mosesdecoder/mert/Data.cpp
2012-02-20 08:29:53 +09:00

271 lines
7.0 KiB
C++

/*
* Data.cpp
* mert - Minimum Error Rate Training
*
* Created by Nicola Bertoldi on 13/05/08.
*
*/
#include <algorithm>
#include "util/check.hh"
#include <cmath>
#include <fstream>
#include "Data.h"
#include "FileStream.h"
#include "Scorer.h"
#include "ScorerFactory.h"
#include "Util.h"
Data::Data()
: theScorer(NULL),
number_of_scores(0),
_sparse_flag(false),
scoredata(),
featdata() {}
Data::Data(Scorer& ptr)
: theScorer(&ptr),
score_type(theScorer->getName()),
number_of_scores(0),
_sparse_flag(false),
scoredata(new ScoreData(*theScorer)),
featdata(new FeatureData)
{
TRACE_ERR("Data::score_type " << score_type << std::endl);
TRACE_ERR("Data::Scorer type from Scorer: " << theScorer->getName() << endl);
}
//ADDED BY TS
void Data::remove_duplicates() {
size_t nSentences = featdata->size();
assert(scoredata->size() == nSentences);
for (size_t s=0; s < nSentences; s++) {
FeatureArray& feat_array = featdata->get(s);
ScoreArray& score_array = scoredata->get(s);
assert(feat_array.size() == score_array.size());
//serves as a hash-map:
std::map<double, std::vector<size_t> > lookup;
size_t end_pos = feat_array.size() - 1;
size_t nRemoved = 0;
for (size_t k=0; k <= end_pos; k++) {
const FeatureStats& cur_feats = feat_array.get(k);
double sum = 0.0;
for (size_t l=0; l < cur_feats.size(); l++)
sum += cur_feats.get(l);
if (lookup.find(sum) != lookup.end()) {
//std::cerr << "hit" << std::endl;
std::vector<size_t>& cur_list = lookup[sum];
size_t l=0;
for (l=0; l < cur_list.size(); l++) {
size_t j=cur_list[l];
if (cur_feats == feat_array.get(j)
&& score_array.get(k) == score_array.get(j)) {
if (k < end_pos) {
feat_array.swap(k,end_pos);
score_array.swap(k,end_pos);
k--;
}
end_pos--;
nRemoved++;
break;
}
}
if (l == lookup[sum].size())
cur_list.push_back(k);
}
else
lookup[sum].push_back(k);
// for (size_t j=0; j < k; j++) {
// if (feat_array.get(k) == feat_array.get(j)
// && score_array.get(k) == score_array.get(j)) {
// if (k < end_pos) {
// feat_array.swap(k,end_pos);
// score_array.swap(k,end_pos);
// k--;
// }
// end_pos--;
// nRemoved++;
// break;
// }
// }
}
if (nRemoved > 0) {
feat_array.resize(end_pos+1);
score_array.resize(end_pos+1);
}
}
}
//END_ADDED
void Data::loadnbest(const std::string &file)
{
TRACE_ERR("loading nbest from " << file << std::endl);
FeatureStats featentry;
ScoreStats scoreentry;
std::string sentence_index;
inputfilestream inp(file); // matches a stream with a file. Opens the file
if (!inp.good())
throw runtime_error("Unable to open: " + file);
std::string substring, subsubstring, stringBuf;
std::string theSentence;
std::string::size_type loc;
while (getline(inp,stringBuf,'\n')) {
if (stringBuf.empty()) continue;
// TRACE_ERR("stringBuf: " << stringBuf << std::endl);
getNextPound(stringBuf, substring, "|||"); //first field
sentence_index = substring;
getNextPound(stringBuf, substring, "|||"); //second field
theSentence = substring;
// adding statistics for error measures
featentry.reset();
scoreentry.clear();
theScorer->prepareStats(sentence_index, theSentence, scoreentry);
scoredata->add(scoreentry, sentence_index);
getNextPound(stringBuf, substring, "|||"); //third field
// examine first line for name of features
if (!existsFeatureNames()) {
std::string stringsupport=substring;
std::string features="";
std::string tmpname="";
size_t tmpidx=0;
while (!stringsupport.empty()) {
// TRACE_ERR("Decompounding: " << substring << std::endl);
getNextPound(stringsupport, subsubstring);
// string ending with ":" are skipped, because they are the names of the features
if ((loc = subsubstring.find_last_of(":")) != subsubstring.length()-1) {
features+=tmpname+"_"+stringify(tmpidx)+" ";
tmpidx++;
}
// ignore sparse feature name
else if (subsubstring.find("_") != string::npos) {
// also ignore its value
getNextPound(stringsupport, subsubstring);
}
// update current feature name
else {
tmpidx=0;
tmpname=subsubstring.substr(0,subsubstring.size() - 1);
}
}
featdata->setFeatureMap(features);
}
// adding features
while (!substring.empty()) {
// TRACE_ERR("Decompounding: " << substring << std::endl);
getNextPound(substring, subsubstring);
// no ':' -> feature value that needs to be stored
if ((loc = subsubstring.find_last_of(":")) != subsubstring.length()-1) {
featentry.add(ConvertStringToFeatureStatsType(subsubstring));
}
// sparse feature name? store as well
else if (subsubstring.find("_") != string::npos) {
std::string name = subsubstring;
getNextPound(substring, subsubstring);
featentry.addSparse( name, atof(subsubstring.c_str()) );
_sparse_flag = true;
}
}
//cerr << "number of sparse features: " << featentry.getSparse().size() << endl;
featdata->add(featentry,sentence_index);
}
inp.close();
}
// TODO
void Data::mergeSparseFeatures() {
std::cerr << "ERROR: sparse features can only be trained with pairwise ranked optimizer (PRO), not traditional MERT\n";
exit(1);
}
void Data::createShards(size_t shard_count, float shard_size, const string& scorerconfig,
std::vector<Data>& shards)
{
CHECK(shard_count);
CHECK(shard_size >= 0);
CHECK(shard_size <= 1);
size_t data_size = scoredata->size();
CHECK(data_size == featdata->size());
shard_size *= data_size;
for (size_t shard_id = 0; shard_id < shard_count; ++shard_id) {
vector<size_t> shard_contents;
if (shard_size == 0) {
//split into roughly equal size shards
const size_t shard_start = floor(0.5 + shard_id * static_cast<float>(data_size) / shard_count);
const size_t shard_end = floor(0.5 + (shard_id + 1) * static_cast<float>(data_size) / shard_count);
for (size_t i = shard_start; i < shard_end; ++i) {
shard_contents.push_back(i);
}
} else {
//create shards by randomly sampling
for (size_t i = 0; i < floor(shard_size+0.5); ++i) {
shard_contents.push_back(rand() % data_size);
}
}
Scorer* scorer = ScorerFactory::getScorer(score_type, scorerconfig);
shards.push_back(Data(*scorer));
shards.back().score_type = score_type;
shards.back().number_of_scores = number_of_scores;
shards.back()._sparse_flag = _sparse_flag;
for (size_t i = 0; i < shard_contents.size(); ++i) {
shards.back().featdata->add(featdata->get(shard_contents[i]));
shards.back().scoredata->add(scoredata->get(shard_contents[i]));
}
//cerr << endl;
}
}