Returns the day number of a given date.
See this note.
int Day(double d[, int n])
If it is a Julian days date, return the real value of day in a date(Julian days) value, 1 to 31 or 1 to 366.
If it is not a Julian days date, return -1.
int aa = Day(2454827.5982639, 2);
aa = ;//Should return the day of this time, 362.
Year, Month, Hour, Minute, Second, Now