Sum of next n rows in python - python-3.x

Question

I have a dataframe which is grouped at product store day_id level Say it looks like the below and I need to create a column with rolling sum
prod store day_id visits
111 123 1 2
111 123 2 3
111 123 3 1
111 123 4 0
111 123 5 1
111 123 6 0
111 123 7 1
111 123 8 1
111 123 9 2
need to create a dataframe as below
prod store day_id visits rolling_4_sum cond
111 123 1 2 6 1
111 123 2 3 5 1
111 123 3 1 2 1
111 123 4 0 2 1
111 123 5 1 4 0
111 123 6 0 4 0
111 123 7 1 NA 0
111 123 8 1 NA 0
111 123 9 2 NA 0
i am looking for create a
cond column: that recursively checks a condition , say if rolling_4_sum is greater than 5 then make the next 4 rows as 1 else do nothing ,i.e. even if the condition is not met retain what was already filled before , do this check for each row until 7 th row.
How can i achieve this using python ? i am trying
d1['rolling_4_sum'] = d1.groupby(['prod', 'store']).visits.rolling(4).sum()
but getting an error.

Answer 1

The formation of rolling sums can be done with rolling method, using boxcar window:
df['rolling_4_sum'] = df.visits.rolling(4, win_type='boxcar', center=True).sum().shift(-2)
The shift by -2 is because you apparently want the sums to be placed at the left edge of the window.
Next, the condition about rolling sums being less than 4:
df['cond'] = 0
for k in range(1, 4):
df.loc[df.rolling_4_sum.shift(k) < 7, 'cond'] = 1
A new column is inserted and filled with 0; then for each k=1,2,3,4, look k steps back; if the sum then less than 7, then set the condition to 1.