void recommender_base::complete_row(const sfv_t& query, sfv_t& ret) const {
ret.clear();
vector<pair<string, float> > ids;
similar_row(query, ids, complete_row_similar_num_);
if (ids.size() == 0) {
return;
}
size_t exist_row_num = 0;
for (size_t i = 0; i < ids.size(); ++i) {
sfv_t row;
orig_.get_row(ids[i].first, row);
if (row.size() == 0) {
continue;
} else {
++exist_row_num;
}
float ratio = ids[i].second;
for (size_t j = 0; j < row.size(); ++j) {
ret.push_back(make_pair(row[j].first, row[j].second * ratio));
}
}
if (exist_row_num == 0) {
return;
}
sort_and_merge(ret);
for (size_t i = 0; i < ret.size(); ++i) {
ret[i].second /= exist_row_num;
}
}
void add_feature(const std::string& key, double value, sfv_t& ret_fv) const {
ret_fv.push_back(make_pair(key, std::log(std::max(1.0, value))));
}
void add_feature(const std::string& key, double value, sfv_t& ret_fv) const {
std::stringstream ss;
ss << key << "$" << value;
ret_fv.push_back(make_pair(ss.str(), 1.0));
}