Examples with MekaClassAttributes meka.filters.unsupervised.attribute.MekaClassAttributes used on opensource projects

Example 1 with MekaClassAttributes

use of meka.filters.unsupervised.attribute.MekaClassAttributes in project dkpro-tc by dkpro.

the class WekaUtils method applyAttributeSelectionFilter.

/**
 * Applies a filter to reduce the dimension of attributes and reorders them to be used within
 * Meka
 *
 * @param trainData
 *            the train data
 * @param removeFilter
 *            remove filter
 * @return weka instances
 * @throws Exception
 *             in case of error
 */
public static Instances applyAttributeSelectionFilter(Instances trainData, Remove removeFilter) throws Exception {
    // less attributes than should be kept => ignore filter
    if (removeFilter == null) {
        return trainData;
    }
    Instances filtered = Filter.useFilter(trainData, removeFilter);
    filtered.setClassIndex(trainData.classIndex());
    // swap attributes to fit MEKA
    MekaClassAttributes attFilter = new MekaClassAttributes();
    attFilter.setAttributeIndices(filtered.numAttributes() - trainData.classIndex() + 1 + "-last");
    attFilter.setInputFormat(filtered);
    filtered = Filter.useFilter(filtered, attFilter);
    int newClassindex = filtered.classIndex();
    filtered.setRelationName(filtered.relationName().replaceAll("\\-C\\s[\\d]+", "-C " + newClassindex));
    return filtered;
}