The Math.atan()
function returns the arctangent (in radians) of a number, that is
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Syntax
Math.atan(x)
Parameters
- x
- A number.
Return value
The arctangent (in radians) of the given number.
Description
The Math.atan()
method returns a numeric value between and radians.
Because atan()
is a static method of Math
, you always use it as Math.atan()
, rather than as a method of a Math
object you created (Math
is not a constructor).
Examples
Using Math.atan()
Math.atan(1); // 0.7853981633974483
Math.atan(0); // 0
Math.atan(-0); // -0
Math.atan(Infinity); // 1.5707963267948966
Math.atan(-Infinity); // -1.5707963267948966
// The angle that the line [(0,0);(x,y)] forms with the x-axis in a Cartesian coordinate system
Math.atan(y / x);
Note that you may want to avoid using ±Infinity
for stylistic reasons. In this case, Math.atan2()
with 0
as the second argument may be a better solution.
Specifications
Specification |
---|
ECMAScript (ECMA-262) The definition of 'Math.atan' in that specification. |
Browser compatibility
The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Desktop | Mobile | Server | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
atan | Chrome Full support 1 | Edge Full support 12 | Firefox Full support 1 | IE Full support 3 | Opera Full support 3 | Safari Full support 1 | WebView Android Full support 1 | Chrome Android Full support 18 | Firefox Android Full support 4 | Opera Android Full support 10.1 | Safari iOS Full support 1 | Samsung Internet Android Full support 1.0 | nodejs Full support 0.1.100 |
Legend
- Full support
- Full support