code: def generate_thresholdcurve_data(evaluation, class_index):
      
      jtc = JavaObject.new_instance("weka.classifiers.evaluation.ThresholdCurve")
      pred = javabridge.call(evaluation.jobject, "predictions", "()Ljava/util/ArrayList;")
      result = Instances(
          javabridge.call(jtc, "getCurve", "(Ljava/util/ArrayList;I)Lweka/core/Instances;", pred, class_index))
      return result
docs: Generates the threshold curve data from the evaluation object's predictions.
  
      :param evaluation: the evaluation to obtain the predictions from
      :type evaluation: Evaluation
      :param class_index: the 0-based index of the class-label to create the plot for
      :type class_index: int
      :return: the generated threshold curve data
      :rtype: Instances