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.
   */
  
  /*
   *    SparseToNonSparse.java
   *    Copyright (C) 2002 University of Waikato, Hamilton, New Zealand
   *
   */
  
  
  package weka.filters.unsupervised.instance;
  
  import weka.core.Capabilities;
  import weka.core.Instance;
  import weka.core.DenseInstance;
  import weka.core.Instances;
  import weka.core.RevisionUtils;
  import weka.core.SparseInstance;
  import weka.core.Capabilities.Capability;
  import weka.filters.Filter;
  import weka.filters.StreamableFilter;
  import weka.filters.UnsupervisedFilter;
  
  /** 
   <!-- globalinfo-start -->
   * An instance filter that converts all incoming sparse instances into non-sparse format.
   * <p/>
   <!-- globalinfo-end -->
   * 
   * @author Len Trigg (len@reeltwo.com)
   * @version $Revision: 5987 $ 
   */
  public class SparseToNonSparse 
    extends Filter 
    implements UnsupervisedFilter, StreamableFilter {
  
    /** for serialization */
    static final long serialVersionUID = 2481634184210236074L;
    
    /**
     * 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 converts all incoming sparse instances"
        + " into non-sparse format.";
    }
  
    /** 
     * 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 format cannot be processed
     */
    public boolean setInputFormat(Instances instanceInfo) throws Exception {
  
      super.setInputFormat(instanceInfo);
      setOutputFormat(instanceInfo);
      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().
     * @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;
      }
      Instance inst = null;
      if (instance instanceof SparseInstance) {
        inst = new DenseInstance(instance.weight(), instance.toDoubleArray());
        inst.setDataset(instance.dataset());
      } else {
        inst = instance;
      }
      push(inst);
      return true;
    }
    
    /**
     * 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 SparseToNonSparse(), argv);
    }
  }
  