import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.util.Random;

import weka.classifiers.Evaluation;
import weka.classifiers.bayes.NaiveBayes;
import weka.core.Instances;

public class WekaApi {

	public static void main(String[] args) throws Exception {
		// TODO Auto-generated method stub
		BufferedReader breader = null;
		
		breader = new BufferedReader(new FileReader("c:/pogoda.arff"));
		
		Instances train = new Instances (breader);
		train.setClassIndex(train.numAttributes()-1);
		
		breader.close();
		
		NaiveBayes nB = new NaiveBayes();
		nB.buildClassifier(train);
		Evaluation eval = new Evaluation(train);
		eval.crossValidateModel(nB, train, 10, new Random(1));
		System.out.println(eval.toSummaryString("\nResults\n======\n",true));
		System.out.println(eval.fMeasure(1) + "" + eval.precision(1)+ "" + eval.recall(1));
		
		

	}

}