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

Create a new matrix or array with the results of a callback function executed on
each entry of a given matrix/array.

For each entry of the input, the callback is invoked with three arguments:
the value of the entry, the index at which that entry occurs, and the full
matrix/array being traversed. Note that because the matrix/array might be
multidimensional, the "index" argument is always an array of numbers giving
the index in each dimension. This is true even for vectors: the "index"
argument is an array of length 1, rather than simply a number.


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

```js
math.map(x, callback)
```

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

Parameter | Type | Description
--------- | ---- | -----------
`x` | Matrix &#124; Array | The input to iterate on.
`callback` | Function |  The function to call (as described above) on each entry of the input

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

Type | Description
---- | -----------
Matrix &#124; array |  Transformed map of x; always has the same type and shape as 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.map([1, 2, 3], function(value) {
  return value * value
})  // returns [1, 4, 9]

// The callback is normally called with three arguments:
//    callback(value, index, Array)
// If you want to call with only one argument, use:
math.map([1, 2, 3], x => math.format(x)) // returns ['1', '2', '3']
```


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

[filter](filter.html),
[forEach](forEach.html),
[sort](sort.html)