MATLAB Function Reference |

**Syntax**

**Description**

```
Y = atan(X)
```

returns the inverse tangent (arctangent) for each element of `X`

. For real elements of `X`

, `atan(X)`

is in the range .

The `atan`

function operates element-wise on arrays. The function's domains and ranges include complex values. All angles are in radians.

**Examples**

Graph the inverse tangent function over the domain .

**Definition**

The inverse tangent can be defined as

**Algorithm**

`atan`

uses FDLIBM, which was developed at SunSoft, a Sun Microsystems, Inc. business, by Kwok C. Ng, and others. For information about FDLIBM, see http://www.netlib.org.

**See Also**

assignin | atan2 |