The **atanh()** function in R is **“used to calculate the inverse hyperbolic tangent of a number”**. For real numbers, **-1 < x < 1**. For complex numbers, the range is** -Inf < x < -1** and **1 < x < Inf**.

**Syntax**

`atanh(x)`

**Parameters**

**x:** It is a numeric value, array, or vector.

**Example 1: How to use the atanh() function**

`atanh(1)`

**Output**

`[1] Inf`

If you pass the 0 to the atanh() function, it will return 0.

`atanh(0)`

**Output**

`[1] 0`

**Example 2: Calculating atanh() of a complex number**

```
d <- 5 + 1i
atanh(d)
```

**Output**

`[1] 0.194426+1.530881i`

**Example 3: Using atanh() function to a Vector**

```
rv <- c(-1, 0.5, 0, 0.5, 1)
atanh(rv)
```

**Output**

`[1] -Inf 0.5493061 0.0000000 0.5493061 Inf`

**Example 4: Passing a pi to the atanh() function**

`atanh(pi)`

**Output**

```
[1] NaN
Warning message:
In atanh(pi) : NaNs produced
```

Let’s see another example of pi.

`atanh(pi / 4)`

**Output**

`[1] 1.059306`

**Plot the atanh() function to a graph**

We can use the seq() function to create a series of values and pass that to the plot() function, creating a line chart.

```
dt <- seq(-1, 1, by = 0.05)
plot(dt, atanh(dt), typ = "l", col = "red")
abline(v = 0, lty = 6, col = "blue")
```

**Output**

**Other Hyperbolic Trigonometric Functions**

The hyperbolic cosine of x (in radians).

The hyperbolic sine of x (in radians).

The hyperbolic tangent of x (in radians).

It is an inverse hyperbolic cosine (in radians).

It is an inverse hyperbolic cosine (in radians).

**R atanh(T x)**

It is an inverse hyperbolic tangent (in radians) of x.

That is it.

Krunal Lathiya is a Software Engineer with over eight years of experience. He has developed a strong foundation in computer science principles and a passion for problem-solving. In addition, Krunal has excellent knowledge of Data Science and Machine Learning, and he is an expert in R Language.