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<h1 id="function-log2">Function log2 <a href="#function-log2" title="Permalink">#</a></h1>

Calculate the 2-base of a value. This is the same as calculating `log(x, 2)`.

For matrices, the function is evaluated element wise.


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

```js
math.log2(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 |  Value for which to calculate the logarithm.

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

Type | Description
---- | -----------
number &#124; BigNumber &#124; Complex &#124; Array &#124; Matrix |  Returns the 2-base logarithm 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
math.log2(0.03125)           // returns -5
math.log2(16)                // returns 4
math.log2(16) / math.log2(2) // returns 4
math.pow(2, 4)               // returns 16
```


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

[exp](exp.html),
[log](log.html),
[log1p](log1p.html),
[log10](log10.html)