如何为基于另一个DataFrame的字符串创建标签列?

时间:2019-04-01 20:42:59

标签: python pandas

我有以下数据帧

import pandas as pd
df_occurencies = pd.DataFrame({'day':[1,2,3,4,5],
                           'occ':[['frog','wasp','bee'],
                           ['frog','whale','barley','orchid'],
                           ['orchid','barley','frog'],
                           ['orchid','whale','frog'],
                           ['orchid','barley','tulip']]})

df_kingdoms = pd.DataFrame({'item':['frog','wasp','bee',
                              'whale','barley','orchid',
                              'tulip'],
                      'kingdom':['animalia','animalia','animalia',
                              'animalia','plantae','plantae',
                              'plantae']})

我需要设置另一列,根据occ值对df_kingdoms列中的观察结果进行分类。 这些值都是异构的,因此所需的结果将是这样的:

    day                     occ        desired_result
0    1              [frog, wasp, bee]   "animals"
1    2  [frog, whale, barley, orchid]   "animals and plants"
2    3         [orchid, barley, frog]   "mostly plants"
3    4          [orchid, whale, frog]   "mostly animals"
4    5        [orchid, barley, tulip]   "plants"

我知道有很多方法可以解决此问题,但我尝试使用许多.loc定义的函数失败,但我认为这些函数甚至不值得发布。而且我需要在大型数据集上执行此操作,因此速度越快越好。

1 个答案:

答案 0 :(得分:1)

这应该做:

dic_kd={i:j for i,j in zip(df_kingdoms.item,df_kingdoms.kingdom)}
desired_output=[]
for I in df_occurencies.occ:
    list_aux=[dic_kd[i] for i in I]
    if (list_aux.count('animalia')!=0) and (list_aux.count('plantae')==0) :
        desired_output.append('animals')
    elif (list_aux.count('animalia')==0) and (list_aux.count('plantae')!=0) :
        desired_output.append('plants')
    elif list_aux.count('animalia')>list_aux.count('plantae'):
        desired_output.append('mostly animals')
    elif list_aux.count('animalia')<list_aux.count('plantae'):
        desired_output.append('mostly plants')
    else:
        desired_output.append('animals and plants')

df_occurencies['desired output']=desired_output

告诉我如果您什么都不懂,我会帮助您