问Python分组计算

EN

print(dataset)
variable   groups    value  
    Both        I  3099060    
    Both        U   175820    
    C_only      I  5207055    
    C_only      U   225992    
    P_only      I  4063438    
    P_only      U   175593    
      None      I  9413116    
      None      U   292982    

dataset.value.dtype
dtype('int64')
type(dataset)
pandas.core.frame.DataFrame

variable   groups    value     value2
    Both        I  3099060    0.14227
    Both        U   175820    0.20200
    C_only      I  5207055    0.23905
    C_only      U   225992    0.25965
    P_only      I  4063438    0.18654
    P_only      U   175593    0.20174
      None      I  9413116    0.43214
      None      U   292982    0.33661

dataset['value2'] = dataset.groupby(['groups']).value / dataset.groupby(['groups']).value.sum()