function [TotalDays, Flag_Leap_Year] = MyTotalDays(yyyy,mm,dd)
% ¼ÆËãµ±ÄêÊÅÈ¥ÌìÊý
% Ò²¿ÉÓÃMatlab¿âº¯Êýdaysdif¼ÆË㣺daysdif('01/01/2015','11/04/2015',0)
% datenumÒ²¿É¡£
Year = yyyy;
Month = mm;
Day = dd;
% ½¨ÒéÔö¼ÓÄêÔÂÈÕÊý¾ÝºÏ·¨ÐÔÅжÏ
% ÅжÏÊÇ·ñΪÈòÄê
% 1. Äܱ»400Õû³ýµÄÄêΪÈòÄê
% 2. ²»Äܱ»400Õû³ýµ«Äܱ»100Õû³ýµÄÄ겻ΪÈòÄê
% 3. ²»Äܱ»100Õû³ýµ«Äܱ»4Õû³ýµÄÄêΪÈòÄê
% 4. ÆäÓàµÄÄê·Ý²»ÎªÈòÄê
Flag_Leap_Year = 0;
if rem(Year,400) == 0
    Flag_Leap_Year = 1;
elseif rem(Year,400) ~= 0 && rem(Year,100) == 0
    Flag_Leap_Year = 0;
elseif rem(Year,100) ~= 0 && rem(Year,4) == 0
    Flag_Leap_Year = 1;
else
    Flag_Leap_Year = 0;
end
TotalDays = 0;
for i = 1:mm-1
    TotalDays = TotalDays + MyMonth(i, Flag_Leap_Year);
end
TotalDays = TotalDays + Day;

end

function Days = MyMonth(Month,IsLeapYear)
% ¼ÆËã¸ø¶¨Ô·ÝÌìÊý
Days = 0;
if Month == 2
    Days = 28*(~IsLeapYear) + 29*IsLeapYear;
elseif Month == 4 || Month == 6 || Month == 9 || Month == 11
    Days = 30;
else
    Days = 31;
end
end

2Â¥: Originally posted by mygt_hit at 2015-11-04 23:48:48
function  = MyTotalDays(yyyy,mm,dd)
% ¼ÆËãµ±ÄêÊÅÈ¥ÌìÊý
% Ò²¿ÉÓÃMatlab¿âº¯Êýdaysdif¼ÆË㣺daysdif('01/01/2015','11/04/2015',0)
% datenumÒ²¿É¡£
Year = yyyy;
Month = mm;
Day = dd;
% ½¨ÒéÔö¼ÓÄêÔÂÈÕ ...