ValueReplenishmentModel.java

/**
 * Copyright (C) 2001-2017 by RapidMiner and the contributors
 * 
 * Complete list of developers available at our web site:
 * 
 * http://rapidminer.com
 * 
 * This program is free software: you can redistribute it and/or modify it under the terms of the
 * GNU Affero 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
 * Affero General Public License for more details.
 * 
 * You should have received a copy of the GNU Affero General Public License along with this program.
 * If not, see http://www.gnu.org/licenses/.
*/
package com.rapidminer.operator.preprocessing.filter;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import com.rapidminer.example.Attribute;
import com.rapidminer.example.Attributes;
import com.rapidminer.example.Example;
import com.rapidminer.example.ExampleSet;
import com.rapidminer.example.table.ViewAttribute;
import com.rapidminer.operator.OperatorException;
import com.rapidminer.operator.OperatorProgress;
import com.rapidminer.operator.preprocessing.PreprocessingModel;
import com.rapidminer.tools.Ontology;


/**
 * This class provides the preprocessing model for all value replacing operators.
 *
 * @author Sebastian Land
 *
 */
public class ValueReplenishmentModel extends PreprocessingModel {

	private static final long serialVersionUID = -4886756106998999255L;

	private HashMap<String, Double> numericalAndDateReplacementMap;
	private HashMap<String, String> nominalReplacementMap;

	private double replaceWhat;

	private HashMap<Attribute, Double> attributeReplacementMap = new HashMap<Attribute, Double>();

	public ValueReplenishmentModel(ExampleSet exampleSet, double replacedValue,
			HashMap<String, Double> numericalAndDateReplacementMap, HashMap<String, String> nominalReplacementMap) {
		super(exampleSet);
		this.replaceWhat = replacedValue;
		this.nominalReplacementMap = nominalReplacementMap;
		this.numericalAndDateReplacementMap = numericalAndDateReplacementMap;
	}

	@Override
	public ExampleSet applyOnData(ExampleSet exampleSet) throws OperatorException {
		Attributes attributes = exampleSet.getAttributes();
		boolean[] replace = new boolean[attributes.size()];
		double[] by = new double[attributes.size()];
		int i = 0;
		for (Attribute attribute : attributes) {
			if (attribute.isNominal()) {
				String replacement = nominalReplacementMap.get(attribute.getName());
				if (replacement != null) {
					replace[i] = true;
					by[i] = attribute.getMapping().mapString(replacement);
				}
			}
			if (attribute.isNumerical() || Ontology.ATTRIBUTE_VALUE_TYPE.isA(attribute.getValueType(), Ontology.DATE_TIME)) {
				Double replacement = numericalAndDateReplacementMap.get(attribute.getName());
				if (replacement != null) {
					replace[i] = true;
					by[i] = replacement;
				}
			}
			i++;
		}

		// initialize progress
		OperatorProgress progress = null;
		long progressCounter = 0;
		long totalProgress = (long) attributes.size() * exampleSet.size();
		if (getShowProgress() && getOperator() != null && getOperator().getProgress() != null) {
			progress = getOperator().getProgress();
			progress.setTotal(1000);
		}

		i = 0;
		for (Attribute attribute : attributes) {
			for (Example example : exampleSet) {
				if (replace[i]) {
					double value = example.getValue(attribute);
					if (value == replaceWhat || Double.isNaN(replaceWhat) && Double.isNaN(value)) {
						// special NaN treatment
						example.setValue(attribute, by[i]);
					}
				}
				if (progress != null && ++progressCounter % 100_000 == 0) {
					progress.setCompleted((int) (1000.0d * progressCounter / totalProgress));
				}
			}
			i++;
		}
		return exampleSet;
	}

	@Override
	public Attributes getTargetAttributes(ExampleSet viewParent) {
		List<Attribute> targetAttributes = new ArrayList<>();
		Attributes attributes = viewParent.getAttributes();
		Iterator<Attribute> iterator = attributes.allAttributes();
		while (iterator.hasNext()) {
			Attribute attribute = iterator.next();
			if (attribute.isNominal()) {
				String replacement = nominalReplacementMap.get(attribute.getName());
				if (replacement != null) {
					// create view attribute and store
					Attribute viewAttribute = new ViewAttribute(this, attribute, attribute.getName(),
							attribute.getValueType(), attribute.getMapping());
					attributeReplacementMap.put(viewAttribute, (double) attribute.getMapping().mapString(replacement));
					targetAttributes.add(viewAttribute);
					// delete original attribute
					iterator.remove();
				}
			}
			if (attribute.isNumerical() || Ontology.ATTRIBUTE_VALUE_TYPE.isA(attribute.getValueType(), Ontology.DATE_TIME)) {
				Double replacement = numericalAndDateReplacementMap.get(attribute.getName());
				if (replacement != null) {
					// create view attribute and store
					Attribute viewAttribute = new ViewAttribute(this, attribute, attribute.getName(),
							attribute.getValueType(), null);
					attributeReplacementMap.put(viewAttribute, replacement);
					targetAttributes.add(viewAttribute);
					// delete original attribute
					iterator.remove();
				}
			}
		}

		for (Attribute attribute : targetAttributes) {
			attributes.addRegular(attribute);
		}

		return attributes;
	}

	@Override
	public double getValue(Attribute targetAttribute, double value) {
		if (replaceWhat == value || Double.isNaN(replaceWhat) && Double.isNaN(value)) {
			return attributeReplacementMap.get(targetAttribute);
		} else {
			return value;
		}
	}

	public Map<String, Double> getNumericalAndDateReplacementMap() {
		return numericalAndDateReplacementMap;
	}

	public Map<String, String> getNominalReplacementMap() {
		return nominalReplacementMap;
	}

	public double getReplaceWhat() {
		return replaceWhat;
	}

	public Map<Attribute, Double> getAttributeReplacementMap() {
		return attributeReplacementMap;
	}

	@Override
	protected boolean writesIntoExistingData() {
		return true;
	}

	@Override
	protected boolean needsRemapping() {
		return false;
	}

}