Fuzzybear

Fuzzybear is a JavaScript library for fuzzy string search with a special focus on short strings. It is designed to use multiple string distance functions (including custom) but by default it uses a combination of Jaro-Winkler and Jaccard string distances. The former favours matches from the beginning of a string, while the latter splits the string into tokens and analyses those. Together these provide a reasonable performance for most cases, but the library allows the user to customise the methods and parameters for searching.

Usage

Subset Search

fuzzybear.search is the primary method used for searching. It accepts either a string array or an object. array where each element contains a key value.

let matches = [ 'Identical', 'Identifier', 'dentical', 'Dental', 'dentist', 'different' ]
// OR
let matches = [
    { value:'Identical', id: 's0' },
    { value:'Identifier', id: 's1' },
    { value:'dentical', id: 's2' },
    { value:'Dental', id: 's3' },
    { value:'dentist', id: 's4' },
    { value:'Different', id: 's5' },
]
fuzzybear.search( 'Identical', matches )

You can also restrict the number of results returned:

fuzzybear.search( 'Identical', matches, { results: 3 })

Manual scoring

fuzzybear.score( 'prism', 'contact' )    // => 0
fuzzybear.score( 'prism', 'prism' )      // => 1
fuzzybear.score( 'prism', 'unpristine' ) // => 0.56

Advanced usage

Search method parameters

You can pass custom methods and/or use one of the implemented methods in fuzzybear. You can also specify certain method parameters to override the method's behaviour. For example, you can use a minimum of 3 letter substring matches in the Jaccard search method to ignore matches with less than 3 letters.

fuzzybear.search( 'Identical', matches, {
    methods: [
        {
            name: 'jaccard',
            params: { n: 3 } // Minimum ngram length
        }
    ]
})

Custom search function

You can also pass a custom scoring function to the search method. The function takes 3 parameters: the search term, the target string and the method parameters. The function should return a number between 0 and 1, where 0 is a perfect match (meaning the string distance is 0).

fuzzybear.search( 'asd', [ 'a', 'b', 'c', 'd' ], {
    methods: [
        {
            name: 'match-all',
            function: function( _a, _b, _params ){
                return 0.36
            }
        }
    ]
})

API

fuzzybear.search( term, matches, options ) // Perform a fuzzy string search across a list of elements.
fuzzybear.score( term, match, options ) // Perform a fuzzy string distance of two strings.

Configuration options

/**
 * @param {Number}   options.results - Number of results to return. Defaults to 0 - all elements distanced
 * @param {String}   options.labelField - Field to search against. Defaults to "label"
 * @param {Boolean}  options.caseSensitive - Whether to perform a case sensitive match. Defaults to false
 * @param {Number}   options.minScore - Minimum score of matches to be included in the results
 * @param {Object[]} options.methods - Which methods to use when scoring matches
 * @param {String}   options.methods[].name - Search algorithm name
 * @param {Object}   options.methods[].function - A custom search algorithm function. The function takes
 * @param {Number}   options.methods[].weight - Search algorithm weight in scoring
 * @param {Object}   options.methods[].params - Search algorithm parameters
 */

PR's accepted for:

• Search methods that support longer text and using a tokenised approach (and maybe even re-using the standard string distance methods).
• Support for string pre-processors

• UTF-8 to ASCII conversion for symbols like: äáčďéíöóúüñ¿¡Æ
• Metaphone conversion

License

All code and documentation are licensed under the MIT license, although permission is not granted for using this code as a sample data for training machine learning networks.