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#include "ff_spans.h"
#include <sstream>
#include <cassert>
#include "filelib.h"
#include "stringlib.h"
#include "sentence_metadata.h"
#include "lattice.h"
#include "fdict.h"
#include "verbose.h"
using namespace std;
SpanFeatures::SpanFeatures(const string& param) :
kS(TD::Convert("S") * -1),
kX(TD::Convert("X") * -1),
use_collapsed_features_(false) {
string mapfile = param;
string valfile;
vector<string> toks;
Tokenize(param, ' ', &toks);
if (toks.size() == 2) { mapfile = toks[0]; valfile = toks[1]; }
if (mapfile.size() > 0) {
int lc = 0;
if (!SILENT) { cerr << "Reading word map for SpanFeatures from " << param << endl; }
ReadFile rf(mapfile);
istream& in = *rf.stream();
string line;
vector<WordID> v;
while(in) {
++lc;
getline(in, line);
if (line.empty()) continue;
v.clear();
TD::ConvertSentence(line, &v);
if (v.size() != 2) {
cerr << "Error reading line " << lc << ": " << line << endl;
abort();
}
word2class_[v[0]] = v[1];
}
word2class_[TD::Convert("<s>")] = TD::Convert("BOS");
word2class_[TD::Convert("</s>")] = TD::Convert("EOS");
oov_ = TD::Convert("OOV");
}
if (valfile.size() > 0) {
use_collapsed_features_ = true;
fid_beg_ = FD::Convert("SpanBegin");
fid_end_ = FD::Convert("SpanEnd");
fid_span_s_ = FD::Convert("SSpanContext");
fid_span_ = FD::Convert("XSpanContext");
ReadFile rf(valfile);
if (!SILENT) { cerr << " Loading span scores from " << valfile << endl; }
istream& in = *rf.stream();
string line;
while(in) {
getline(in, line);
if (line.size() == 0 || line[0] == '#') { continue; }
istringstream in(line);
string feat_name;
double weight;
in >> feat_name >> weight;
feat2val_[feat_name] = weight;
}
}
}
void SpanFeatures::TraversalFeaturesImpl(const SentenceMetadata& smeta,
const Hypergraph::Edge& edge,
const vector<const void*>& ant_contexts,
SparseVector<double>* features,
SparseVector<double>* estimated_features,
void* context) const {
assert(edge.j_ < end_span_ids_.size());
assert(edge.j_ >= 0);
assert(edge.i_ < beg_span_ids_.size());
assert(edge.i_ >= 0);
if (use_collapsed_features_) {
features->set_value(fid_end_, end_span_vals_[edge.j_]);
features->set_value(fid_beg_, beg_span_vals_[edge.i_]);
if (edge.rule_->lhs_ == kS)
features->set_value(fid_span_s_, span_vals_(edge.i_,edge.j_).second);
else
features->set_value(fid_span_, span_vals_(edge.i_,edge.j_).first);
} else { // non-collapsed features:
features->set_value(end_span_ids_[edge.j_], 1);
features->set_value(beg_span_ids_[edge.i_], 1);
if (edge.rule_->lhs_ == kS)
features->set_value(span_feats_(edge.i_,edge.j_).second, 1);
else
features->set_value(span_feats_(edge.i_,edge.j_).first, 1);
}
}
WordID SpanFeatures::MapIfNecessary(const WordID& w) const {
if (word2class_.empty()) return w;
map<WordID,WordID>::const_iterator it = word2class_.find(w);
if (it == word2class_.end()) return oov_;
return it->second;
}
void SpanFeatures::PrepareForInput(const SentenceMetadata& smeta) {
const Lattice& lattice = smeta.GetSourceLattice();
const WordID eos = TD::Convert("</s>");
const WordID bos = TD::Convert("<s>");
beg_span_ids_.resize(lattice.size() + 1);
end_span_ids_.resize(lattice.size() + 1);
span_feats_.resize(lattice.size() + 1, lattice.size() + 1);
if (use_collapsed_features_) {
beg_span_vals_.resize(lattice.size() + 1);
end_span_vals_.resize(lattice.size() + 1);
span_vals_.resize(lattice.size() + 1, lattice.size() + 1);
}
for (int i = 0; i <= lattice.size(); ++i) {
WordID word = eos;
WordID bword = bos;
if (i > 0)
bword = lattice[i-1][0].label;
bword = MapIfNecessary(bword);
if (i < lattice.size())
word = lattice[i][0].label; // rather arbitrary for lattices
word = MapIfNecessary(word);
ostringstream sfid;
sfid << "ES:" << TD::Convert(word);
end_span_ids_[i] = FD::Convert(sfid.str());
ostringstream bfid;
bfid << "BS:" << TD::Convert(bword);
beg_span_ids_[i] = FD::Convert(bfid.str());
if (use_collapsed_features_) {
end_span_vals_[i] = feat2val_[sfid.str()];
beg_span_vals_[i] = feat2val_[bfid.str()];
}
}
for (int i = 0; i <= lattice.size(); ++i) {
WordID bword = bos;
if (i > 0)
bword = lattice[i-1][0].label;
bword = MapIfNecessary(bword);
for (int j = 0; j <= lattice.size(); ++j) {
WordID word = eos;
if (j < lattice.size())
word = lattice[j][0].label;
word = MapIfNecessary(word);
ostringstream pf;
pf << "SS:" << TD::Convert(bword) << "_" << TD::Convert(word);
span_feats_(i,j).first = FD::Convert(pf.str());
span_feats_(i,j).second = FD::Convert("S_" + pf.str());
if (use_collapsed_features_) {
span_vals_(i,j).first = feat2val_[pf.str()];
span_vals_(i,j).second = feat2val_["S_" + pf.str()];
}
}
}
}
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