numpy的scale就是 x-mean/std

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import numpy as np

from  sklearn import preprocessing

data = np.array([[3, -1.5, 2, -5.4], [0, 4, -0.3, 2.1], [1, 3.3, -1.9, -4.3]])

print(data.mean(axis=0))

print(data.std(axis=0))

data_standardized = preprocessing.scale(data)

print(data_standardized)

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‘’‘以第一列3，0,1为例，其均值为1.333，方差=sqrt((power(3-1.33,2)+power(0-1.33,2)+power(1-1.33,2))/3)=1.247’则标准化为(3-1.333)/1.247=1.3363，大概就是这么一回事情‘’‘