JavaScript atan2() Method
Example - atan2(y,x)
Assume you had a point with the (x,y) coordinates of (4,8), you could calculate the angle in radians between that point and the positive X axis as follows:
Math.atan2(8, 4);
Definition and Usage
The atan2() method returns the arctangent of the quotient of its arguments, as a numeric value between PI and -PI radians.
The number returned represents the counterclockwise angle in radians (not degrees) between the positive X axis and the point (x, y).
Note: With atan2(), the y coordinate is passed as the first argument and the x coordinate is passed as the second argument.
Browser Support
| Method | |||||
|---|---|---|---|---|---|
| atan2() | Yes | Yes | Yes | Yes | Yes |
Syntax
Math.atan2(y, x)
| Parameter | Description |
|---|---|
| y | Required. A number representing the y coordinate |
| x | Required. A number representing the x coordinate |
Technical Details
| Return Value: | A Number, from PI to -PI, or NaN if the value(s) are empty |
|---|---|
| JavaScript Version: | ECMAScript 1 |
