我有以下DF
ID, 1, 2, 3 #Columns
0,Date, Review, Average, Review # Observations
1,01/01/18 2, 4, 3 # Date and Review Score
2,02/01/18 1, 2, 4 #Date and Review Score
我正在尝试将此DF分解为以下内容,使用以下代码将我关闭:
df = pd.melt(df,id_vars=['ID'],var_name=['Store'],value_name='Score').fillna(0).set_index('ID')
此程序:
Store Score
ID
Date
01/01/18 1 Review
01/01/18 1 2
02/01/18 1 1
我想做的是删除“评论”并将其放在自己的列中,如下所示:
Store Review Type Score
ID
Date
01/01/18 1, Review, 1
02/01/18 1, Review, 2
我尝试做宽到长的操作,但是我认为我需要在这里使用某种程度的多索引,否则我可能会考虑过度。
注意事项:
我的DF长824列,324行 我的变量是按行排列的,沿着日期,以ID为列标题。
答案 0 :(得分:1)
如果我了解您在寻找什么...
从此数据帧开始,我相信您所拥有的是
ID 1 2 3
0 Date Review Average Review
1 01/01/18 2 4 3
2 02/01/18 1 2 4
假设您完成了pd.melt()
,然后留下了:
new_df = pd.melt(df,id_vars=['ID'],var_name=['Store'],value_name='Score').fillna(0).set_index('ID')
Store Score
ID
Date 1 Review
01/01/18 1 2
02/01/18 1 1
Date 2 Average
01/01/18 2 4
02/01/18 2 2
Date 3 Review
01/01/18 3 3
02/01/18 3 4
然后您可以执行以下操作:
# sort index so all the 'Date' values are at the bottom
new_df.sort_index(inplace=True)
# create a new df of just the dates becuase that is your review types
review_types = new_df.loc['Date']
# rename column to review types
review_types.rename(columns={'Score':'Review Type'}, inplace=True)
# remove new_df.loc['Date']
# new_df = new_df.drop(new_df.tail(len(review_types)).index).reset_index()
# UPDATED removal of new_df.loc['Date']
# I recommend removing the date values by doing this and not using .tail()
new_df = new_df[~new_df.index.str.contains('Date')].reset_index()
# rename ID column to Date
new_df.rename(columns={'ID':'Date'}, inplace=True)
# merge your two dataframes together
new_df.merge(review_types, on='Store')
为您提供:
Date Store Score Review Type
0 01/01/18 1 2 Review
1 02/01/18 1 1 Review
2 01/01/18 2 4 Average
3 02/01/18 2 2 Average
4 01/01/18 3 3 Review
5 02/01/18 3 4 Review