File size: 5,181 Bytes
158b61b
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
/*
 * AlignedSentence.cpp
 *
 *  Created on: 18 Feb 2014
 *      Author: s0565741
 */

#include <sstream>
#include "moses/Util.h"
#include "AlignedSentence.h"
#include "Parameter.h"

using namespace std;


/////////////////////////////////////////////////////////////////////////////////
AlignedSentence::AlignedSentence(int lineNum,
                                 const std::string &source,
                                 const std::string &target,
                                 const std::string &alignment)
  :m_lineNum(lineNum)
{
  PopulateWordVec(m_source, source);
  PopulateWordVec(m_target, target);
  PopulateAlignment(alignment);
}

AlignedSentence::~AlignedSentence()
{
  Moses::RemoveAllInColl(m_source);
  Moses::RemoveAllInColl(m_target);
}

void AlignedSentence::PopulateWordVec(Phrase &vec, const std::string &line)
{
  std::vector<string> toks;
  Moses::Tokenize(toks, line);

  vec.resize(toks.size());
  for (size_t i = 0; i < vec.size(); ++i) {
    const string &tok = toks[i];
    Word *word = new Word(i, tok);
    vec[i] = word;
  }
}

void AlignedSentence::PopulateAlignment(const std::string &line)
{
  vector<string> alignStr;
  Moses::Tokenize(alignStr, line);

  for (size_t i = 0; i < alignStr.size(); ++i) {
    vector<int> alignPair;
    Moses::Tokenize(alignPair, alignStr[i], "-");
    assert(alignPair.size() == 2);

    int sourcePos = alignPair[0];
    int targetPos = alignPair[1];

    if (sourcePos >= m_source.size()) {
      cerr << "ERROR1:AlignedSentence=" << Debug() << endl;
      cerr << "m_source=" << m_source.size() << endl;
      abort();
    }
    assert(sourcePos < m_source.size());
    assert(targetPos < m_target.size());
    Word *sourceWord = m_source[sourcePos];
    Word *targetWord = m_target[targetPos];

    sourceWord->AddAlignment(targetWord);
    targetWord->AddAlignment(sourceWord);
  }
}

std::string AlignedSentence::Debug() const
{
  stringstream out;
  out << "m_lineNum:";
  out << m_lineNum;
  out << endl;

  out << "m_source:";
  out << m_source.Debug();
  out << endl;

  out << "m_target:";
  out << m_target.Debug();
  out << endl;

  out << "consistent phrases:" << endl;
  out << m_consistentPhrases.Debug();
  out << endl;

  return out.str();
}

std::vector<int> AlignedSentence::GetSourceAlignmentCount() const
{
  vector<int> ret(m_source.size());

  for (size_t i = 0; i < m_source.size(); ++i) {
    const Word &word = *m_source[i];
    ret[i] = word.GetAlignmentIndex().size();
  }
  return ret;
}

void AlignedSentence::Create(const Parameter &params)
{
  CreateConsistentPhrases(params);
  m_consistentPhrases.AddHieroNonTerms(params);
}

void AlignedSentence::CreateConsistentPhrases(const Parameter &params)
{
  int countT = m_target.size();
  int countS = m_source.size();

  m_consistentPhrases.Initialize(countS);

  // check alignments for target phrase startT...endT
  for(int lengthT=1;
      lengthT <= params.maxSpan && lengthT <= countT;
      lengthT++) {
    for(int startT=0; startT < countT-(lengthT-1); startT++) {

      // that's nice to have
      int endT = startT + lengthT - 1;

      // find find aligned source words
      // first: find minimum and maximum source word
      int minS = 9999;
      int maxS = -1;
      vector< int > usedS = GetSourceAlignmentCount();
      for(int ti=startT; ti<=endT; ti++) {
        const Word &word = *m_target[ti];
        const std::set<int> &alignment = word.GetAlignmentIndex();

        std::set<int>::const_iterator iterAlign;
        for(iterAlign = alignment.begin(); iterAlign != alignment.end(); ++iterAlign) {
          int si = *iterAlign;
          if (si<minS) {
            minS = si;
          }
          if (si>maxS) {
            maxS = si;
          }
          usedS[ si ]--;
        }
      }

      // unaligned phrases are not allowed
      if( maxS == -1 )
        continue;

      // source phrase has to be within limits
      size_t width = maxS - minS + 1;

      if( width < params.minSpan )
        continue;

      if( width > params.maxSpan )
        continue;

      // check if source words are aligned to out of bound target words
      bool out_of_bounds = false;
      for(int si=minS; si<=maxS && !out_of_bounds; si++)
        if (usedS[si]>0) {
          out_of_bounds = true;
        }

      // if out of bound, you gotta go
      if (out_of_bounds)
        continue;

      // done with all the checks, lets go over all consistent phrase pairs
      // start point of source phrase may retreat over unaligned
      for(int startS=minS;
          (startS>=0 &&
           startS>maxS - params.maxSpan && // within length limit
           (startS==minS || m_source[startS]->GetAlignment().size()==0)); // unaligned
          startS--) {
        // end point of source phrase may advance over unaligned
        for(int endS=maxS;
            (endS<countS && endS<startS + params.maxSpan && // within length limit
             (endS==maxS || m_source[endS]->GetAlignment().size()==0)); // unaligned
            endS++) {

          // take note that this is a valid phrase alignment
          m_consistentPhrases.Add(startS, endS, startT, endT, params);
        }
      }
    }
  }
}