pandas pivot_table保持索引

Question

我有一个数据帧:

   day_bucket  label  numeric_value
0  2011-01-21  birds              4
1  2011-01-22  birds              0
2  2011-01-23  birds              7
3  2011-01-24  birds              3

我想透过这个数据帧,以便我有一个列birds低于它的列.

pd.pivot_table(df, values='numeric_value', index='day_bucket',columns='label')  

得到:

label       birds
day_bucket             
2011-01-21  4
2011-01-22  0
2011-01-23  7
2011-01-24  3

我应该怎么做保持索引？结果如下:

    day_bucket birds    
0   2011-01-21  4
1   2011-01-22  0
2   2011-01-23  7
3   2011-01-24  3 

Answer 1

与此同时，我也得出了一个结果

pd.pivot_table(df, values='numeric_value', 
                   index=[df.index.values,'day_bucket'],
                   ,columns='label').reset_index('day_bucket')

label  day_bucket  mortality_birds
0      2011-01-21                4
1      2011-01-22                0
2      2011-01-23                7
3      2011-01-24                3

Answer 2

set_index 同 append

df.set_index(['day_bucket', 'label'], append=True) \
  .rename_axis([None, None, None]).squeeze().unstack()