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

Compute the argument of a complex value.
For a complex number `a + bi`, the argument is computed as `atan2(b, a)`.

For matrices, the function is evaluated element wise.


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

```js
math.arg(x)
```

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

Parameter | Type | Description
--------- | ---- | -----------
`x` | number &#124; BigNumber &#124; Complex &#124; Array &#124; Matrix |  A complex number or array with complex numbers

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

Type | Description
---- | -----------
number &#124; BigNumber &#124; Array &#124; Matrix | The argument of x


<h3 id="throws">Throws <a href="#throws" title="Permalink">#</a></h3>

Type | Description
---- | -----------


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

```js
const a = math.complex(2, 2)
math.arg(a) / math.pi          // returns number 0.25

const b = math.complex('2 + 3i')
math.arg(b)                    // returns number 0.982793723247329
math.atan2(3, 2)               // returns number 0.982793723247329
```


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

[re](re.html),
[im](im.html),
[conj](conj.html),
[abs](abs.html)