angle)`

#### Parameters

- `angle`: An angle, in radians. If null, the function returns null.

### Examples

Here are a couple of examples of how to use the `TANH` function in ES|QL:

```esql
ROW a=1.8
| EVAL tanh = TANH(a)
```

In this example, the `TANH` function is used to calculate the Tangent hyperbolic function of the angle `1.8` radians.

```esql
ROW a=3.14
| EVAL tanh_result = TANH(a)
```

In this second example, the `TANH` function is used to calculate the Tangent hyperbolic function of the angle `3.14` radians. The result is stored in the `tanh_result` variable.