node package manager

keyword-extractor

Keyword Extractor

A simple NPM package for extracting keywords from a string by removing stopwords.

Installation

$ npm install keyword-extractor

Running tests

To run the test suite, first install the development dependencies by running the following command within the package's directory.

$ npm install

To execute the package's tests, run:

$ make test

Usage of the Module

//  include the Keyword Extractor 
var keyword_extractor = require("keyword-extractor");
 
//  Opening sentence to NY Times Article at 
//  http://www.nytimes.com/2013/09/10/world/middleeast/surprise-russian-proposal-catches-obama-between-putin-and-house-republicans.html 
var sentence = "President Obama woke up Monday facing a Congressional defeat that many in both parties believed could hobble his presidency."
 
//  Extract the keywords 
var extraction_result = keyword_extractor.extract(sentence,{
                                                                language:"english",
                                                                remove_digits: true,
                                                                return_changed_case:true,
                                                                remove_duplicates: false
 
                                                           });
 
/*
  extraction result is:
 
  [
        "president",
        "obama",
        "woke",
        "monday",
        "facing",
        "congressional",
        "defeat",
        "parties",
        "believed",
        "hobble",
        "presidency"
    ]
*/

Options Parameters

The second argument of the extract method is an Object of configuration/processing settings for the extraction.

Parameter Name Description Permitted Values
language The stopwords list to use. english, spanish, polish, german, french, italian, dutch, russian,portuguese,swedish,
remove_digits Removes all digits from the results if set to true true or false
return_changed_case The case of the extracted keywords. Setting the value to true will return the results all lower-cased, if false the results will be in the original case. true or false
return_chained_words Instead of returning each word separately, join the words that were originally together. Setting the value to true will join the words, if false the results will be splitted on each array element. true or false
remove_duplicates Removes the duplicate keywords true , false (defaults to false )

Credits

The initial stopwords lists are taken from the following sources:

  • English [http://jmlr.org/papers/volume5/lewis04a/a11-smart-stop-list/english.stop]
  • Spanish [https://stop-words.googlecode.com/svn/trunk/stop-words/stop-words/stop-words-spanish.txt]