/**
  * Trains this classifier incrementally using the given instance.
  *
  * @param inst the instance to be used for training
  */
 @Override
 public void trainOnInstance(Instance inst) {
   if (this.isInit == false) {
     this.isInit = true;
     InstancesHeader instances = new InstancesHeader(dataset);
     this.learner.setModelContext(instances);
     this.learner.prepareForUse();
   }
   if (inst.weight() > 0) {
     inst.setDataset(dataset);
     learner.trainOnInstance(inst);
   }
 }