/**
* Prints the results
*
* @param pw PrintWriter the file to write the results to.
* @param q SearchRequest the search request to get results from.
*/
public void printResults(PrintWriter pw, SearchRequest q) throws IOException {
ResultSet set = q.getResultSet();
int[] docids = set.getDocids();
double[] scores = set.getScores();
int minimum = RESULTS_LENGTH;
// if the minimum number of documents is more than the
// number of documents in the results, aw.length, then
// set minimum = aw.length
if (minimum > set.getResultSize()) minimum = set.getResultSize();
if (verbose)
if (set.getResultSize() > 0)
pw.write("\n\tDisplaying 1-" + set.getResultSize() + " results\n");
else pw.write("\n\tNo results\n");
if (set.getResultSize() == 0) return;
int metaKeyId = 0;
final int metaKeyCount = metaKeys.length;
String[][] docNames = new String[metaKeyCount][];
for (String metaIndexDocumentKey : metaKeys) {
if (set.hasMetaItems(metaIndexDocumentKey)) {
docNames[metaKeyId] = set.getMetaItems(metaIndexDocumentKey);
} else {
final MetaIndex metaIndex = index.getMetaIndex();
docNames[metaKeyId] = metaIndex.getItems(metaIndexDocumentKey, docids);
}
metaKeyId++;
}
StringBuilder sbuffer = new StringBuilder();
// the results are ordered in asceding order
// with respect to the score. For example, the
// document with the highest score has score
// score[scores.length-1] and its docid is
// docid[docids.length-1].
int start = 0;
int end = minimum;
for (int i = start; i < end; i++) {
if (scores[i] <= 0d) continue;
sbuffer.append(i);
sbuffer.append(" ");
for (metaKeyId = 0; metaKeyId < metaKeyCount; metaKeyId++) {
sbuffer.append(docNames[metaKeyId][i]);
sbuffer.append(" ");
}
sbuffer.append(docids[i]);
sbuffer.append(" ");
sbuffer.append(scores[i]);
sbuffer.append('\n');
}
// System.out.println(sbuffer.toString());
pw.write(sbuffer.toString());
pw.flush();
// pw.write("finished outputting\n");
}
/** method which extracts the docnos for the prescribed resultset */
protected String[] obtainDocnos(
final String metaIndexDocumentKey, final SearchRequest q, final ResultSet set)
throws IOException {
String[] docnos;
if (set.hasMetaItems(metaIndexDocumentKey)) {
docnos = set.getMetaItems(metaIndexDocumentKey);
} else {
final MetaIndex metaIndex = index.getMetaIndex();
docnos = metaIndex.getItems(metaIndexDocumentKey, set.getDocids());
}
return docnos;
}
/**
* Runs the actual query expansion
*
* @see
* org.terrier.querying.PostProcess#process(org.terrier.querying.Manager,org.terrier.querying.SearchRequest)
*/
public void process(Manager manager, SearchRequest q) {
Index index = getIndex(manager);
lastIndex = index;
documentIndex = index.getDocumentIndex();
invertedIndex = index.getInvertedIndex();
lexicon = index.getLexicon();
collStats = index.getCollectionStatistics();
directIndex = index.getDirectIndex();
metaIndex = index.getMetaIndex();
if (directIndex == null) {
logger.error("This index does not have a direct index. Query expansion disabled!!");
return;
}
logger.debug("Starting query expansion post-processing.");
// get the query expansion model to use
String qeModel = q.getControl("qemodel");
if (qeModel == null || qeModel.length() == 0) {
logger.warn(
"qemodel control not set for QueryExpansion" + " post process. Using default model Bo1");
qeModel = "Bo1";
}
setQueryExpansionModel(getQueryExpansionModel(qeModel));
if (logger.isDebugEnabled()) {
logger.info("query expansion model: " + QEModel.getInfo());
}
MatchingQueryTerms queryTerms = ((Request) q).getMatchingQueryTerms();
if (queryTerms == null) {
logger.warn("No query terms for this query. Skipping QE");
return;
}
// get the expanded query terms
try {
expandQuery(queryTerms, (Request) q);
} catch (IOException ioe) {
logger.error("IOException while expanding query, skipping QE", ioe);
return;
}
if (logger.isDebugEnabled()) {
logger.info("query length after expansion: " + queryTerms.length());
logger.info("Expanded query: ");
}
final String[] newQueryTerms = queryTerms.getTerms();
StringBuilder newQuery = new StringBuilder();
for (int i = 0; i < newQueryTerms.length; i++) {
try {
if (logger.isDebugEnabled()) {
logger.info(
(i + 1)
+ ": "
+ newQueryTerms[i]
+ ", normalisedFrequency: "
+ Rounding.toString(queryTerms.getTermWeight(newQueryTerms[i]), 4));
}
newQuery.append(newQueryTerms[i]);
newQuery.append('^');
newQuery.append(Rounding.toString(queryTerms.getTermWeight(newQueryTerms[i]), 9));
newQuery.append(' ');
} catch (NullPointerException npe) {
logger.error("Nullpointer exception occured in Query Expansion dumping of new Query", npe);
}
}
logger.debug("NEWQUERY " + q.getQueryID() + " " + newQuery.toString());
lastExpandedQuery = newQuery.toString();
q.setControl("QE.ExpandedQuery", newQuery.toString());
final boolean no2ndPass =
Boolean.parseBoolean(ApplicationSetup.getProperty("qe.no.2nd.matching", "false"));
if (no2ndPass) {
return;
}
// run retrieval process again for the expanded query
logger.info("Accessing inverted file for expanded query " + q.getQueryID());
manager.runMatching(q);
}
public void readIndex() throws IOException {
index = terrierIndexFactory.readIndex(indexId, language);
documentIndex = index.getDocumentIndex();
metaIndex = index.getMetaIndex();
}
/** {@inheritDoc} */
public void setIndex(Index index) {
metaIndex = index.getMetaIndex();
}