package de.lmu.ifi.dbs.elki.datasource.parser;
/*
This file is part of ELKI:
Environment for Developing KDD-Applications Supported by Index-Structures
Copyright (C) 2011
Ludwig-Maximilians-Universität München
Lehr- und Forschungseinheit für Datenbanksysteme
ELKI Development Team
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as published by
the Free Software Foundation, either version 3 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 Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.BitSet;
import java.util.List;
import java.util.regex.Pattern;
import de.lmu.ifi.dbs.elki.data.Bit;
import de.lmu.ifi.dbs.elki.data.BitVector;
import de.lmu.ifi.dbs.elki.data.LabelList;
import de.lmu.ifi.dbs.elki.data.type.TypeUtil;
import de.lmu.ifi.dbs.elki.data.type.VectorFieldTypeInformation;
import de.lmu.ifi.dbs.elki.datasource.bundle.MultipleObjectsBundle;
import de.lmu.ifi.dbs.elki.logging.Logging;
import de.lmu.ifi.dbs.elki.utilities.documentation.Description;
import de.lmu.ifi.dbs.elki.utilities.documentation.Title;
/**
* Provides a parser for parsing one BitVector per line, bits separated by
* whitespace.
* <p/>
* Several labels may be given per BitVector. A label must not be parseable as
* Bit. Lines starting with "#" will be ignored.
*
* @author Arthur Zimek
*
* @apiviz.has BitVector
*/
@Title("Bit Vector Label Parser")
@Description("Parses the following format of lines:\n" + "A single line provides a single BitVector. Bits are separated by whitespace. Any substring not containing whitespace is tried to be read as Bit. If this fails, it will be appended to a label. (Thus, any label must not be parseable as Bit.) Empty lines and lines beginning with \"#\" will be ignored. If any BitVector differs in its dimensionality from other BitVectors, the parse method will fail with an Exception.")
public class BitVectorLabelParser extends AbstractParser implements Parser {
/**
* Class logger
*/
private static final Logging logger = Logging.getLogger(BitVectorLabelParser.class);
/**
* Constructor.
*
* @param colSep
* @param quoteChar
*/
public BitVectorLabelParser(Pattern colSep, char quoteChar) {
super(colSep, quoteChar);
}
@Override
public MultipleObjectsBundle parse(InputStream in) {
BufferedReader reader = new BufferedReader(new InputStreamReader(in));
int lineNumber = 0;
int dimensionality = -1;
List<BitVector> vectors = new ArrayList<BitVector>();
List<LabelList> labels = new ArrayList<LabelList>();
try {
for(String line; (line = reader.readLine()) != null; lineNumber++) {
if(!line.startsWith(COMMENT) && line.length() > 0) {
List<String> entries = tokenize(line);
// TODO: use more efficient storage right away?
List<Bit> attributes = new ArrayList<Bit>();
LabelList ll = new LabelList();
for(String entry : entries) {
try {
Bit attribute = Bit.valueOf(entry);
attributes.add(attribute);
}
catch(NumberFormatException e) {
ll.add(entry);
}
}
if(dimensionality < 0) {
dimensionality = attributes.size();
}
else if(dimensionality != attributes.size()) {
throw new IllegalArgumentException("Differing dimensionality in line " + lineNumber + ".");
}
vectors.add(new BitVector(attributes.toArray(new Bit[attributes.size()])));
labels.add(ll);
}
}
}
catch(IOException e) {
throw new IllegalArgumentException("Error while parsing line " + lineNumber + ".");
}
return MultipleObjectsBundle.makeSimple(getTypeInformation(dimensionality), vectors, TypeUtil.LABELLIST, labels);
}
protected VectorFieldTypeInformation<BitVector> getTypeInformation(int dimensionality) {
return new VectorFieldTypeInformation<BitVector>(BitVector.class, dimensionality, new BitVector(new BitSet(), dimensionality));
}
@Override
protected Logging getLogger() {
return logger;
}
/**
* Parameterization class.
*
* @author Erich Schubert
*
* @apiviz.exclude
*/
public static class Parameterizer extends AbstractParser.Parameterizer {
@Override
protected BitVectorLabelParser makeInstance() {
return new BitVectorLabelParser(colSep, quoteChar);
}
}
}