import numpy 
my_matrix = numpy.loadtxt(open("1.csv","rb"),delimiter=",",skiprows=0) 

numpy.savetxt('2.csv', my_matrix, delimiter = ',')

SyntaxError: (unicode error) 'unicodeescape' codec can't decode bytes in position

> import pandas as pd
> df = pd.read_csv('D:\Python\\l\B_train1.csv')
> df.values
> df.as_matrix(columns=None)

> testB = test[test.intersection_id.isin(["B"])]
> pd.DataFrame.to_csv(testB,"D:\Python\\k\\t5B.csv")
#testB是个dataFrame

> m = df.as_matrix(columns=None)
> from sklearn.preprocessing import Imputer
> imp = Imputer(missing_values='NaN', strategy='mean', axis=0)
> imp.fit(m)
Imputer(axis=0, copy=True, missing_values='NaN', strategy='mean', verbose=0)
> imp.transform(m)