#6 ArrayIndexOutOfBoundsException

[Anonymous]

Hi,

I using the 'emotions.arff' example arff file, with only the first 20 instances. But when I use cross-validation, I get the following error:

Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: -1
at mulan.evaluation.measure.MeanAverageInterpolatedPrecision.highestPrecisionAfterPos(MeanAverageInterpolatedPrecision.java:123)
at mulan.evaluation.measure.MeanAverageInterpolatedPrecision.getValue(MeanAverageInterpolatedPrecision.java:103)
at mulan.evaluation.MultipleEvaluation.calculateStatistics(MultipleEvaluation.java:92)
at mulan.evaluation.Evaluator.innerCrossValidate(Evaluator.java:283)
at mulan.evaluation.Evaluator.crossValidate(Evaluator.java:240)

My code:
import mulan.classifier.lazy.MLkNN;
import mulan.classifier.transformation.LabelPowerset;
import mulan.data.MultiLabelInstances;
import mulan.evaluation.Evaluator;
import mulan.evaluation.MultipleEvaluation;
import weka.classifiers.trees.J48;
import weka.core.Utils;

public class Mulan {

public static void main(String[] args) throws Exception {
    String arffFilename = Utils.getOption("arff", args); // e.g. -arff emotions.arff                                                                                                                    
    String xmlFilename = Utils.getOption("xml", args); // e.g. -xml emotions.xml

    MultiLabelInstances dataset = new MultiLabelInstances(arffFilename, xmlFilename);
    MLkNN learner2 = new MLkNN();

    Evaluator eval = new Evaluator();
    MultipleEvaluation results;

    int numFolds = 2;                                                                                                                                                                   
    results = eval.crossValidate(learner2, dataset, numFolds);
    System.out.println(results);
}

}

[laskstef]

Hello!
This was indeed a bug in a previous version of Mulan.
Please, try svn checkout svn://svn.code.sf.net/p/mulan/code/trunk mulan-code and try re-running your code.

If you come across the same problem, please contact us.

Thank you for your interest on behalf of the Mulan team.

Stefanos