time-to-botec/js/node_modules/@stdlib/utils/zip/README.md

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@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
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# 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 -->