com.rapidminer.operator.preprocessing.discretization.BinDiscretization.java Source code

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Here is the source code for com.rapidminer.operator.preprocessing.discretization.BinDiscretization.java

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/**
 * 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.discretization;

import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Set;
import java.util.TreeSet;

import org.apache.commons.lang.ArrayUtils;

import com.rapidminer.example.Attribute;
import com.rapidminer.example.ExampleSet;
import com.rapidminer.example.Statistics;
import com.rapidminer.operator.OperatorDescription;
import com.rapidminer.operator.OperatorException;
import com.rapidminer.operator.OperatorVersion;
import com.rapidminer.operator.UserError;
import com.rapidminer.operator.annotation.ResourceConsumptionEstimator;
import com.rapidminer.operator.ports.metadata.AttributeMetaData;
import com.rapidminer.operator.ports.metadata.ExampleSetMetaData;
import com.rapidminer.operator.ports.metadata.SetRelation;
import com.rapidminer.operator.preprocessing.PreprocessingModel;
import com.rapidminer.parameter.ParameterType;
import com.rapidminer.parameter.ParameterTypeBoolean;
import com.rapidminer.parameter.ParameterTypeCategory;
import com.rapidminer.parameter.ParameterTypeDouble;
import com.rapidminer.parameter.ParameterTypeInt;
import com.rapidminer.parameter.UndefinedParameterError;
import com.rapidminer.parameter.conditions.BooleanParameterCondition;
import com.rapidminer.parameter.conditions.EqualTypeCondition;
import com.rapidminer.tools.Ontology;
import com.rapidminer.tools.OperatorResourceConsumptionHandler;

/**
 * This operator discretizes all numeric attributes in the dataset into nominal attributes. This
 * discretization is performed by simple binning, i.e. the specified number of equally sized bins is
 * created and the numerical values are simply sorted into those bins. Skips all special attributes
 * including the label.
 *
 * @author Sebastian Land, Ingo Mierswa
 */
public class BinDiscretization extends AbstractDiscretizationOperator {

    static {
        registerDiscretizationOperator(BinDiscretization.class);
    }
    private static final String RANGE_NAME_BASE = "range";

    /** Indicates the number of used bins. */
    public static final String PARAMETER_NUMBER_OF_BINS = "number_of_bins";

    public static final String PARAMETER_DEFINE_BOUNDARIES = "define_boundaries";

    public static final String PARAMETER_MIN_VALUE = "min_value";

    public static final String PARAMETER_MAX_VALUE = "max_value";

    /** Indicates if long range names should be used. */
    public static final String PARAMETER_RANGE_NAME_TYPE = "range_name_type";

    public static final String PARAMETER_AUTOMATIC_NUMBER_OF_DIGITS = "automatic_number_of_digits";

    public static final String PARAMETER_NUMBER_OF_DIGITS = "number_of_digits";

    /**
     * Incompatible version, old version writes into the exampleset, if original output port is not
     * connected.
     */
    private static final OperatorVersion VERSION_MAY_WRITE_INTO_DATA = new OperatorVersion(7, 1, 1);

    public BinDiscretization(OperatorDescription description) {
        super(description);
    }

    @Override
    protected Collection<AttributeMetaData> modifyAttributeMetaData(ExampleSetMetaData emd, AttributeMetaData amd)
            throws UndefinedParameterError {
        AttributeMetaData newAMD = new AttributeMetaData(amd.getName(), Ontology.NOMINAL, amd.getRole());
        Set<String> valueSet = new TreeSet<String>();
        if (getParameterAsInt(PARAMETER_RANGE_NAME_TYPE) == DiscretizationModel.RANGE_NAME_SHORT) {
            for (int i = 0; i < getParameterAsInt(PARAMETER_NUMBER_OF_BINS); i++) {
                valueSet.add(RANGE_NAME_BASE + (i + 1));
            }
            newAMD.setValueSet(valueSet, SetRelation.EQUAL);
        } else {
            newAMD.setValueSet(valueSet, SetRelation.SUPERSET);
        }
        return Collections.singletonList(newAMD);
    }

    @Override
    public PreprocessingModel createPreprocessingModel(ExampleSet exampleSet) throws OperatorException {
        DiscretizationModel model = new DiscretizationModel(exampleSet);

        exampleSet.recalculateAllAttributeStatistics();
        int numberOfBins = getParameterAsInt(PARAMETER_NUMBER_OF_BINS);
        HashMap<Attribute, double[]> ranges = new HashMap<Attribute, double[]>();

        if (getParameterAsBoolean(PARAMETER_DEFINE_BOUNDARIES)) {
            double min = getParameterAsDouble(PARAMETER_MIN_VALUE);
            double max = getParameterAsDouble(PARAMETER_MAX_VALUE);
            if (min > max) {
                throw new UserError(this, 116, PARAMETER_MIN_VALUE + " and " + PARAMETER_MAX_VALUE,
                        "minimum must be less than maximum");
            }
            for (Attribute attribute : exampleSet.getAttributes()) {
                if (attribute.isNumerical()) { // skip nominal and date attributes
                    double[] binRange = new double[numberOfBins + 2];
                    binRange[0] = min;
                    for (int b = 1; b < numberOfBins; b++) {
                        binRange[b] = min + (((double) b / (double) numberOfBins) * (max - min));
                    }
                    binRange[numberOfBins] = max;
                    binRange[numberOfBins + 1] = Double.POSITIVE_INFINITY;
                    ranges.put(attribute, binRange);
                }
            }
        } else {
            for (Attribute attribute : exampleSet.getAttributes()) {
                if (attribute.isNumerical()) { // skip nominal and date attributes
                    double[] binRange = new double[numberOfBins];
                    double min = exampleSet.getStatistics(attribute, Statistics.MINIMUM);
                    double max = exampleSet.getStatistics(attribute, Statistics.MAXIMUM);
                    for (int b = 0; b < numberOfBins - 1; b++) {
                        binRange[b] = min + (((double) (b + 1) / (double) numberOfBins) * (max - min));
                    }
                    binRange[numberOfBins - 1] = Double.POSITIVE_INFINITY;
                    ranges.put(attribute, binRange);
                }
            }
        }

        // determine number of digits
        int numberOfDigits = -1;
        if (getParameterAsBoolean(PARAMETER_AUTOMATIC_NUMBER_OF_DIGITS) == false) {
            numberOfDigits = getParameterAsInt(PARAMETER_NUMBER_OF_DIGITS);
        }

        model.setRanges(ranges, RANGE_NAME_BASE, getParameterAsInt(PARAMETER_RANGE_NAME_TYPE), numberOfDigits);
        return (model);
    }

    @Override
    public Class<? extends PreprocessingModel> getPreprocessingModelClass() {
        return DiscretizationModel.class;
    }

    @Override
    public List<ParameterType> getParameterTypes() {
        List<ParameterType> types = super.getParameterTypes();

        ParameterType type = new ParameterTypeInt(PARAMETER_NUMBER_OF_BINS,
                "Defines the number of bins which should be used for each attribute.", 2, Integer.MAX_VALUE, 2);
        type.setExpert(false);
        types.add(type);

        type = new ParameterTypeBoolean(PARAMETER_DEFINE_BOUNDARIES,
                "Define the boundraries for the bin calculation.", false);
        types.add(type);
        type = new ParameterTypeDouble(PARAMETER_MIN_VALUE, "The minimum value for the binning range.",
                Double.NEGATIVE_INFINITY, Double.POSITIVE_INFINITY, true);
        type.registerDependencyCondition(
                new BooleanParameterCondition(this, PARAMETER_DEFINE_BOUNDARIES, true, true));
        types.add(type);
        type = new ParameterTypeDouble(PARAMETER_MAX_VALUE, "The maximum value for the binning range.",
                Double.NEGATIVE_INFINITY, Double.POSITIVE_INFINITY, true);
        type.registerDependencyCondition(
                new BooleanParameterCondition(this, PARAMETER_DEFINE_BOUNDARIES, true, true));
        types.add(type);

        types.add(new ParameterTypeCategory(PARAMETER_RANGE_NAME_TYPE,
                "Indicates if long range names including the limits should be used.",
                DiscretizationModel.RANGE_NAME_TYPES, DiscretizationModel.RANGE_NAME_LONG));

        type = new ParameterTypeBoolean(PARAMETER_AUTOMATIC_NUMBER_OF_DIGITS,
                "Indicates if the number of digits should be automatically determined for the range names.", true);
        type.registerDependencyCondition(new EqualTypeCondition(this, PARAMETER_RANGE_NAME_TYPE,
                DiscretizationModel.RANGE_NAME_TYPES, false, DiscretizationModel.RANGE_NAME_INTERVAL));
        types.add(type);

        type = new ParameterTypeInt(PARAMETER_NUMBER_OF_DIGITS,
                "The minimum number of digits used for the interval names.", 1, Integer.MAX_VALUE, 3);
        type.registerDependencyCondition(
                new BooleanParameterCondition(this, PARAMETER_AUTOMATIC_NUMBER_OF_DIGITS, false, false));
        types.add(type);

        return types;
    }

    @Override
    public boolean writesIntoExistingData() {
        if (getCompatibilityLevel().isAbove(VERSION_MAY_WRITE_INTO_DATA)) {
            return false;
        } else {
            // old version: true only if original output port is connected
            return isOriginalOutputConnected() && super.writesIntoExistingData();
        }
    }

    @Override
    public ResourceConsumptionEstimator getResourceConsumptionEstimator() {
        return OperatorResourceConsumptionHandler.getResourceConsumptionEstimator(getInputPort(),
                BinDiscretization.class, attributeSelector);
    }

    @Override
    public OperatorVersion[] getIncompatibleVersionChanges() {
        return (OperatorVersion[]) ArrayUtils.addAll(super.getIncompatibleVersionChanges(),
                new OperatorVersion[] { VERSION_MAY_WRITE_INTO_DATA });
    }
}