python 读取.csv文件数据到数组(矩阵)的实例讲解

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)