Python Pandas复制数据框中的行
问题描述：
如果数据如下:
Store,Dept,Date,Weekly_Sales,IsHoliday
1,1,2010-02-05,24924.5,FALSE
1,1,2010-02-12,46039.49,TRUE
1,1,2010-02-19,41595.55,FALSE
1,1,2010-02-26,19403.54,FALSE
1,1,2010-03-05,21827.9,FALSE
1,1,2010-03-12,21043.39,FALSE
1,1,2010-03-19,22136.64,FALSE
1,1,2010-03-26,26229.21,FALSE
1,1,2010-04-02,57258.43,FALSE
我想复制IsHoliday等于TRUE的行，我可以这样做:
And I wanna duplicate rows with IsHoliday equal to TRUE, I can do:
is_hol = df['IsHoliday'] == True
df_try = df[is_hol]
df=df.append(df_try*10)
但是有更好的方法吗，因为我需要将假日行重复5次，如果使用上述方法，则必须追加5次.
But is there a better way to do this as I need to duplicate holiday rows by 5 times, and I have to append 5 times if using above way.
答
您可以将df_try放在列表中，然后执行您要考虑的事情:
You can put df_try inside a list and then do what you have in mind:
>>> df.append([df_try]*5,ignore_index=True)
Store Dept Date Weekly_Sales IsHoliday
0 1 1 2010-02-05 24924.50 False
1 1 1 2010-02-12 46039.49 True
2 1 1 2010-02-19 41595.55 False
3 1 1 2010-02-26 19403.54 False
4 1 1 2010-03-05 21827.90 False
5 1 1 2010-03-12 21043.39 False
6 1 1 2010-03-19 22136.64 False
7 1 1 2010-03-26 26229.21 False
8 1 1 2010-04-02 57258.43 False
9 1 1 2010-02-12 46039.49 True
10 1 1 2010-02-12 46039.49 True
11 1 1 2010-02-12 46039.49 True
12 1 1 2010-02-12 46039.49 True
13 1 1 2010-02-12 46039.49 True