# R - atanh() Function

The R atanh() function returns inverse hyperbolic tangent of a value. The inverse hyperbolic tangent of x is defined as: where e is an Euler's number.

In special cases it returns the following:

• If the argument is NaN, then the result is NaN.
• If the absolute value of argument is greater than 1, then the result is NaN.
• If the argument is 1 or -1, then the result is infinity with same sign as argument.

### Syntax

```atanh(x)
```

### Parameters

 `x` `Required. `Specify column to compute on.

### Return Value

Returns the inverse hyperbolic tangent of the value.

### Example:

In the example below, atanh() function is used to find out the inverse hyperbolic tangent of the value.

```#operating on single element atomic vector
print(atanh(-1))
print(atanh(0))
print(atanh(1))

cat("\nOperating on vector\n")
#operating on vector
v <- c(-0.5, 0, 0.5)
print(atanh(v))

cat("\nOperating on matrix\n")
#operating on matrix
m <- matrix(c(-0.5, -0.2, 0, 0.2, 0.5, NaN), nrow=2)
print(atanh(m))

cat("\nOperating on first column of matrix\n")
#operating on first column of matrix
print(atanh(m[,1]))
```

The output of the above code will be:

``` -Inf
 0
 Inf

Operating on vector
 -0.5493061  0.0000000  0.5493061

Operating on matrix
[,1]      [,2]      [,3]
[1,] -0.5493061 0.0000000 0.5493061
[2,] -0.2027326 0.2027326       NaN

Operating on first column of matrix
 -0.5493061 -0.2027326
```

❮ R Math Functions

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