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/** @file simpleexpand.cc
* @brief Simple example program demonstrating query expansion.
*/
/* Copyright (C) 2007,2010,2015 Olly Betts
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <xapian.h>
#include <iostream>
#include <string>
#include <cstdlib> // For exit().
#include <cstring>
using namespace std;
int
main(int argc, char **argv)
try {
// We require at least two command line arguments.
if (argc < 3) {
int rc = 1;
if (argv[1]) {
if (strcmp(argv[1], "--version") == 0) {
cout << "simpleexpand" << endl;
exit(0);
}
if (strcmp(argv[1], "--help") == 0) {
rc = 0;
}
}
cout << "Usage: " << argv[0] << " PATH_TO_DATABASE QUERY [-- [DOCID...]]" << endl;
exit(rc);
}
// Open the database for searching.
Xapian::Database db(argv[1]);
// Start an enquire session.
Xapian::Enquire enquire(db);
// Combine command line arguments up to "--" with spaces between
// them, so that simple queries don't have to be quoted at the shell
// level.
string query_string(argv[2]);
argv += 3;
while (*argv && strcmp(*argv, "--") != 0) {
query_string += ' ';
query_string += *argv++;
}
// Create an RSet with the listed docids in.
Xapian::RSet rset;
if (*argv) {
while (*++argv) {
rset.add_document(atoi(*argv));
}
}
// Parse the query string to produce a Xapian::Query object.
Xapian::QueryParser qp;
Xapian::Stem stemmer("english");
qp.set_stemmer(stemmer);
qp.set_database(db);
qp.set_stemming_strategy(Xapian::QueryParser::STEM_SOME);
Xapian::Query query = qp.parse_query(query_string);
cout << "Parsed query is: " << query.get_description() << endl;
// Find the top 10 results for the query.
enquire.set_query(query);
Xapian::MSet matches = enquire.get_mset(0, 10, &rset);
// Display the results.
cout << matches.get_matches_estimated() << " results found:" << endl;
for (Xapian::MSetIterator i = matches.begin(); i != matches.end(); ++i) {
cout << i.get_rank() + 1 << ": " << i.get_weight() << " docid=" << *i
<< " [" << i.get_document().get_data() << "]\n\n";
}
// If no relevant docids were given, invent an RSet containing the top 5
// matches (or all the matches if there are less than 5).
if (rset.empty()) {
int c = 5;
Xapian::MSetIterator i = matches.begin();
while (c-- && i != matches.end()) {
rset.add_document(*i);
++i;
}
}
// Generate an ESet containing terms that the user might want to add to
// the query.
Xapian::ESet eset = enquire.get_eset(10, rset);
// List the terms.
Xapian::ESetIterator t;
for (t = eset.begin(); t != eset.end(); ++t) {
cout << *t << ": weight = " << t.get_weight() << endl;
}
} catch (const Xapian::Error &e) {
cout << e.get_description() << endl;
exit(1);
}
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