https://github.com/mikolalysenko/partition-array

Partitions an array by a predicate
https://github.com/mikolalysenko/partition-array

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Partitions an array by a predicate

• Host: GitHub
• URL: https://github.com/mikolalysenko/partition-array
• Owner: mikolalysenko
• License: mit
• Created: 2015-02-08T23:43:33.000Z (almost 10 years ago)
• Default Branch: master
• Last Pushed: 2015-02-08T23:52:53.000Z (almost 10 years ago)
• Last Synced: 2024-10-21T15:38:12.664Z (2 months ago)
• Language: JavaScript
• Size: 117 KB
• Stars: 6
• Watchers: 3
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

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README

        
partition-array

===============

Linear time in place array partitioning.  Similar to `Array.filter`, but faster as it does not make a copy.

# Example

```javascript

var partition = require('partition-array')

var array = [1, 0, -1, 10, -5, 6, -8, -7]

var split = partition(array, function(x) {

  return x < 0

})

console.log('partition @', split)

console.log(array)

console.log('<0   ~', array.slice(0, split))

console.log('>=0  ~', array.slice(split))

```

Output:

```

partition @ 4

[ -1, -5, -8, -7, 0, 6, 1, 10 ]

<0   ~ [ -1, -5, -8, -7 ]

>=0  ~ [ 0, 6, 1, 10 ]

```

# Install

```

npm install partition-array

```

# API

#### `var split = require('partition-array')(array, pred[, lo, hi])`

Partitions the array into two contiguous regions based on predicate.

* `array` is the array which is to be partitioned

* `pred` is the predicate which is being tested

* `lo` is an optional parameter denoting the start of the subarray to partition (default `0`)

* `hi` is an optional parameter denoting the end of the subarray to partition (default `array.length`)

**Returns** The point at which the array was split.  For elements in the array before index `mid`, `pred` is true; for elements after `mid` `pred` is false.

# License

(c) 2015 Mikola Lysenko. MIT License