Converting time_duration to DATE

Question

I want to convert a time_duration to a DATE format, which is the number of days since 1899, 12, 30.

DATE date_from_duration(time_duration td)
{
   double days =          


        

Answer 1

I might be missing some of the complexity, but it seems really simple to me:

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#include 
#include 
using DATE = double;

boost::posix_time::ptime pTime_from_DATE(double date)
{
    static const boost::posix_time::ptime::date_type base_date(1899, boost::gregorian::Dec, 30);
    return boost::posix_time::ptime(
            base_date, 
            boost::posix_time::milliseconds(date * 1000 * 60 * 60 * 24));
}

int main() {
    boost::posix_time::time_duration duration(1007645, 15, 0);

    DATE date = duration.total_milliseconds() / 1000.0 / 60 / 60 / 24;

    std::cout << date << ": " << pTime_from_DATE(date);
}

Prints

41985.2: 2014-Dec-12 05:15:00

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