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timeleap-year

Is there library to convert number of days in a specific year to month and date?

I have an information which contains specific year and number of days. For example, 2000137 means May 16, 2000 because May 16 is the 137th day of year 2000. I need those numbers like 2000137 in the format 2000-05-16. I can do such conversion by considering how many days are in each month and how many days are in each year but I need to take the leap years into consideration and it seems too tedious to implement such code. I wonder if there is simple function in Excel or Python to do such conversion.

Solution

  • You can achieve the above using Python's fromordinal and toordinal functions in the datetime library.

    Try the following:

    from datetime import date
ip=2000137
year=ip//1000
days=ip%1000
#days until that year
days_till_year=date(year,1,1).toordinal()
days_till_input=days_till_year+days-1
print(date.fromordinal(days_till_input))

    The output would be:

    2000-05-16