/*
* 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 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/*
* ClassAssigner.java
* Copyright (C) 2006-2012 University of Waikato, Hamilton, New Zealand
*/
package weka.filters.unsupervised.attribute;
import java.util.Enumeration;
import java.util.Vector;
import weka.core.Capabilities;
import weka.core.Capabilities.Capability;
import weka.core.Instance;
import weka.core.Instances;
import weka.core.Option;
import weka.core.RevisionUtils;
import weka.core.Utils;
import weka.filters.SimpleStreamFilter;
/**
<!-- globalinfo-start -->
* Filter that can set and unset the class index.
* <p/>
<!-- globalinfo-end -->
*
<!-- options-start -->
* Valid options are: <p/>
*
* <pre> -D
* Turns on output of debugging information.</pre>
*
* <pre> -C <num|first|last|0>
* The index of the class attribute. Index starts with 1, 'first'
* and 'last' are accepted, '0' unsets the class index.
* (default: last)</pre>
*
<!-- options-end -->
*
* @author fracpete (fracpete at waikato dot ac dot nz)
* @version $Revision: 8034 $
*/
public class ClassAssigner
extends SimpleStreamFilter {
/** for serialization. */
private static final long serialVersionUID = 1775780193887394115L;
/** use the first attribute as class. */
public final static int FIRST = 0;
/** use the last attribute as class. */
public final static int LAST = -2;
/** unset the class attribute. */
public final static int UNSET = -1;
/** the class index. */
protected int m_ClassIndex = LAST;
/**
* Returns a string describing this classifier.
*
* @return a description of the classifier suitable for
* displaying in the explorer/experimenter gui
*/
public String globalInfo() {
return
"Filter that can set and unset the class index.";
}
/**
* Returns an enumeration describing the available options.
*
* @return an enumeration of all the available options.
*/
public Enumeration listOptions() {
Vector result = new Vector();
Enumeration enm = super.listOptions();
while (enm.hasMoreElements())
result.add(enm.nextElement());
result.addElement(new Option(
"\tThe index of the class attribute. Index starts with 1, 'first'\n"
+ "\tand 'last' are accepted, '0' unsets the class index.\n"
+ "\t(default: last)",
"C", 1, "-C <num|first|last|0>"));
return result.elements();
}
/**
* Parses a list of options for this object. <p/>
*
<!-- options-start -->
* Valid options are: <p/>
*
* <pre> -D
* Turns on output of debugging information.</pre>
*
* <pre> -C <num|first|last|0>
* The index of the class attribute. Index starts with 1, 'first'
* and 'last' are accepted, '0' unsets the class index.
* (default: last)</pre>
*
<!-- options-end -->
*
* @param options the list of options as an array of strings
* @throws Exception if an option is not supported
*/
public void setOptions(String[] options) throws Exception {
String tmpStr;
super.setOptions(options);
tmpStr = Utils.getOption("C", options);
if (tmpStr.length() != 0)
setClassIndex(tmpStr);
else
setClassIndex("last");
}
/**
* Gets the current settings of the filter.
*
* @return an array of strings suitable for passing to setOptions
*/
public String[] getOptions() {
Vector result;
String[] options;
int i;
result = new Vector();
options = super.getOptions();
for (i = 0; i < options.length; i++)
result.add(options[i]);
result.add("-C");
result.add(getClassIndex());
return (String[]) result.toArray(new String[result.size()]);
}
/**
* Returns the tip text for this property.
*
* @return tip text for this property suitable for
* displaying in the explorer/experimenter gui
*/
public String classIndexTipText() {
return
"The index of the class attribute, starts with 1, 'first' and 'last' "
+ "are accepted as well, '0' unsets the class index.";
}
/**
* sets the class index.
*
* @param value the class index
*/
public void setClassIndex(String value) {
if (value.equalsIgnoreCase("first")) {
m_ClassIndex = FIRST;
}
else if (value.equalsIgnoreCase("last")) {
m_ClassIndex = LAST;
}
else if (value.equalsIgnoreCase("0")) {
m_ClassIndex = UNSET;
}
else {
try {
m_ClassIndex = Integer.parseInt(value) - 1;
}
catch (Exception e) {
System.err.println("Error parsing '" + value + "'!");
}
}
}
/**
* returns the class index.
*
* @return the class index
*/
public String getClassIndex() {
if (m_ClassIndex == FIRST)
return "first";
else if (m_ClassIndex == LAST)
return "last";
else if (m_ClassIndex == UNSET)
return "0";
else
return "" + (m_ClassIndex + 1);
}
/**
* Returns the Capabilities of this filter.
*
* @return the capabilities of this object
* @see Capabilities
*/
public Capabilities getCapabilities() {
Capabilities result = super.getCapabilities();
result.disableAll();
// attributes
result.enableAllAttributes();
result.enable(Capability.MISSING_VALUES);
// class
result.enableAllClasses();
result.enable(Capability.NO_CLASS);
result.enable(Capability.MISSING_CLASS_VALUES);
return result;
}
/**
* Determines the output format based on the input format and returns
* this.
*
* @param inputFormat the input format to base the output format on
* @return the output format
* @throws Exception in case the class index is invalid
*/
protected Instances determineOutputFormat(Instances inputFormat)
throws Exception {
Instances result = new Instances(inputFormat, 0);
if (m_ClassIndex == FIRST)
result.setClassIndex(0);
else if (m_ClassIndex == LAST)
result.setClassIndex(result.numAttributes() - 1);
else if (m_ClassIndex == UNSET)
result.setClassIndex(-1);
else
result.setClassIndex(m_ClassIndex);
return result;
}
/**
* processes the given instance (may change the provided instance) and
* returns the modified version.
*
* @param instance the instance to process
* @return the modified data
* @throws Exception in case the processing goes wrong
*/
protected Instance process(Instance instance) throws Exception {
return instance;
}
/**
* Returns the revision string.
*
* @return the revision
*/
public String getRevision() {
return RevisionUtils.extract("$Revision: 8034 $");
}
/**
* Main method for executing this class.
*
* @param args should contain arguments for the filter: use -h for help
*/
public static void main(String[] args) {
runFilter(new ClassAssigner(), args);
}
}