![](/img/trans.png)
[英]How to transform column values of a dataframe to another dataframe with different indexes?
[英]How to transform a column value of a dataframe with values of another dataframe columns
如何在orig_diff中添加列“ main_category”,該列將指示子類別屬於哪個主要類別。 例如,值“電影”的orig_df必須將“ main_category”作為“娛樂”,將“ Maths”作為“教育”。
import pandas as pd
import numpy as np
orig_df = pd.DataFrame({"sub_cat" : ["Movie", "Science", "Maths", "Music", "Songs", "Dance", "English", "Maths", "Songs"], "Student": ["Stud1", "Stud2", "Stud3", "Stud4", "Stud5", "Stud6", "Stud7", "Sud8", "Stud9"]})
sub_df = pd.DataFrame({"Education": [0,1,1,0,0,0,1], "Entertainment": [1,0,0,1,1,1,0]}, index=["Movie", "Science", "Maths", "Music", "Songs", "Dance", "English"])
print(orig_df)
print(sub_df)
一種方法是通過迭代行從sub_df
創建字典。
然后使用字典作為orig_df['sub_cat']
上的地圖:
d = {idx: next(k for k in sub_df if row[k]==1)
for idx, row in sub_df.iterrows()}
orig_df['main_category'] = orig_df['sub_cat'].map(d)
print(orig_df)
Student sub_cat main_category
0 Stud1 Movie Entertainment
1 Stud2 Science Education
2 Stud3 Maths Education
3 Stud4 Music Entertainment
4 Stud5 Songs Entertainment
5 Stud6 Dance Entertainment
6 Stud7 English Education
7 Sud8 Maths Education
8 Stud9 Songs Entertainment
請注意,這假定每個sub_cat
僅映射到“教育”或“娛樂”之一。
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.