KNN算法学习笔记二

def  file2matrix(filename):     fr=open(filename)#打开文件     arrayOfLines=fr.readlines()#读取每一行     numberOfLines=len(arrayOfLines)#统计行数     returnMat=zeros((numberOfLines,3))#转换成矩阵     classLabelVector=[]     index=0     for line in arrayOfLines:          line=line.strip()#去掉转义符          listFromLine=line.split('\t')#截取字符串          returnMat[index:]=listFromLine[0:3]#取前三组数据          classLabelVector.append(int(listFromLine[-1]))#将最后一列数据存入          index+=1     return returnMat,classLabelVectordatingDataMat,datingLabels=file2matrix('datingTestSet2.txt')print (datingDataMat)print (datingLabels)import  matplotlibimport matplotlib.pyplot as pltfig=plt.figure()ax=fig.add_subplot(111)ax.scatter(datingDataMat[:,1],datingDataMat[:,2],15.0*array(datingLabels),15.0*array(datingLabels))plt.show()