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comparison Implab/Automaton/IndexedAlphabetBase.cs @ 192:f1da3afc3521 release v2.1

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Слияние с v2
author cin
date Fri, 22 Apr 2016 13:10:34 +0300
parents c32688129f14
children
comparison
equal deleted inserted replaced
71:1714fd8678ef 192:f1da3afc3521
1 using Implab;
2 using System;
3 using System.Collections.Generic;
4 using System.Diagnostics;
5 using System.Linq;
6
7 namespace Implab.Automaton {
8 /// <summary>
9 /// Indexed alphabet is the finite set of symbols where each symbol has a zero-based unique index.
10 /// </summary>
11 /// <remarks>
12 /// Indexed alphabets are usefull in bulting efficient translations from source alphabet
13 /// to the input alphabet of the automaton. It's assumed that the index to the symbol match
14 /// is well known and documented.
15 /// </remarks>
16 public abstract class IndexedAlphabetBase<T> : MapAlphabet<T> {
17
18 protected IndexedAlphabetBase() :base(true, null) {
19 }
20
21 public abstract int GetSymbolIndex(T symbol);
22
23 /// <summary>
24 /// Gets the translation map from the index of the symbol to it's class this is usefull for the optimized input symbols transtaion.
25 /// </summary>
26 /// <remarks>
27 /// The map is continous and start from the symbol with zero code. The last symbol
28 /// in the map is the last classified symbol in the alphabet, i.e. the map can be
29 /// shorter then the whole alphabet.
30 /// </remarks>
31 /// <returns>The translation map.</returns>
32 public int[] GetTranslationMap() {
33 var map = new Dictionary<int, int>();
34
35 int max = 0;
36 foreach (var p in Mappings) {
37 var index = GetSymbolIndex(p.Key);
38 max = Math.Max(max, index);
39 map[index] = p.Value;
40 }
41
42 var result = new int[max + 1];
43
44 for (int i = 0; i < result.Length; i++)
45 map.TryGetValue(i, out result[i]);
46
47 return result;
48 }
49 }
50 }