numpy 对矩阵中Nan的处理:采用平均值的方法

from numpy import *datMat = mat([[1,2,3],[4,Nan,6]])numFeat = shape(datMat)[1]for i in range(numFeat):  meanVal = mean(datMat[nonzero(~isnan(datMat[:,i].A))[0],i])   #values that are not NaN (a number)  datMat[nonzero(isnan(datMat[:,i].A))[0],i] = meanVal   #set NaN values to mean