/*
* 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/*
* NominalToString.java
* Copyright (C) 2007 University of Waikato, Hamilton, New Zealand
*
*/
package weka.filters.unsupervised.attribute;
import weka.core.Attribute;
import weka.core.Capabilities;
import weka.core.FastVector;
import weka.core.Instance;
import weka.core.Instances;
import weka.core.Option;
import weka.core.OptionHandler;
import weka.core.RevisionUtils;
import weka.core.SingleIndex;
import weka.core.Range;
import weka.core.UnsupportedAttributeTypeException;
import weka.core.Utils;
import weka.core.Capabilities.Capability;
import weka.filters.Filter;
import weka.filters.UnsupervisedFilter;
import java.util.Enumeration;
import java.util.Vector;
/**
<!-- globalinfo-start -->
* Converts a nominal attribute (i.e. set number of values) to string (i.e. unspecified number of values).
* <p/>
<!-- globalinfo-end -->
*
<!-- options-start -->
* Valid options are: <p/>
*
* <pre> -C <col>
* Sets the range of attributes to convert (default last).</pre>
*
<!-- options-end -->
*
* @author FracPete (fracpete at waikato dot ac dot nz)
* @version $Revision: 1.6 $
*/
public class NominalToString
extends Filter
implements UnsupervisedFilter, OptionHandler {
/** for serialization */
static final long serialVersionUID = 8655492378380068939L;
/** The attribute's index setting. */
private Range m_AttIndex = new Range("last");
/**
* Returns a string describing this filter
*
* @return a description of the filter suitable for
* displaying in the explorer/experimenter gui
*/
public String globalInfo() {
return
"Converts a nominal attribute (i.e. set number of values) to string "
+ "(i.e. unspecified number of values).";
}
/**
* Returns the Capabilities of this filter.
*
* @return the capabilities of this object
* @see Capabilities
*/
public Capabilities getCapabilities() {
Capabilities result = super.getCapabilities();
// attributes
result.enableAllAttributes();
result.enable(Capability.MISSING_VALUES);
// class
result.enableAllClasses();
result.enable(Capability.MISSING_CLASS_VALUES);
result.enable(Capability.NO_CLASS);
return result;
}
/**
* Sets the format of the input instances.
*
* @param instanceInfo an Instances object containing the input
* instance structure (any instances contained
* in the object are ignored - only the
* structure is required).
* @return true if the outputFormat may be collected
* immediately.
* @throws UnsupportedAttributeTypeException if the selected attribute
* a string attribute.
* @throws Exception if the input format can't be set
* successfully.
*/
public boolean setInputFormat(Instances instanceInfo) throws Exception {
super.setInputFormat(instanceInfo);
m_AttIndex.setUpper(instanceInfo.numAttributes() - 1);
/* if (!instanceInfo.attribute(m_AttIndex.getIndex()).isNominal())
throw new UnsupportedAttributeTypeException("Chosen attribute is not of "
+ "type nominal."); */
return false;
}
/**
* Input an instance for filtering. The instance is processed
* and made available for output immediately.
*
* @param instance the input instance.
* @return true if the filtered instance may now be
* collected with output().
* @throws IllegalStateException if no input structure has been defined.
*/
public boolean input(Instance instance) {
if (getInputFormat() == null)
throw new IllegalStateException("No input instance format defined");
if (m_NewBatch) {
resetQueue();
m_NewBatch = false;
}
if (isOutputFormatDefined()) {
Instance newInstance = (Instance) instance.copy();
push(newInstance);
return true;
}
bufferInput(instance);
return false;
}
/**
* Signifies that this batch of input to the filter is finished. If the
* filter requires all instances prior to filtering, output() may now
* be called to retrieve the filtered instances.
*
* @return true if there are instances pending output.
* @throws IllegalStateException if no input structure has been defined.
*/
public boolean batchFinished() {
if (getInputFormat() == null)
throw new IllegalStateException("No input instance format defined");
if (!isOutputFormatDefined()) {
setOutputFormat();
// Convert pending input instances
for(int i = 0; i < getInputFormat().numInstances(); i++)
push((Instance) getInputFormat().instance(i).copy());
}
flushInput();
m_NewBatch = true;
return (numPendingOutput() != 0);
}
/**
* Returns an enumeration describing the available options.
*
* @return an enumeration of all the available options.
*/
public Enumeration listOptions() {
Vector result = new Vector();
result.addElement(new Option(
"\tSets the range of attributes to convert (default last).",
"C", 1, "-C <col>"));
return result.elements();
}
/**
* Parses a given list of options. <p/>
*
<!-- options-start -->
* Valid options are: <p/>
*
* <pre> -C <col>
* Sets the range of attributes to convert (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;
tmpStr = Utils.getOption('C', options);
if (tmpStr.length() != 0)
setAttributeIndexes(tmpStr);
else
setAttributeIndexes("last");
if (getInputFormat() != null)
setInputFormat(getInputFormat());
}
/**
* Gets the current settings of the filter.
*
* @return an array of strings suitable for passing to setOptions
*/
public String[] getOptions() {
Vector result;
result = new Vector();
result.add("-C");
result.add("" + (getAttributeIndexes()));
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 attributeIndexesTipText() {
return "Sets a range attributes to process. Any non-nominal "
+ "attributes in the range are left untouched (\"first\" and \"last\" are valid values)";
}
/**
* Get the index of the attribute used.
*
* @return the index of the attribute
*/
public String getAttributeIndexes() {
// return m_AttIndex.getSingleIndex();
return m_AttIndex.getRanges();
}
/**
* Sets index of the attribute used.
*
* @param attIndex the index of the attribute
*/
public void setAttributeIndexes(String attIndex) {
// m_AttIndex.setSingleIndex(attIndex);
m_AttIndex.setRanges(attIndex);
}
/**
* Set the output format. Takes the current average class values
* and m_InputFormat and calls setOutputFormat(Instances)
* appropriately.
*/
private void setOutputFormat() {
Instances newData;
FastVector newAtts;
// Compute new attributes
newAtts = new FastVector(getInputFormat().numAttributes());
for (int j = 0; j < getInputFormat().numAttributes(); j++) {
Attribute att = getInputFormat().attribute(j);
if (!att.isNominal() || !m_AttIndex.isInRange(j))
newAtts.addElement(att);
else
newAtts.addElement(new Attribute(att.name(), (FastVector) null));
}
// Construct new header
newData = new Instances(getInputFormat().relationName(), newAtts, 0);
newData.setClassIndex(getInputFormat().classIndex());
setOutputFormat(newData);
}
/**
* Returns the revision string.
*
* @return the revision
*/
public String getRevision() {
return RevisionUtils.extract("$Revision: 1.6 $");
}
/**
* Main method for testing this class.
*
* @param args should contain arguments to the filter: use -h for help
*/
public static void main(String [] args) {
runFilter(new NominalToString(), args);
}
}