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# atan

## Description

example

Y = atan(X) returns the Inverse Tangent (tan-1) of the elements of X. The atan function operates element-wise on arrays. For real elements of X, atan(X) returns values in the interval [-pi/2,pi/2]. For complex values of X, atan(X) returns complex values. All angles are in radians.

## Examples

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### Inverse Tangent of a Value

`atan(0.8)`
```ans =
0.6747```

### Inverse Tangent of a Vector of Complex Values

Find the inverse tangent of the elements of vector x. The atan function acts on x element-wise.

```x = [0.5i 1+3i -2.2+i];
Y = atan(x)```
```Y =
0.0000 + 0.5493i   1.4615 + 0.3059i  -1.2019 + 0.1506i```

### Plot the Inverse Tangent Function

Plot the inverse tangent function over the interval .

```x = -20:0.01:20;
plot(x,atan(x))
grid on
```

## Input Arguments

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### X — Numeric inputnumber | vector | matrix | multidimensional array

Numeric input, specified as a number, vector, matrix, or multidimensional array.

Data Types: single | double
Complex Number Support: Yes

${\mathrm{tan}}^{-1}\left(z\right)=\frac{i}{2}\mathrm{log}\left(\frac{i+z}{i-z}\right).$