How to convert a python datetime.datetime to excel serial date number

Question

I need to convert dates into Excel serial numbers for a data munging script I am writing. By playing with dates in my OpenOffice Calc workbook, I was able to deduce that \'1

Answer 1

if the problem is that we want DATEVALUE() excel serial number for dates, the toordinal() function can be used. Python serial numbers start from Jan1 of year 1 whereas excel starts from 1 Jan 1900 so apply an offset. Also see excel 1900 leap year bug (https://support.microsoft.com/en-us/help/214326/excel-incorrectly-assumes-that-the-year-1900-is-a-leap-year)

def convert_date_to_excel_ordinal(day, month, year) :

    offset = 693594
    current = date(year,month,day)
    n = current.toordinal()
    return (n - offset)