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<h1 id="function-atan2">Function atan2 <a href="#function-atan2" title="Permalink">#</a></h1>

Calculate the inverse tangent function with two arguments, y/x.
By providing two arguments, the right quadrant of the computed angle can be
determined.

For matrices, the function is evaluated element wise.


<h2 id="syntax">Syntax <a href="#syntax" title="Permalink">#</a></h2>

```js
math.atan2(y, x)
```

<h3 id="parameters">Parameters <a href="#parameters" title="Permalink">#</a></h3>

Parameter | Type | Description
--------- | ---- | -----------
`y` | number &#124; Array &#124; Matrix | Second dimension
`x` | number &#124; Array &#124; Matrix | First dimension

<h3 id="returns">Returns <a href="#returns" title="Permalink">#</a></h3>

Type | Description
---- | -----------
number &#124; Array &#124; Matrix | Four-quadrant inverse tangent


<h2 id="examples">Examples <a href="#examples" title="Permalink">#</a></h2>

```js
math.atan2(2, 2) / math.pi       // returns number 0.25

const angle = math.unit(60, 'deg') // returns Unit 60 deg
const x = math.cos(angle)
const y = math.sin(angle)

math.atan(2)             // returns Complex 1.5707963267948966 -1.3169578969248166 i
```


<h2 id="see-also">See also <a href="#see-also" title="Permalink">#</a></h2>

[tan](tan.html),
[atan](atan.html),
[sin](sin.html),
[cos](cos.html)