pandas groupby

示例数据

speed   lightning   age gender  veg exercise    muscle  stress  heart
0   284.040436  1   55.380070   1   0   4.209747    5.662490    7.896281    103.698022
1   272.883412  1   26.843615   0   0   0.755541    4.902595    8.128346    99.604275
2   297.942469  1   45.985247   1   1   4.842116    2.292441    4.560554    108.767159
3   262.623727  0   49.089562   0   1   2.602956    7.040869    9.419283    95.496679
4   286.559119  0   39.459594   1   1   9.625364    2.955399    7.704228    104.223158

groupby

用法一

df['speed'].groupby(df['lightning']).mean()

结果：

lightning
0    300.857047
1    299.980910

用法二

df.groupby('lightning')['exercise', 'age', 'stress', 'gender', 'muscle', 'veg', 'heart'].agg(['mean'])

结果：

      exercise  age         stress      gender        muscle    veg     heart
      mean      mean        mean          mean        mean      mean    mean
lightning                           
0   5.925047    27.192573   4.964066    0.491629    5.609706    0.812589    109.402687
1   4.412330    42.338834   4.988935    0.500285    4.548425    0.760146    109.492677