content: /*
   *    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.
   */
  
  /*
   *    NominalToBinary.java
   *    Copyright (C) 1999 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.DenseInstance;
  import weka.core.DenseInstance;
  import weka.core.Instances;
  import weka.core.Option;
  import weka.core.OptionHandler;
  import weka.core.Range;
  import weka.core.RevisionUtils;
  import weka.core.SparseInstance;
  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 all nominal attributes into binary numeric attributes. An attribute with k values is transformed into k binary attributes if the class is nominal (using the one-attribute-per-value approach). Binary attributes are left binary, if option '-A' is not given.If the class is numeric, you might want to use the supervised version of this filter.
   * <p/>
   <!-- globalinfo-end -->
   * 
   <!-- options-start -->
   * Valid options are: <p/>
   * 
   * <pre> -N
   *  Sets if binary attributes are to be coded as nominal ones.</pre>
   * 
   * <pre> -A
   *  For each nominal value a new attribute is created, 
   *  not only if there are more than 2 values.</pre>
   * 
   * <pre> -R &lt;col1,col2-col4,...&gt;
   *  Specifies list of columns to act on. First and last are 
   *  valid indexes.
   *  (default: first-last)</pre>
   * 
   * <pre> -V
   *  Invert matching sense of column indexes.</pre>
   * 
   <!-- options-end -->
   *
   * @author Eibe Frank (eibe@cs.waikato.ac.nz) 
   * @version $Revision: 5987 $ 
   */
  public class NominalToBinary 
    extends Filter 
    implements UnsupervisedFilter, OptionHandler {
    
    /** for serialization */
    static final long serialVersionUID = -1130642825710549138L;
  
    /** Stores which columns to act on */
    protected Range m_Columns = new Range();
  
    /** Are the new attributes going to be nominal or numeric ones? */
    private boolean m_Numeric = true;
  
    /** Are all values transformed into new attributes? */
    private boolean m_TransformAll = false;
  
    /** Constructor - initialises the filter */
    public NominalToBinary() {
  
      setAttributeIndices("first-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 all nominal attributes into binary numeric attributes. An "
        + "attribute with k values is transformed into k binary attributes if "
        + "the class is nominal (using the one-attribute-per-value approach). "
        + "Binary attributes are left binary, if option '-A' is not given."
        + "If the class is numeric, you might want to use the supervised version of "
        + "this filter.";
    }
  
    /** 
     * 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.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 Exception if the input format can't be set 
     * successfully
     */
    public boolean setInputFormat(Instances instanceInfo) 
         throws Exception {
  
      super.setInputFormat(instanceInfo);
  
      m_Columns.setUpper(instanceInfo.numAttributes() - 1);
  
      setOutputFormat();
      return true;
    }
  
    /**
     * Input an instance for filtering. Filter requires all
     * training instances be read before producing output.
     *
     * @param instance the input instance
     * @return true if the filtered instance may now be
     * collected with output().
     * @throws IllegalStateException if no input format has been set
     */
    public boolean input(Instance instance) {
  
      if (getInputFormat() == null) {
        throw new IllegalStateException("No input instance format defined");
      }
      if (m_NewBatch) {
        resetQueue();
        m_NewBatch = false;
      }
  
      convertInstance(instance);
      return true;
    }
  
    /**
     * Returns an enumeration describing the available options.
     *
     * @return an enumeration of all the available options.
     */
    public Enumeration listOptions() {
  
      Vector newVector = new Vector(3);
  
      newVector.addElement(new Option(
  	"\tSets if binary attributes are to be coded as nominal ones.",
  	"N", 0, "-N"));
  
      newVector.addElement(new Option(
  	"\tFor each nominal value a new attribute is created, \n"
  	+ "\tnot only if there are more than 2 values.",
  	"A", 0, "-A"));
  
      newVector.addElement(new Option(
  	"\tSpecifies list of columns to act on. First and last are \n"
  	+ "\tvalid indexes.\n"
  	+ "\t(default: first-last)",
  	"R", 1, "-R <col1,col2-col4,...>"));
  
      newVector.addElement(new Option(
  	"\tInvert matching sense of column indexes.",
  	"V", 0, "-V"));
  
      return newVector.elements();
    }
  
  
    /**
     * Parses a given list of options. <p/>
     * 
     <!-- options-start -->
     * Valid options are: <p/>
     * 
     * <pre> -N
     *  Sets if binary attributes are to be coded as nominal ones.</pre>
     * 
     * <pre> -A
     *  For each nominal value a new attribute is created, 
     *  not only if there are more than 2 values.</pre>
     * 
     * <pre> -R &lt;col1,col2-col4,...&gt;
     *  Specifies list of columns to act on. First and last are 
     *  valid indexes.
     *  (default: first-last)</pre>
     * 
     * <pre> -V
     *  Invert matching sense of column indexes.</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 {
  
      setBinaryAttributesNominal(Utils.getFlag('N', options));
  
      setTransformAllValues(Utils.getFlag('A', options));
  
      String convertList = Utils.getOption('R', options);
      if (convertList.length() != 0) {
        setAttributeIndices(convertList);
      } else {
        setAttributeIndices("first-last");
      }
      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 [4];
      int current = 0;
  
      if (getBinaryAttributesNominal()) {
        options[current++] = "-N";
      }
  
      if (getTransformAllValues()) {
        options[current++] = "-A";
      }
  
      if (!getAttributeIndices().equals("")) {
        options[current++] = "-R"; options[current++] = getAttributeIndices();
      }
      if (getInvertSelection()) {
        options[current++] = "-V";
      }
  
      while (current < options.length) {
        options[current++] = "";
      }
      return options;
    }
  
    /**
     * Returns the tip text for this property
     *
     * @return tip text for this property suitable for
     * displaying in the explorer/experimenter gui
     */
    public String binaryAttributesNominalTipText() {
      return "Whether resulting binary attributes will be nominal.";
    }
  
    /**
     * Gets if binary attributes are to be treated as nominal ones.
     *
     * @return true if binary attributes are to be treated as nominal ones
     */
    public boolean getBinaryAttributesNominal() {
  
      return !m_Numeric;
    }
  
    /**
     * Sets if binary attributes are to be treates as nominal ones.
     *
     * @param bool true if binary attributes are to be treated as nominal ones
     */
    public void setBinaryAttributesNominal(boolean bool) {
  
      m_Numeric = !bool;
    }
  
    /**
     * Returns the tip text for this property
     *
     * @return tip text for this property suitable for
     * displaying in the explorer/experimenter gui
     */
    public String transformAllValuesTipText() {
      return "Whether all nominal values are turned into new attributes, not only if there are more than 2.";
    }
  
    /**
     * Gets if all nominal values are turned into new attributes, not only if
     * there are more than 2.
     *
     * @return true all nominal values are transformed into new attributes
     */
    public boolean getTransformAllValues() {
  
      return m_TransformAll;
    }
  
    /**
     * Sets whether all nominal values are transformed into new attributes, not
     * just if there are more than 2.
     *
     * @param bool true if all nominal value are transformed into new attributes
     */
    public void setTransformAllValues(boolean bool) {
  
      m_TransformAll = bool;
    }
  
    /**
     * 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 "Set attribute selection mode. If false, only selected"
        + " (numeric) attributes in the range will be discretized; if"
        + " true, only non-selected attributes will be discretized.";
    }
  
    /**
     * Gets whether the supplied columns are to be removed or kept
     *
     * @return true if the supplied columns will be kept
     */
    public boolean getInvertSelection() {
  
      return m_Columns.getInvert();
    }
  
    /**
     * Sets 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_Columns.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\".";
    }
  
    /**
     * Gets the current range selection
     *
     * @return a string containing a comma separated list of ranges
     */
    public String getAttributeIndices() {
  
      return m_Columns.getRanges();
    }
  
    /**
     * Sets which attributes are to be acted on.
     *
     * @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
     * @throws IllegalArgumentException if an invalid range list is supplied 
     */
    public void setAttributeIndices(String rangeList) {
  
      m_Columns.setRanges(rangeList);
    }
  
    /**
     * Set the output format if the class is nominal.
     */
    private void setOutputFormat() {
  
      FastVector newAtts;
      int newClassIndex;
      StringBuffer attributeName;
      Instances outputFormat;
      FastVector vals;
  
      // Compute new attributes
  
      newClassIndex = getInputFormat().classIndex();
      newAtts = new FastVector();
      for (int j = 0; j < getInputFormat().numAttributes(); j++) {
        Attribute att = getInputFormat().attribute(j);
        if (!att.isNominal() || (j == getInputFormat().classIndex()) ||
  	  !m_Columns.isInRange(j)) {
  	newAtts.addElement(att.copy());
        } else {
  	if ( (att.numValues() <= 2) && (!m_TransformAll) ) {
  	  if (m_Numeric) {
  	    newAtts.addElement(new Attribute(att.name()));
  	  } else {
  	    newAtts.addElement(att.copy());
  	  }
  	} else {
  
  	  if (newClassIndex >= 0 && j < getInputFormat().classIndex()) {
  	    newClassIndex += att.numValues() - 1;
  	  }
  
  	  // Compute values for new attributes
  	  for (int k = 0; k < att.numValues(); k++) {
  	    attributeName = 
  	      new StringBuffer(att.name() + "=");
  	    attributeName.append(att.value(k));
  	    if (m_Numeric) {
  	      newAtts.
  		addElement(new Attribute(attributeName.toString()));
  	    } else {
  	      vals = new FastVector(2);
  	      vals.addElement("f"); vals.addElement("t");
  	      newAtts.
  		addElement(new Attribute(attributeName.toString(), vals));
  	    }
  	  }
  	}
        }
      }
      outputFormat = new Instances(getInputFormat().relationName(),
  				 newAtts, 0);
      outputFormat.setClassIndex(newClassIndex);
      setOutputFormat(outputFormat);
    }
  
    /**
     * Convert a single instance over if the class is nominal. The converted 
     * instance is added to the end of the output queue.
     *
     * @param instance the instance to convert
     */
    private void convertInstance(Instance instance) {
  
      double [] vals = new double [outputFormatPeek().numAttributes()];
      int attSoFar = 0;
  
      for(int j = 0; j < getInputFormat().numAttributes(); j++) {
        Attribute att = getInputFormat().attribute(j);
        if (!att.isNominal() || (j == getInputFormat().classIndex()) ||
  	  !m_Columns.isInRange(j)) {
  	vals[attSoFar] = instance.value(j);
  	attSoFar++;
        } else {
  	if ( (att.numValues() <= 2) && (!m_TransformAll) ) {
  	  vals[attSoFar] = instance.value(j);
  	  attSoFar++;
  	} else {
  	  if (instance.isMissing(j)) {
  	    for (int k = 0; k < att.numValues(); k++) {
                vals[attSoFar + k] = instance.value(j);
  	    }
  	  } else {
  	    for (int k = 0; k < att.numValues(); k++) {
  	      if (k == (int)instance.value(j)) {
                  vals[attSoFar + k] = 1;
  	      } else {
                  vals[attSoFar + k] = 0;
  	      }
  	    }
  	  }
  	  attSoFar += att.numValues();
  	}
        }
      }
      Instance inst = null;
      if (instance instanceof SparseInstance) {
        inst = new SparseInstance(instance.weight(), vals);
      } else {
        inst = new DenseInstance(instance.weight(), vals);
      }
      inst.setDataset(getOutputFormat());
      copyValues(inst, false, instance.dataset(), getOutputFormat());
      inst.setDataset(getOutputFormat());
      push(inst);
    }
    
    /**
     * Returns the revision string.
     * 
     * @return		the revision
     */
    public String getRevision() {
      return RevisionUtils.extract("$Revision: 5987 $");
    }
  
    /**
     * Main method for testing this class.
     *
     * @param argv should contain arguments to the filter: 
     * use -h for help
     */
    public static void main(String [] argv) {
      runFilter(new NominalToBinary(), argv);
    }
  }
  