Get week start date(Monday or Sunday) from week number of the month-CodePudding

I have data that has date column in this format 'Mar Wk 4 2022', where Mar signifies the month that is 'March', 'Wk 4' signifies the week of the month (values ranging from 1 to 5) and '2022' signifies the year,

is there a way to get week start date (Monday) of that week, i.e.,. 4th week of March, 2022?

CodePudding user response：

You can add ' Mon' (for Monday) to your strings, and convert using pandas.to_datetime with the %b Wk %U %Y %a format:

df['start_date'] = pd.to_datetime(df['date'] ' Mon', format='%b Wk %U %Y %a')

output:

            date start_date
0  Mar Wk 4 2022 2022-01-24

used input:

df = pd.DataFrame({'date': ['Mar Wk 4 2022']})

CodePudding user response：

If 'week' of the month is:

week 1:  1st - 7th
week 2:  8th - 14th
etc.

it'll depend purely on the day of the 1st of the month so if it's 'Monday', the result will be week * 7 - 6. If it's Tuesday, it'll be 'week * 7', Wednesday will be 'week * 7 - 1' etc.

I don't know numpy, but assume you can get the day as 'Tue' etc. given a day, month and year. So, with appropriate variables the answer is...

monday = week * 7 - ["Tue", "Wed", "Thu", "Fri", "Sat", "Sun", "Mon"].index(day)