package attributeSelection;

import java.io.File;

import weka.attributeSelection.AttributeSelection;
import weka.attributeSelection.CfsSubsetEval;
import weka.attributeSelection.GreedyStepwise;
import weka.core.Instances;
import weka.core.Utils;
import weka.core.converters.ArffLoader;

//使用底层API
public class UseLowLevel {

	public static void main(String[] args) throws Exception {
		// 加载数据
		ArffLoader loader = new ArffLoader();
		loader.setFile(new File("data/weather.numeric.arff"));
		Instances data = loader.getDataSet();
		if (data.classIndex() == -1) {// 设置最后一个属性作为类别属性
			data.setClassIndex(data.numAttributes() - 1);
		}

		// 训练聚类器
		AttributeSelection attsel=new AttributeSelection();
		CfsSubsetEval eval=new CfsSubsetEval();
		GreedyStepwise search=new GreedyStepwise();
		search.setSearchBackwards(true);
		attsel.setEvaluator(eval);
		attsel.setSearch(search);
		attsel.SelectAttributes(data);
		
		int[] indices=attsel.selectedAttributes();
		System.out.println("选择属性索引（从0开始）：\n"+Utils.arrayToString(indices));
		

	}

}