统计学习方法第五章：ID3/C4.5算法分类决策树及平方误差二叉回归树代码实现

    import numpy as np
    import math
    class Node:
    def __init__(self,feature_index=None,value=None,label=None):
        self.feature_index=feature_index
        self.value=value
        self.child=[]
        self.label=label
    
    
    class C4_5:
    def __init__(self,X,Y,c=0.1,way='ID3'):
        self.c = c
        self.root=Node()
        self.X = X
        self.Y = Y
        self.feature_num = len(X[0])
        self.label_num = len(Y)
        self.feature_set = list(range(self.feature_num))
        self.getac()
        self.way = way
    
    def getac