compute-anagram-hash

Anagram Hash
===
[![NPM version][npm-image]][npm-url] [![Build Status][travis-image]][travis-url] [![Coverage Status][coveralls-image]][coveralls-url] [![Dependencies][dependencies-image]][dependencies-url]

> Anagram hash table.

Installation

`` bash
$ npm install compute-anagram-hash
`

For use in the browser, use browserify.

Usage

` javascript
var createHash = require( 'compute-anagram-hash' );
`

#### createHash( [arr] )

Creates an anagram hash table.

` javascript
var hash = createHash();
`

To initialize the hash table, provide a string array.

` javascript
var arr = [
'beep',
'boop',
'bop',
'bap',
'foo',
'bar',
'cat',
'bat',
'moot',
'woot',
'moto',
'tab',
'pad',
'Shakespeare is awesome!'
];

var hash = createHash( arr );
`

The hash table has the following methods...

#### hash.push( str[, str,...,str] )

Add strings to the anagram hash table.

` javascript
hash.push( 'dog', 'rad', 'super' );
`


#### hash.get( [str[, key]] )

Returns a list of anagrams. If provided an input string, the method returns a list of corresponding anagrams from the hash table; otherwise, the method returns all anagram lists. If no anagrams exist, the method returns null.

` javascript
// Get all anagrams:
var lists = hash.get();
// returns [['bat','tab'],['moot','moto']]

// Get anagrams corresponding to a particular string:
var list = hash.get( 'moot' );
// returns ['moto']

list = hash.get( 'beep' );
// returns null
`

If the input string is a hash __key__, set the key flag to true. When provided a hash __key__, the method returns all anagrams associated with a particular __key__ (possibly including the __key__ itself).

` javascript
var list = hash.get( 'abt', true );
// returns ['bat','tab']

list = hash.get( 'beep', true );
// returns ['beep']
`

__Note__: when returning all anagram lists, the list order is __not__ guaranteed.

#### hash.getKey( str )

Hashing function. Converts an input string to an alphagram.

` javascript
var key = hash.getKey( 'tab' );
// returns 'abt'

var list = hash.get( key, true );
// returns ['bat','tab']
`

__Note__: the returned __key__ only contains lowercase alphanumeric characters.


#### hash.keys( [opts] )

Returns a list of hash __keys__.

` javascript
var keys = hash.keys();
// returns ['abp','abr','abt','act',...]
`

The method accepts the following options:

* __min__: minimum number of anagrams.
* __max__: maximum number of anagrams.

To return keys having at least a min number of anagrams, set the min option.

` javascript
var keys = hash.keys({ 'min': 2 });
// returns ['abt','moot']
`

To return keys having at most a max number of anagrams, set the max option.

` javascript
var keys = hash.keys({ 'max': 1 });
// returns ['abp','abr','act','adp',...]
`


#### hash.merge( hash1[, hash2,...,hashN] )

Merges anagram hash tables into the current anagram hash instance.

` javascript
var mhash1, mhash2;

mhash1 = createHash( ['yes','no'] );
mhash2 = createHash( ['beep','bepe'] );

hash.merge( mhash1, mhash2 );

var list = hash.get( 'beep', true );
// returns ['beep','bepe']
`


#### hash.copy( [keys] )

Copies an anagram hash table to a new hash table instance.

` javascript
var copy = hash.copy();

var list = copy.get( 'abt', true );
// returns ['bat','tab']
`

To only copy specific __keys__ to a new hash table, provide a __keys__ array.

` javascript
var copy = hash.copy( ['beep'] );

var keys = copy.keys();
// returns ['beep']
`

Examples

` javascript
var createHash = require( 'compute-anagram-hash' );

// Load a string array containing tokenized words:
var words = require( './words.json' );

// Create a new hash:
var hash = createHash( words );

// Get all anagram lists:
var lists = hash.get();

// Get a single anagram list:
var list = hash.get( 'rome' );
`

To run the example code from the top-level application directory,

` bash
$ node ./examples/index.js
`

Tests

$3

Unit tests use the Mocha test framework with Chai assertions. To run the tests, execute the following command in the top-level application directory:

` bash
$ make test
`

All new feature development should have corresponding unit tests to validate correct functionality.

$3

This repository uses Istanbul as its code coverage tool. To generate a test coverage report, execute the following command in the top-level application directory:

` bash
$ make test-cov
`

Istanbul creates a ./reports/coverage directory. To access an HTML version of the report,

` bash
$ make view-cov
``

---

License

MIT license.

Copyright

Copyright © 2015. Athan Reines.

[npm-image]: http://img.shields.io/npm/v/compute-anagram-hash.svg
[npm-url]: https://npmjs.org/package/compute-anagram-hash

[travis-image]: http://img.shields.io/travis/compute-io/anagram-hash/master.svg
[travis-url]: https://travis-ci.org/compute-io/anagram-hash

[coveralls-image]: https://img.shields.io/coveralls/compute-io/anagram-hash/master.svg
[coveralls-url]: https://coveralls.io/r/compute-io/anagram-hash?branch=master

[dependencies-image]: http://img.shields.io/david/compute-io/anagram-hash.svg
[dependencies-url]: https://david-dm.org/compute-io/anagram-hash

[dev-dependencies-image]: http://img.shields.io/david/dev/compute-io/anagram-hash.svg
[dev-dependencies-url]: https://david-dm.org/dev/compute-io/anagram-hash

[github-issues-image]: http://img.shields.io/github/issues/compute-io/anagram-hash.svg
[github-issues-url]: https://github.com/compute-io/anagram-hash/issues