# JavaScript - Math.atan2() Method

The JavaScript Math.atan2() method returns the angle theta from the conversion of rectangular coordinates (x, y) to polar coordinates (r, theta). The returned value will be in the range -𝜋 through 𝜋.

### Syntax

```Math.atan2(y, x)
```

### Parameters

 `y` Specify the ordinate coordinate. `x` Specify the abscissa coordinate.

### Return Value

Returns theta of the point (r, theta) in polar coordinates that corresponds to the point (x, y) in Cartesian coordinates.

### Example:

In the example below, Math.atan2() method is used to calculate the theta of a point.

```var txt;

txt = "Math.atan2(10, 10) = " + Math.atan2(10, 10) + "<br>";
txt = txt + "Math.atan2(20, 10) = " + Math.atan2(20, 10) + "<br>";
txt = txt + "Math.atan2(-20, 10) = " + Math.atan2(-20, 10) + "<br>";
```

The output (value of txt) after running above script will be:

```Math.atan2(10, 10) = 0.7853981633974483
Math.atan2(20, 10) = 1.1071487177940904
Math.atan2(-20, 10) = -1.1071487177940904
```

❮ JavaScript - Math Object

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