32 lines
871 B
C#
32 lines
871 B
C#
using System;
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using System.Collections.Generic;
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using System.Linq;
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using System.Text;
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using System.Text.RegularExpressions;
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using BotSharp.NLP.Tokenize;
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namespace BotSharp.NLP.Stem
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{
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/// <summary>
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/// A stemmer that uses regular expressions to identify morphological affixes.
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/// Any substrings that match the regular expressions will be removed.
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/// </summary>
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public class RegexStemmer : IStemmer
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{
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public const string DEFAULT = "ing$|s$|e$|able$";
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public SupportedLanguage Lang { get; set; }
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private Regex _regex;
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public string Stem(string word, StemOptions options)
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{
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_regex = new Regex(options.Pattern);
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var match = _regex.Matches(word).Cast<Match>().FirstOrDefault();
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return match == null ? word : word.Substring(0, match.Index);
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}
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}
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}
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