title: J48 Classifier - python-weka-wrapper -- selecting Class attribute
body: <p>I am trying to apply the j48 classifier on a dataset, but I am not understanding how to actually select the right attribute as the class. 
  I found a method called class_is_last() which sets the last attribute as the class, but what if I want to select my attribute called say 'name' as the class? </p>
  
  <pre><code>jvm.start()
  loader = Loader(classname="weka.core.converters.ArffLoader")
  dataweka = loader.load_file("enumeratedremovedtest-arff.arff")
  dataarff = arff.load(open('enumeratedremovedtest-arff.arff', 'rb'))
  
  from weka.classifiers import Classifier
  dataweka.class_is_last()
  cls = Classifier(classname="weka.classifiers.trees.J48", options=["-C","0.25", "-B", "-M", "2"])
  print dataweka.class_attribute
  cls.build_classifier(dataweka)
  
  print(cls)
  </code></pre>
  
  <p>jvm.stop()</p>
  
  <p>All required modules have been imported, and this works as expected and uses the last attribute in the list as the class. </p>