Communary.PASM

PowerShell Approximate String Matching

This module contains three main functions for doing approximate string matching using the following methods:

• Fuzzy Search
• Soundex
• Approximate String Matching algorithms

All of the string matching algorithms are included as stand-alone functions, and can be used outside of this module.

There is also a helper function for comparing the included approximate string matching algorithms against each other.

Approximate String Matching Algorithms

• Overlap Coefficient
• Longest Common Substring
• Longest Common Subsequence
• Hamming Distance
• Ratcliff/Obershelp Similarity
• Jaccard Index
• Jaccard Distance
• Sorensen-Dice Coefficient
• Sorensen-Dice Distance
• Jaro Distance
• Jaro-Winkler Distance
• Levenshtein Distance

Fuzzy Search Algorithm

This algorithm is basically a wildcard search (where a wildcard is placed before and after each character in the search query), but additionally it will calculate a score according to this set of rules:

• An initial score of 100 is given for anything that matches the query
• The Levenshtein Distance is subtracted from the score
• The length of the longest common substring are multiplied with the score
• The length of the shortest regex match is subtracted from the score
• The length of the index of the regex match is subtracted from the score
• If a common prefix exists, the length of this is added to the score

Installation

If you have PowerShellGet, you can install it with:

Install-Module Communary.PASM

Else, you would have to download the zip from this repository and manually unpack it to one of the module paths on your system.

How to use

All functions (should) have built-in help with examples of how to use them.

Also, check out Tests\examples.ps1 for a couple of examples.