append value of next row with current row pandas groupby id

Question

I have a dataframe as

id status
1  owner
1  retail
1  shop
1  customer
2  owner
2  retail

I created new column of Last status like

id status   Last status
1  owner     NA
1  retail    owner
1  shop      retail
1  customer  shop
2  owner     NA
2  retail    owner

But I want to create a column of the flow ie append last status with the next value like

id status   From To
1  owner     NA
1  retail    owner -> retail
1  shop      retail -> shop
1  customer  shop -> customer
2  owner     NA
2  retail    owner -> retail

Big Thanks in advance

Answer 1

尝试：

df['From to'] = df['last status'] + '->' + df['status']

Answer 2

Let's do groupby + shift and concatenate with status column:

df['From to'] = df.groupby('id')['status'].shift() + ' -> ' + df['status']

---

   id    status           From to
0   1     owner               NaN
1   1    retail   owner -> retail
2   1      shop    retail -> shop
3   1  customer  shop -> customer
4   2     owner               NaN
5   2    retail   owner -> retail