pandas处理丢失数据：import pandas as pd import numpy as np dates = pd.date_range('20190529', periods=4) df = pd.DataFrame(np.arange(16).reshape((4, 4)), index=dates, columns=['A', 'B', 'C', 'D']) df.ilo...
pandas设置值：import pandas as pd import numpy as np dates = pd.date_range('20190529', periods=4) df = pd.DataFrame(np.arange(16).reshape((4, 4)), index=dates, columns=['A', 'B', 'C', 'D']) # 根据索引修改 ...
pandas选择数据：import pandas as pd import numpy as np dates = pd.date_range('20190524', periods=6) df = pd.DataFrame(np.arange(24).reshape((6, 4)), index=dates, columns=['A', 'B', 'C', 'D']) print(df)...
pandas基本介绍：import pandas as pd import numpy as np s = pd.Series([1, 3, 6, np.nan, 44, 1]) print(s) """ 0 1.0 1 3.0 2 6.0 3 NaN 4 44.0 5 1.0 dtype: float64 &qu...
Numpy的copy & deep copy：import numpy as np a = np.array([1, 2, 3, 4]) b = a b[2] = 33 # 同时也改变了a print(a) # [ 1 2 33 4] c = a.copy() c[2] = 3 # 不会改变a print(a) # [ 1 2 33 4] print(c) # [1 2...