mosesdecoder/moses/FF/TreeStructureFeature.cpp

316 lines
9.2 KiB
C++

#include "TreeStructureFeature.h"
#include "moses/StaticData.h"
#include "moses/ScoreComponentCollection.h"
#include "moses/Hypothesis.h"
#include "moses/ChartHypothesis.h"
#include "moses/TargetPhrase.h"
#include <boost/shared_ptr.hpp>
#include <vector>
using namespace std;
namespace Moses
{
InternalTree::InternalTree(const std::string & line, const bool terminal):
m_value_nt(0),
m_isTerminal(terminal)
{
size_t found = line.find_first_of("[] ");
if (found == line.npos) {
m_value = line;
}
else {
AddSubTree(line, 0);
}
}
size_t InternalTree::AddSubTree(const std::string & line, size_t pos) {
std::string value = "";
char token = 0;
while (token != ']' && pos != std::string::npos)
{
size_t oldpos = pos;
pos = line.find_first_of("[] ", pos);
if (pos == std::string::npos) break;
token = line[pos];
value = line.substr(oldpos,pos-oldpos);
if (token == '[') {
if (m_value.size() > 0) {
TreePointer child(new InternalTree(value, false));
m_children.push_back(child);
pos = child->AddSubTree(line, pos+1);
}
else {
if (value.size() > 0) {
m_value = value;
}
pos = AddSubTree(line, pos+1);
}
}
else if (token == ' ' || token == ']') {
if (value.size() > 0 && ! m_value.size() > 0) {
m_value = value;
}
else if (value.size() > 0) {
m_isTerminal = false;
TreePointer child(new InternalTree(value, true));
m_children.push_back(child);
}
if (token == ' ') {
pos++;
}
}
if (m_children.size() > 0) {
m_isTerminal = false;
}
}
if (pos == std::string::npos) {
return line.size();
}
return min(line.size(),pos+1);
}
std::string InternalTree::GetString() const {
std::string ret = " ";
if (!m_isTerminal) {
ret += "[";
}
ret += m_value;
for (std::vector<TreePointer>::const_iterator it = m_children.begin(); it != m_children.end(); ++it)
{
ret += (*it)->GetString();
}
if (!m_isTerminal) {
ret += "]";
}
return ret;
}
void InternalTree::Combine(const std::vector<TreePointer> &previous) {
std::vector<TreePointer>::iterator it;
bool found = false;
leafNT next_leafNT(this);
for (std::vector<TreePointer>::const_iterator it_prev = previous.begin(); it_prev != previous.end(); ++it_prev) {
found = next_leafNT(it);
if (found) {
*it = *it_prev;
}
else {
std::cerr << "Warning: leaf nonterminal not found in rule; why did this happen?\n";
}
}
}
bool InternalTree::FlatSearch(const std::string & label, std::vector<TreePointer>::const_iterator & it) const {
for (it = m_children.begin(); it != m_children.end(); ++it) {
if ((*it)->GetLabel() == label) {
return true;
}
}
return false;
}
bool InternalTree::RecursiveSearch(const std::string & label, std::vector<TreePointer>::const_iterator & it) const {
for (it = m_children.begin(); it != m_children.end(); ++it) {
if ((*it)->GetLabel() == label) {
return true;
}
std::vector<TreePointer>::const_iterator it2;
if ((*it)->RecursiveSearch(label, it2)) {
it = it2;
return true;
}
}
return false;
}
bool InternalTree::RecursiveSearch(const std::string & label, std::vector<TreePointer>::const_iterator & it, InternalTree const* &parent) const {
for (it = m_children.begin(); it != m_children.end(); ++it) {
if ((*it)->GetLabel() == label) {
parent = this;
return true;
}
std::vector<TreePointer>::const_iterator it2;
if ((*it)->RecursiveSearch(label, it2, parent)) {
it = it2;
return true;
}
}
return false;
}
bool InternalTree::FlatSearch(const NTLabel & label, std::vector<TreePointer>::const_iterator & it) const {
for (it = m_children.begin(); it != m_children.end(); ++it) {
if ((*it)->GetNTLabel() == label) {
return true;
}
}
return false;
}
bool InternalTree::RecursiveSearch(const NTLabel & label, std::vector<TreePointer>::const_iterator & it) const {
for (it = m_children.begin(); it != m_children.end(); ++it) {
if ((*it)->GetNTLabel() == label) {
return true;
}
std::vector<TreePointer>::const_iterator it2;
if ((*it)->RecursiveSearch(label, it2)) {
it = it2;
return true;
}
}
return false;
}
bool InternalTree::RecursiveSearch(const NTLabel & label, std::vector<TreePointer>::const_iterator & it, InternalTree const* &parent) const {
for (it = m_children.begin(); it != m_children.end(); ++it) {
if ((*it)->GetNTLabel() == label) {
parent = this;
return true;
}
std::vector<TreePointer>::const_iterator it2;
if ((*it)->RecursiveSearch(label, it2, parent)) {
it = it2;
return true;
}
}
return false;
}
bool InternalTree::FlatSearch(const std::vector<NTLabel> & labels, std::vector<TreePointer>::const_iterator & it) const {
for (it = m_children.begin(); it != m_children.end(); ++it) {
if (std::binary_search(labels.begin(), labels.end(), (*it)->GetNTLabel())) {
return true;
}
}
return false;
}
bool InternalTree::RecursiveSearch(const std::vector<NTLabel> & labels, std::vector<TreePointer>::const_iterator & it) const {
for (it = m_children.begin(); it != m_children.end(); ++it) {
if (std::binary_search(labels.begin(), labels.end(), (*it)->GetNTLabel())) {
return true;
}
std::vector<TreePointer>::const_iterator it2;
if ((*it)->RecursiveSearch(labels, it2)) {
it = it2;
return true;
}
}
return false;
}
bool InternalTree::RecursiveSearch(const std::vector<NTLabel> & labels, std::vector<TreePointer>::const_iterator & it, InternalTree const* &parent) const {
for (it = m_children.begin(); it != m_children.end(); ++it) {
if (std::binary_search(labels.begin(), labels.end(), (*it)->GetNTLabel())) {
parent = this;
return true;
}
std::vector<TreePointer>::const_iterator it2;
if ((*it)->RecursiveSearch(labels, it2, parent)) {
it = it2;
return true;
}
}
return false;
}
void TreeStructureFeature::Load() {
// syntactic constraints can be hooked in here.
m_constraints = NULL;
m_labelset = NULL;
StaticData &staticData = StaticData::InstanceNonConst();
staticData.SetTreeStructure(this);
}
// define NT labels (ints) that are mapped from strings for quicker comparison.
void TreeStructureFeature::AddNTLabels(TreePointer root) const {
std::string label = root->GetLabel();
if (root->IsTerminal()) {
return;
}
std::map<std::string, NTLabel>::const_iterator it = m_labelset->string_to_label.find(label);
if (it != m_labelset->string_to_label.end()) {
root->SetNTLabel(it->second);
}
std::vector<TreePointer> children = root->GetChildren();
for (std::vector<TreePointer>::const_iterator it2 = children.begin(); it2 != children.end(); ++it2) {
AddNTLabels(*it2);
}
}
FFState* TreeStructureFeature::EvaluateChart(const ChartHypothesis& cur_hypo
, int featureID /* used to index the state in the previous hypotheses */
, ScoreComponentCollection* accumulator) const
{
std::string tree;
bool found = 0;
cur_hypo.GetCurrTargetPhrase().GetProperty("Tree", tree, found);
if (found) {
TreePointer mytree (new InternalTree(tree));
if (m_labelset) {
AddNTLabels(mytree);
}
//get subtrees (in target order)
std::vector<TreePointer> previous_trees;
for (size_t pos = 0; pos < cur_hypo.GetCurrTargetPhrase().GetSize(); ++pos) {
const Word &word = cur_hypo.GetCurrTargetPhrase().GetWord(pos);
if (word.IsNonTerminal()) {
size_t nonTermInd = cur_hypo.GetCurrTargetPhrase().GetAlignNonTerm().GetNonTermIndexMap()[pos];
const ChartHypothesis *prevHypo = cur_hypo.GetPrevHypo(nonTermInd);
const TreeState* prev = dynamic_cast<const TreeState*>(prevHypo->GetFFState(featureID));
const TreePointer prev_tree = prev->GetTree();
previous_trees.push_back(prev_tree);
}
}
std::vector<std::string> sparse_features;
if (m_constraints) {
sparse_features = m_constraints->SyntacticRules(mytree, previous_trees);
}
mytree->Combine(previous_trees);
//sparse scores
for (std::vector<std::string>::const_iterator feature=sparse_features.begin(); feature != sparse_features.end(); ++feature) {
accumulator->PlusEquals(this, *feature, 1);
}
return new TreeState(mytree);
}
else {
UTIL_THROW2("Error: TreeStructureFeature active, but no internal tree structure found");
}
}
}