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Math.atan

The Math.atan() function returns the arctangent (in radians) of a number, that is

$$\mathtt{\operatorname{Math.atan}(x)} = \arctan(x) = \text{ the unique } \; y \in \left[-\frac{\pi}{2}; \frac{\pi}{2}\right] \, \text{such that} \; \tan(y) = x$$

Syntax

Math.atan(x)

Parameters

x

A number.

Description

The Math.atan() method returns a numeric value between $-\frac{\pi}{2}$ and $\frac{\pi}{2}$ 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

  Created by Mozilla Contributors, license: CC-BY-SA 2.5