# stopword
`stopword` is a node module that allows you to strip stopwords from an
input text. [In natural language processing, "Stopwords" are words
that are so frequent that they can safely be removed from a text
without altering its
meaning.](https://en.wikipedia.org/wiki/Stop_words)


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[![NPM downloads][npm-downloads-image]][npm-url]
[![MIT License][license-image]][license-url]
[![Build Status][travis-image]][travis-url]


## Usage

By default, `stopword` will strip an array of "meaningless" English words

```javascript
sw = require('stopword')
const oldString = 'a really Interesting string with some words'.split(' ')
const newString = sw.removeStopwords(oldString)
// newString is now [ 'really', 'Interesting', 'string', 'words' ]

```

You can also specify a language other than english:
```javascript
sw = require('stopword')
const oldString = 'Trädgårdsägare är beredda att pröva vad som helst för att bli av med de hatade mördarsniglarna åäö'.split(' ')
// sw.sv contains swedish stopwords
const newString = sw.removeStopwords(oldString, sw.sv)
// newString is now [ 'Trädgårdsägare', 'beredda', 'pröva', 'helst', 'hatade', 'mördarsniglarna', 'åäö' ]
```

## API

### <language code>

Arrays of stopwords for the following languages are supplied: 

* `ar` - Modern Standard Arabic
* `bn` - Bengali
* `da` - Danish
* `de` - German
* `en` - English
* `es` - Spanish
* `fa` - Farsi
* `fr` - French
* `hi` - Hindi
* `it` - Italian
* `ja` - Japanese
* `nl` - Dutch
* `no` - Norwegian
* `pl` - Polish
* `pt` - Portuguese
* `ru` - Russioan
* `sv` - Sweedish
* `zh` - Chinese Simplified

```javascript
sw = require('stopword')
norwegianStopwords = sw.no
// norwegianStopwords now contains an Array of norwgian stopwords
```

#### Languages with no space between words
`ja` Japanese and `zh` Chinese Simplified have no space between words. For these languages you need to split the text into words before feeding it to the `stopword` module. You can check out [TinySegmenter](http://chasen.org/%7Etaku/software/TinySegmenter/) for Japanese and [chinese-tokenizer](https://github.com/yishn/chinese-tokenizer) for Chinese.

### removeStopwords

Returns an Array that represents the text with the specified stopwords removed.

* `text` An array of words
* `stopwords` An array of stopwords

```javascript
sw = require('stopword')
var text = sw.removeStopwords(text[, stopwords])
// text is now an array of given words minus specified stopwords
```


## Release Notes:

version 0.0.4, `removeStopwords` returns an Array, since this
removes ambiguity around separators.

version 0.1.0 `getStopwords` removed in favour of constants. `removeStopwords` takes text as an Array

version 0.1.2 Updated to ES6 simplified syntax

version 0.1.5 Making syntax ES5 compatible again

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[license-url]: LICENSE
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