AdaptiveRandomForest-master/src/main/java/moa/classifiers/core/conditionaltests/NominalAttributeMultiwayTest.java
/*
 *    NominalAttributeMultiwayTest.java
 *    Copyright (C) 2007 University of Waikato, Hamilton, New Zealand
 *    @author Richard Kirkby (rkirkby@cs.waikato.ac.nz)
 *
 *    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/>.
 *    
 */
package moa.classifiers.core.conditionaltests;

import com.yahoo.labs.samoa.instances.InstancesHeader;
import com.yahoo.labs.samoa.instances.Instance;

/**
 * Nominal multi way conditional test for instances to use to split nodes in Hoeffding trees.
 *
 * @author Richard Kirkby (rkirkby@cs.waikato.ac.nz)
 * @version $Revision: 7 $
 */
public class NominalAttributeMultiwayTest extends InstanceConditionalTest {

    private static final long serialVersionUID = 1L;

    protected int attIndex;

    public NominalAttributeMultiwayTest(int attIndex) {
        this.attIndex = attIndex;
    }

    @Override
    public int branchForInstance(Instance inst) {
        int instAttIndex = this.attIndex  ; //< inst.classIndex() ? this.attIndex
                //: this.attIndex + 1;
        return inst.isMissing(instAttIndex) ? -1 : (int) inst.value(instAttIndex);
    }

    @Override
    public String describeConditionForBranch(int branch, InstancesHeader context) {
        return InstancesHeader.getAttributeNameString(context, this.attIndex)
                + " = "
                + InstancesHeader.getNominalValueString(context, this.attIndex,
                branch);
    }

    @Override
    public int maxBranches() {
        return -1;
    }

    @Override
    public void getDescription(StringBuilder sb, int indent) {
        // TODO Auto-generated method stub
    }

    @Override
    public int[] getAttsTestDependsOn() {
        return new int[]{this.attIndex};
    }
}
