Difference between revisions of "Year-Month-Day-to-Day"
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| − | Sometimes you want to convert a |
+ | Sometimes you want to convert a [https://en.wikipedia.org/wiki/Gregorian_calendar Gregorian] year-month-day to a simple day number, without using system libraries (for example, in embedded code that doesn't have those libraries). |
| − | The following python onliner does that (for days after 1900-02-28 and before 2100-03-01): |
+ | The following python-3 onliner does that (for days after 1900-02-28 and before 2100-03-01): |
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Latest revision as of 21:20, 20 February 2022
Sometimes you want to convert a Gregorian year-month-day to a simple day number, without using system libraries (for example, in embedded code that doesn't have those libraries). The following python-3 onliner does that (for days after 1900-02-28 and before 2100-03-01):
def calcday(y, m, d):
"""
Return days since 2000-01-01
y: year
m: month (1=jan)
d: day (1=first day of month)
"""
return m*30 + 14*m//25+d - (m>2)*(2-(y%4==0))+365*y+(y-1)//4 - 730530
