熊猫连接字符串，包括按列分组

Question

我正在尝试对字符串进行分组和连接。我想说的是，我想在串联字符串中包含groupby列。

我已经尝试过下面的代码，并且可以使用！但我担心我这样做的步骤太多。

# Create dataframe
d = {'ORDER_ID': ['order-1','order-2','order-3','order-4','order-5','order-6'], 'pillar_range': ['100','100','100','200','200','300'],'NOTES': ["wet","wet weather","flooded","fine","okay","perfect"]}
df = pd.DataFrame(d)

# Create a concatinated column I want to groupby concatenate in the final step
df['concat_col'] = df['ORDER_ID']+':'+df['NOTES']
# Only select the groupby column and my newly created concatenated column
df = df[['pillar_range','concat_col']]

#  Create the final output
df = df.groupby('pillar_range').agg(lambda x: ' | '.join(set(x)))

Answer 1

好像您将代码切成一行

(df['ORDER_ID']+':'+df['NOTES']).groupby(df['pillar_range']).agg(':'.join)
Out[580]: 
pillar_range
100    order-1:wet:order-2:wet weather:order-3:flooded
200                          order-4:fine:order-5:okay
300                                    order-6:perfect
dtype: object