决策树之Python实现 from math import log import operator #创建数据集 def createDataSet(): dataSet=[[1,1,’yes’],[1,1,’yes’],[1,0,’no’],[0,1,’no’],[0,1,’no’]] labels=[‘no surfacing’,’flippers’] return dataSet,labels #计算给定数据集的香农熵 def calcShannonEnt(dataSet): numEntries=len(dataset) la
