最近在学习这本书，按照书上的实例编写了knn.py的文件，使用canopy进行编辑，用shell交互时发现运行时报错：
>>> kNN.classify0([0,0],group,labels,3)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
NameError: name 'kNN' is not defined
运行的代码如下：
from numpy import *
import operator def createDataSet():
group = array([[1.0,1.1],[1.0,1.0],[0,0],[0,0.1]])
labels = ['A','A','B','B']
return group,labels def classify0(inX,dataSet,labels,k):
dataSetSize = dataSet.shape[0]
diffMat = tile(inX,(dataSetSize,1)) - dataSet
sqDiffMat = diffMat**2
sqDistances = sqDiffMat.sum(axis = 1)
distances = sqDistances**0.5
sortedDistIndicies = distances.argsort()
classCount = {}
for i in range(k):
voteIlabel = labels[sortedDistIndicies[i]]
classCount[voteIlabel] = classCount.get(voteIlabel,0) + 1
sortedClassCount = sorted(classCount.iteritems(),
key=operator.itemgetter(1),reverse=True)
return sortedClassCount[0][0]
然后我在canopy中重新关闭程序，又打开后，就可以运行成功了
import kNN group,labels=kNN.createDataSet() kNN.classify0([,],group,labels,)
还有一点是文件名不识别大小写 需要注意