/*
* 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.
*/
/*
* Remove.java
* Copyright (C) 1999 Len Trigg
*
*/
package weka.filters.unsupervised.attribute;
import weka.filters.*;
import java.io.*;
import java.util.*;
import weka.core.*;
/**
* An instance filter that deletes a range of attributes from the dataset.<p>
*
* Valid filter-specific options are:<p>
*
* -R index1,index2-index4,...<br>
* Specify list of columns to delete. First and last are valid indexes.
* (default none)<p>
*
* -V<br>
* Invert matching sense (i.e. only keep specified columns)<p>
*
* @author Len Trigg (trigg@cs.waikato.ac.nz)
* @version $Revision: 1.1.1.1 $
*/
public class Remove extends Filter
implements UnsupervisedFilter, StreamableFilter, OptionHandler {
/** Stores which columns to select as a funky range */
protected Range m_SelectCols = new Range();
/**
* Stores the indexes of the selected attributes in order, once the
* dataset is seen
*/
protected int [] m_SelectedAttributes;
/**
* Contains an index of string attributes in the input format
* that will survive the filtering process
*/
protected int [] m_InputStringIndex;
/**
* Returns an enumeration describing the available options.
*
* @return an enumeration of all the available options.
*/
public Enumeration listOptions() {
Vector newVector = new Vector(2);
newVector.addElement(new Option(
"\tSpecify list of columns to delete. First and last are valid\n"
+"\tindexes. (default none)",
"R", 1, "-R <index1,index2-index4,...>"));
newVector.addElement(new Option(
"\tInvert matching sense (i.e. only keep specified columns)",
"V", 0, "-V"));
return newVector.elements();
}
/**
* Parses a given list of options controlling the behaviour of this object.
* Valid options are:<p>
*
* -R index1,index2-index4,...<br>
* Specify list of columns to delete. First and last are valid indexes.
* (default none)<p>
*
* -V<br>
* Invert matching sense (i.e. only keep specified columns)<p>
*
* @param options the list of options as an array of strings
* @exception Exception if an option is not supported
*/
public void setOptions(String[] options) throws Exception {
String deleteList = Utils.getOption('R', options);
if (deleteList.length() != 0) {
setAttributeIndices(deleteList);
}
setInvertSelection(Utils.getFlag('V', options));
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() {
String [] options = new String [3];
int current = 0;
if (getInvertSelection()) {
options[current++] = "-V";
}
if (!getAttributeIndices().equals("")) {
options[current++] = "-R"; options[current++] = getAttributeIndices();
}
while (current < options.length) {
options[current++] = "";
}
return options;
}
/**
* 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
* @exception Exception if the format couldn't be set successfully
*/
public boolean setInputFormat(Instances instanceInfo)throws Exception{
super.setInputFormat(instanceInfo);
m_SelectCols.setUpper(instanceInfo.numAttributes() - 1);
FastVector attributes=new FastVector();
int inputClass=instanceInfo.classIndex(),outputClass=-1;
m_SelectedAttributes=m_SelectCols.getSelection();
int inStrKeepLen=0;
int[] inStrKeep=new int[m_SelectedAttributes.length];
for(int i=0;i<m_SelectedAttributes.length;i++){
int current = m_SelectedAttributes[i];
if(inputClass==current)outputClass=attributes.size();
Attribute keep=(Attribute)instanceInfo.attribute(current).copy();
if(keep.type()==Attribute.STRING)inStrKeep[inStrKeepLen++] = current;
attributes.addElement(keep);
}
m_InputStringIndex = new int[inStrKeepLen];
System.arraycopy(inStrKeep,0,m_InputStringIndex,0,inStrKeepLen);
Instances outputFormat=new Instances(instanceInfo.relationName(),attributes,0);
if(outputClass!=-1)outputFormat.setClassIndex(outputClass);
setOutputFormat(outputFormat);
return true;
}
/**
* Input an instance for filtering. Ordinarily the instance is processed
* and made available for output immediately. Some filters require all
* instances be read before producing output.
*
* @param instance the input instance
* @return true if the filtered instance may now be
* collected with output().
* @exception 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;
}
double [] vals = new double[getOutputFormat().numAttributes()];
for (int i = 0; i < m_SelectedAttributes.length; i++) {
int current = m_SelectedAttributes[i];
vals[i] = instance.value(current);
}
Instance inst = null;
if (instance instanceof SparseInstance) {
inst = new SparseInstance(instance.weight(), vals);
} else {
inst = new Instance(instance.weight(), vals);
}
copyStringValues(inst, false, instance.dataset(), m_InputStringIndex,
getOutputFormat(), getOutputStringIndex());
inst.setDataset(getOutputFormat());
push(inst);
return true;
}
/**
* Returns a string describing this filter
*
* @return a description of the filter suitable for
* displaying in the explorer/experimenter gui
*/
public String globalInfo() {
return "An instance filter that removes a range of"
+ " attributes from the dataset.";
}
/**
* Returns the tip text for this property
*
* @return tip text for this property suitable for
* displaying in the explorer/experimenter gui
*/
public String invertSelectionTipText() {
return "Determines whether action is to select or delete."
+ " If set to true, only the specified attributes will be kept;"
+ " If set to false, specified attributes will be deleted.";
}
/**
* Get whether the supplied columns are to be removed or kept
*
* @return true if the supplied columns will be kept
*/
public boolean getInvertSelection() {
return !m_SelectCols.getInvert();
}
/**
* Set whether selected columns should be removed or kept. If true the
* selected columns are kept and unselected columns are deleted. If false
* selected columns are deleted and unselected columns are kept.
*
* @param invert the new invert setting
*/
public void setInvertSelection(boolean invert) {
m_SelectCols.setInvert(!invert);
}
/**
* Returns the tip text for this property
*
* @return tip text for this property suitable for
* displaying in the explorer/experimenter gui
*/
public String attributeIndicesTipText() {
return "Specify range of attributes to act on."
+ " This is a comma separated list of attribute indices, with"
+ " \"first\" and \"last\" valid values. Specify an inclusive"
+ " range with \"-\". E.g: \"first-3,5,6-10,last\".";
}
/**
* Get the current range selection.
*
* @return a string containing a comma separated list of ranges
*/
public String getAttributeIndices() {
return m_SelectCols.getRanges();
}
/**
* Set which attributes are to be deleted (or kept if invert is true)
*
* @param rangeList a string representing the list of attributes. Since
* the string will typically come from a user, attributes are indexed from
* 1. <br>
* eg: first-3,5,6-last
*/
public void setAttributeIndices(String rangeList) {
m_SelectCols.setRanges(rangeList);
}
/**
* Set which attributes are to be deleted (or kept if invert is true)
*
* @param attributes an array containing indexes of attributes to select.
* Since the array will typically come from a program, attributes are indexed
* from 0.
*/
public void setAttributeIndicesArray(int [] attributes) {
setAttributeIndices(Range.indicesToRangeList(attributes));
}
/**
* Main method for testing this class.
*
* @param argv should contain arguments to the filter: use -h for help
*/
public static void main(String [] argv) {
try {
if (Utils.getFlag('b', argv)) {
Filter.batchFilterFile(new Remove(), argv);
} else {
Filter.filterFile(new Remove(), argv);
}
} catch (Exception ex) {
System.out.println(ex.getMessage());
}
}
}