Create a rolling date list in Excel - excel

Question

I want to create a rolling list of dates in Excel like so:
Day Date
Day 1 01-Jul-19
Day 1 02-Jul-19
Day 1 03-Jul-19
Day 1 04-Jul-19
Day 1 05-Jul-19
Day 1 06-Jul-19
Day 1 07-Jul-19
Day 2 02-Jul-19
Day 2 03-Jul-19
Day 2 04-Jul-19
Day 2 05-Jul-19
Day 2 06-Jul-19
Day 2 07-Jul-19
Day 2 08-Jul-19
Day 3 03-Jul-19
Day 3 04-Jul-19
Day 3 05-Jul-19
Day 3 06-Jul-19
Day 3 07-Jul-19
Day 3 08-Jul-19
Day 3 09-Jul-19
Day 4 04-Jul-19
. .
. .
. .
So essentially what's happening is that the 7-day range moves forward by one day each time, from a specific start date (in the example above, 01-07-19) until it reaches an end date. Is there an automated way of doing this?

Answer 1

#ashvin10 you can do this in vba, but you can also accomplish this with 2 formulas without using vba at all, here's how:
for illustration purposes we'll just assume you are starting with 07/01/2019 on the first row and your information will be displayed in columns A and B.
in A1 enter the string Day 1
in B1 enter your starting date, like 07/01/2019
in A2 enter this formula: ="Day " & IF(MOD(ROW(A2),7)<>0, MID(A2,5,(LEN(A2)-4)), MID(A2,5,(LEN(A2)-4))+1)
in B2 enter this formula: =IF(A2=A1,B1+1,OFFSET(B2,-7,0)+1)
highlight cells A2 and B2
click on the cross that becomes available on the bottom right hand corner of cell B2
drag down the formula till you hit the end date you desire
the cells are populated with the values you requested in the format you requested
If you absolutely have to have it done using vba please let me know and I can show you how to do it that way as well, but this way is much easier.
EDIT: #ashvin10 I'm so sorry, the original formula I instructed you to put into A2 only works for Day 1 through Day 9, if you go into days past 9 it won't display correctly. I've fixed the formula that should be pasted into A2 so now it will work no matter how many days you go down. I'm so sorry for the confusion.

Answer 2

Alternatively, this can also be done in Python.
import datetime
start_date = '01-07-2019'
end_date = '31-01-2020'
output_file_name = 'rolling dates'
output_file_extension = '.CSV'
delimiter = '\t'
with open((output_file_name + output_file_extension.lower()), 'w+') as file:
header = "Day" + delimiter + "Date" + '\n'
file.write(header)
start_date_object = datetime.datetime.strptime(start_date, '%d-%m-%Y').date()
end_date_object = datetime.datetime.strptime(end_date, '%d-%m-%Y').date()
number_of_days = abs((end_date_object - start_date_object).days)
next_day = start_date_object
for i in range(1, number_of_days + 2):
for j in range(7):
file.write(("Day {0}" + delimiter + next_day.strftime('%d-%m-%Y') + '\n').format(i))
next_day += datetime.timedelta(days=1)
start_date_object += datetime.timedelta(days=1)
next_day = start_date_object
After running the code above, I simply created a blank Excel file and then imported the data from the CSV file output by this code.
This is arguably more complicated than #gharbad-the-weak's answer but thought I'd include this anyway.