151 lines
3.4 KiB
Markdown
151 lines
3.4 KiB
Markdown
<!--
|
|
|
|
@license Apache-2.0
|
|
|
|
Copyright (c) 2018 The Stdlib Authors.
|
|
|
|
Licensed under the Apache License, Version 2.0 (the "License");
|
|
you may not use this file except in compliance with the License.
|
|
You may obtain a copy of the License at
|
|
|
|
http://www.apache.org/licenses/LICENSE-2.0
|
|
|
|
Unless required by applicable law or agreed to in writing, software
|
|
distributed under the License is distributed on an "AS IS" BASIS,
|
|
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
See the License for the specific language governing permissions and
|
|
limitations under the License.
|
|
|
|
-->
|
|
|
|
# Zip
|
|
|
|
> Generate array tuples from input arrays.
|
|
|
|
<section class="intro">
|
|
|
|
</section>
|
|
|
|
<!-- /.intro -->
|
|
|
|
<section class="usage">
|
|
|
|
## Usage
|
|
|
|
```javascript
|
|
var zip = require( '@stdlib/utils/zip' );
|
|
```
|
|
|
|
#### zip( arr1, arr2,...\[, opts] )
|
|
|
|
Returns an `array` of `arrays`, where the ith element (tuple) in the returned `array` contains the ith elements of the input `arrays`.
|
|
|
|
```javascript
|
|
var zipped = zip( [ 1, 2 ], [ 'a', 'b' ] );
|
|
// returns [ [ 1, 'a' ], [ 2, 'b' ] ]
|
|
```
|
|
|
|
By default, the returned `array` length is the length of the shortest input `array`.
|
|
|
|
```javascript
|
|
var zipped = zip( [ 1, 2, 3 ], [ 'a', 'b' ] );
|
|
// returns [ [ 1, 'a' ], [ 2, 'b' ] ]
|
|
```
|
|
|
|
The function accepts an `options` object with optional properties:
|
|
|
|
- **trunc**: `boolean` specifying whether the returned `array` should truncate `arrays` longer than the shortest `array`. Default: `true`.
|
|
- **fill**: fill value used for unequal length `arrays`. Default: `null`.
|
|
- **arrays**: `boolean` specifying whether, when provided a single input `array`, the function should interpret the argument as a list of `arrays` to be zipped (i.e., behavior similar to `zip.apply(null, arr)`). Default: `false`.
|
|
|
|
To turn off truncation,
|
|
|
|
```javascript
|
|
var opts = {
|
|
'trunc': false
|
|
};
|
|
|
|
var zipped = zip( [ 1, 2, 3 ], [ 'a', 'b' ], opts );
|
|
// returns [ [ 1, 'a' ], [ 2, 'b' ], [ 3, null ] ]
|
|
```
|
|
|
|
A fill value is included in each tuple for each `array` which does not have an element at the ith index. By default, the fill value is `null`. To specify a different fill value, set the `fill` option.
|
|
|
|
```javascript
|
|
var opts = {
|
|
'trunc': false,
|
|
'fill': ''
|
|
};
|
|
|
|
var zipped = zip( [ 1, 2, 3 ], [ 'a', 'b' ], opts );
|
|
// returns [ [ 1, 'a' ], [ 2, 'b' ], [ 3, '' ] ]
|
|
```
|
|
|
|
If the function should interpret a single input `array` as an `array` of `arrays` to be zipped,
|
|
|
|
<!-- eslint-disable object-curly-newline -->
|
|
|
|
```javascript
|
|
var zipped;
|
|
var arr = [ [ 1, 2 ], [ 'a', 'b' ] ];
|
|
|
|
// Default behavior:
|
|
zipped = zip( arr );
|
|
// returns [ [ [ 1, 2 ] ], [ [ 'a', 'b' ] ] ]
|
|
|
|
// Array of arrays:
|
|
zipped = zip( arr, { 'arrays': true } );
|
|
// returns [ [ 1, 'a' ], [ 2, 'b' ] ]
|
|
```
|
|
|
|
</section>
|
|
|
|
<!-- /.usage -->
|
|
|
|
<section class="examples">
|
|
|
|
## Examples
|
|
|
|
<!-- eslint no-undef: "error" -->
|
|
|
|
```javascript
|
|
var randu = require( '@stdlib/random/base/randu' );
|
|
var zip = require( '@stdlib/utils/zip' );
|
|
|
|
var zipped;
|
|
var len;
|
|
var y1;
|
|
var y2;
|
|
var y3;
|
|
var x;
|
|
var i;
|
|
|
|
// Simulate some data...
|
|
x = new Array( 100 );
|
|
len = x.length;
|
|
y1 = new Array( len );
|
|
y2 = new Array( len );
|
|
y3 = new Array( len );
|
|
|
|
for ( i = 0; i < len; i++ ) {
|
|
x[ i ] = Date.now();
|
|
y1[ i ] = randu() * 100;
|
|
y2[ i ] = randu() * 100;
|
|
y3[ i ] = randu();
|
|
}
|
|
|
|
zipped = zip( x, y1, y2, y3 );
|
|
|
|
console.log( zipped.join( '\n' ) );
|
|
```
|
|
|
|
</section>
|
|
|
|
<!-- /.examples -->
|
|
|
|
<section class="links">
|
|
|
|
</section>
|
|
|
|
<!-- /.links -->
|