FastVector attributes = new FastVector(attributeNumber);attributes.addElement(attrA);attributes.addElement(attrB);attributes.addElement(attrC);attributes.addElement(attrClass);
Instances trainingData = new Instances("trainingdata",attributes,10);// this assigns indices to attributes, without these indices I cannot create instances.
trainingData.setClassIndex(attrClass.index());
Instance inst = new Instance(attributeNumber);
inst.setValue(attrA,0);inst.setValue(attrB, 1);inst.setValue(attrC, 1);inst.setValue(attrClass, 0);
Assert.assertEquals(4,trainingData.numAttributes());
Assert.assertEquals(0,trainingData.numInstances());
trainingData.add(inst);
Assert.assertEquals(4,trainingData.numAttributes());
Assert.assertEquals(1,trainingData.numInstances());
}