Remove delTransform = new Remove();
delTransform.setInvertSelection(true);
// copy the instances
Instances trainCopy = new Instances(m_trainInstances);
featArray[0] = attribute;
featArray[1] = trainCopy.classIndex();
delTransform.setAttributeIndicesArray(featArray);
delTransform.setInputFormat(trainCopy);
trainCopy = Filter.useFilter(trainCopy, delTransform);
o_Evaluation = new Evaluation(trainCopy);
String [] oneROpts = { "-B", ""+getMinimumBucketSize()};