java - Weka 决策树 Java 到列表

Question

我想制作一个决策树并将其分解为列表(name、sign、val)。我用这段代码做了树:

        //Get File
        BufferedReader reader = new BufferedReader(new FileReader(PATH + "TempArffFile.arff"));

        //Get the data
        Instances data = new Instances(reader);
        reader.close();

        //Setting class attribute 
        data.setClassIndex(data.numAttributes() - 1);

        //Make tree
        J48 tree = new J48();
        String[] options = new String[1];
        options[0] = "-U"; 
        tree.setOptions(options);
        tree.buildClassifier(data);

        //Print tree
        System.out.println(tree);

现在我需要将它分解为数组，我该怎么做？

例子:我得到这棵树:

title <= 1: bad (4.0)
title > 1
|   positionMatch <= 1
|   |   countryCode <= 1: good (3.0/1.0)
|   |   countryCode > 1: bad (8.0/3.0)
|   positionMatch > 1: good (4.0/1.0)

所以我想从那棵树中得到 4 个列表:

• title(<= 1) -> bad
• title(> 1) -> position(<= 1) -> countryCode(<= 1) -> good
• title(> 1) -> position(<= 1) -> countryCode(> 1) -> bad
• title(> 1) -> position(> 1) -> good

我该怎么做？

Answer 1

不是很好，但也许比什么都没有好...也许它会给你一个想法。

    public static void split(String tree){

    String[] lines = tree.split("\n");
    List<List<String>> lists = new ArrayList<List<String>>(); 
    for(String line : lines){
        List<String> temp = new ArrayList<String>();
        while(line.indexOf("|") != -1){
            temp.add("|");
            line = line.replaceFirst("\\|", "");
        }
        temp.add(line.trim());
        lists.add(temp);
    }

    for(int i = 0; i < 3; i++){
        lists.remove(0);
    }
    for(int i = 0; i < 4; i++){
        lists.remove(lists.size()-1);
    }
    List<String> substitutes = new ArrayList<String>();

    for(List<String> list : lists){
        for(int i = 0; i < list.size(); i++){
            if(!list.get(i).contains(":") && !list.get(i).equals("|") && !substitutes.contains(list.get(i))){
                substitutes.add(list.get(i));
            }
        }
    }
    for(List<String> list : lists){
        for(int i = 0; i < list.size(); i++){
            if(list.get(i).equals("|")){
                list.set(i, substitutes.get(i));
            }
        }
    }
    StringBuilder sb = new StringBuilder();
    for(List<String> list : lists){
        String line = "";
        for(String s : list){
            line = line+" "+s;
        }
        if(line.endsWith(")")){
            sb.append(line+"\n");
        }
    }
    System.out.println(sb.toString());
}

输入

J48 未修剪树

花瓣宽度 <= 0.6:鸢尾花 (50.0)

花瓣宽度 > 0.6

|花瓣宽度 <= 1.7

| | petallength <= 4.9: Iris-versicolor (48.0/1.0)

| |花瓣长度 > 4.9

| | |花瓣宽度 <= 1.5:Iris-virginica (3.0)

| | | petalwidth > 1.5: Iris-versicolor (3.0/1.0)

| petalwidth > 1.7: Iris-virginica (46.0/1.0)

叶子数:5

树的大小:9

输出:

花瓣宽度 <= 0.6:鸢尾花 (50.0)

petalwidth > 0.6 petalwidth <= 1.7 petallength <= 4.9: Iris-versicolor (48.0/1.0)

petalwidth > 0.6 petalwidth <= 1.7 petallength > 4.9 petalwidth <= 1.5: Iris-virginica (3.0)

petalwidth > 0.6 petalwidth <= 1.7 petallength > 4.9 petalwidth > 1.5: Iris-versicolor (3.0/1.0)

花瓣宽度 > 0.6 花瓣宽度 > 1.7:Iris-virginica (46.0/1.0)