Gapotchenko.FX.Math.Metrics 2024.1.3

Overview

The module provides math metrics algorithms.

String Metrics

Gapotchenko.FX.Math.Metrics.StringMetrics class provides a variety of algorithms for measuring the distance and similarity between two strings of symbols.

The notion of a string is purely abstract. So it is not limited to just System.String of characters; it can be a string of anything in the form of IEnumerable<T> sequence of elements. In this way, Gapotchenko.FX.Math.Metrics module achieves the right degree of abstraction desirable for a versatile math toolkit.

Edit Distance

Edit distance is a string metric reflecting the minimum number of operations required to transform one string into the other. There are several ways to measure the edit distance.

The table below compares metric functions provided by StringMetrics class:

Levenshtein Distance

StringMetrics.Distance.Levenshtein algorithm allows you to calculate the Levenshtein distance between two strings of symbols.

Consider an example:

using Gapotchenko.FX.Math.Metrics;

int distance = StringMetrics.Distance.Levenshtein.Calculate("ABC", "BAC");
Console.WriteLine("Distance is {0}.", distance);  // distance = 2

Longest Common Subsequence (LCS) Distance

StringMetrics.Distance.Lcs algorithm allows you to calculate the longest common subsequence (LCS) distance between two strings of symbols.

Consider an example:

using Gapotchenko.FX.Math.Metrics;

int distance = StringMetrics.Distance.Lcs.Calculate("ABC", "BAC");
Console.WriteLine("Distance is {0}.", distance);  // distance = 2

Hamming Distance

StringMetrics.Distance.Hamming algorithm allows you to calculate the Hamming distance between two strings of symbols.

Consider an example:

using Gapotchenko.FX.Math.Metrics;

int distance = StringMetrics.Distance.Hamming.Calculate("ABC", "BAC");
Console.WriteLine("Distance is {0}.", distance);  // distance = 2

Please note that the Hamming distance can only be calculated between two string of an equal length.

Damerau-Levenshtein Distance

StringMetrics.Distance.DamerauLevenshtein algorithm allows you to calculate the Damerau–Levenshtein distance between two strings of symbols.

Consider an example:

using Gapotchenko.FX.Math.Metrics;

int distance = StringMetrics.Distance.DamerauLevenshtein.Calculate("ABC", "BAC");
Console.WriteLine("Distance is {0}.", distance);  // distance = 1

Optimal String Alignment (OSA) Distance

StringMetrics.Distance.Osa algorithm allows you to calculate the optimal string alignment (OSA) distance between two strings of symbols.

Consider an example:

using Gapotchenko.FX.Math.Metrics;

int distance = StringMetrics.Distance.Osa.Calculate("ABC", "BAC");
Console.WriteLine("Distance is {0}.", distance);  // distance = 1

Jaro Similarity

StringMetrics.Similarity.Jaro algorithm allows you to calculate the Jaro distance between two strings of symbols.

Although the Jaro similarity is often referred to as an edit distance metric, its value does not represent a number of edit operations and varies between 0.0 and 1.0 such that 1.0 represents an exact match and 0.0 equates to no similarities.

Consider an example:

using Gapotchenko.FX.Math.Metrics;

double similarity = StringMetrics.Similarity.Jaro.Calculate("ABC", "BAC");
Console.WriteLine("Similarity is {0.00}.", similarity);  // similarity = 0.36

Commonly Used Types

• Gapotchenko.FX.Math.Metrics.StringMetrics

Other Modules

Let's continue with a look at some other modules provided by Gapotchenko.FX:

• Gapotchenko.FX
• Gapotchenko.FX.AppModel.Information
• Gapotchenko.FX.Collections
• Gapotchenko.FX.Console
• Gapotchenko.FX.Data
• Gapotchenko.FX.Diagnostics
• Gapotchenko.FX.IO
• Gapotchenko.FX.Linq
• Gapotchenko.FX.Math
  • Gapotchenko.FX.Math.Combinatorics
  • Gapotchenko.FX.Math.Graphs
  • Gapotchenko.FX.Math.Intervals
  • ➴ Gapotchenko.FX.Math.Metrics
• Gapotchenko.FX.Memory
• Gapotchenko.FX.Security.Cryptography
• Gapotchenko.FX.Text
• Gapotchenko.FX.Threading
• Gapotchenko.FX.Tuples

Or look at the full list of modules.