liac.igmn.loader.DataLoader.java Source code

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Here is the source code for liac.igmn.loader.DataLoader.java

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/**
* =============================================================================
* Federal University of Rio Grande do Sul (UFRGS)
* Connectionist Artificial Intelligence Laboratory (LIAC)
* Edigleison F. Carvalho - edigleison.carvalho@inf.ufrgs.br
* =============================================================================
* Copyright (c) 2012 Edigleison F. Carvalho, edigleison.carvalho at gmail dot com
* 
* Permission is hereby granted, free of charge, to any person obtaining a copy 
* of this software and associated documentation files (the "Software"), to deal 
* in the Software without restriction, including without limitation the rights 
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 
* copies of the Software, and to permit persons to whom the Software is 
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in 
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 
* SOFTWARE.
* =============================================================================
*/

package liac.igmn.loader;

import java.io.File;
import java.io.IOException;

import weka.core.Instances;
import weka.core.converters.ArffLoader;
import weka.filters.Filter;
import weka.filters.unsupervised.attribute.NominalToBinary;

public class DataLoader {
    private DataLoader() {
    }

    /**
     * Carrega dataset a partir de arquivo ARFF e binariza os atributos nominais.
     * Assume que a classe seja o ultimo atributo.
     * 
     * @param filename path do arquivo
     * @return dataset
     * @throws DataLoaderException lancado quando o arquivo nao e encontrado
     * ou quando ocorre algum erro de IO
     */
    public static Dataset loadARFF(String filename) throws DataLoaderException {
        Dataset dataset = new Dataset();
        try {
            ArffLoader loader = new ArffLoader();

            loader.setSource(new File(filename));
            Instances data = loader.getDataSet();
            Instances m_Intances = new Instances(data);

            data.setClassIndex(data.numAttributes() - 1);

            String[] classes = new String[data.numClasses()];
            for (int i = 0; i < data.numClasses(); i++)
                classes[i] = data.classAttribute().value(i);
            dataset.setClassesNames(classes);

            NominalToBinary filter = new NominalToBinary();
            filter.setInputFormat(m_Intances);
            filter.setOptions(new String[] { "-A" });
            m_Intances = Filter.useFilter(m_Intances, filter);

            int inputSize = m_Intances.numAttributes() - data.numClasses();

            dataset.setInputSize(inputSize);
            dataset.setNumClasses(data.numClasses());

            dataset.setWekaDataset(m_Intances);
        } catch (IOException e) {
            throw new DataLoaderException("Arquivo no encontrado", e.getCause());
        } catch (Exception e) {
            throw new DataLoaderException("Falha na converso do arquivo", e.getCause());
        }

        return dataset;
    }
}