Adding hours to time

In my code, i want to state the current time and the time 8 hours later.

function pushbutton8_Callback(hObject, eventdata, handles)
t1 = datestr(now,'HH:MM Am')
t2 = datestr(now,'HH:MM Am') + 8
set(handles.Impt, 'String', sprintf('Your Working Hours will be from %s - %s\n', t1, t2));

the time that is shown in T1 is correct, however im unable to get the T2 value that i wanted. Im currently using MATLAB R2013B.

Answer 1

[Walter Roberson]

datestr() returns a character vector. When you add 8 to it, you are taking the encoding of each character and adding 8 to that '0' becomes 56 ('8'), '1' becomes 57 ('9'), '2' becomes 58 (':'), '3' becomes 59 (';'), ... '9' becomes 65 ('A'), ':' becomes 66 ('B')..

If you want to add 8 hours:

datestr(addtodate(datenum(t1),8,'h'),'HH:MM Am')

You should also consider using datevec instead:

datestr(datevec(t1) + [0 0 0 8 0 0], 'HH:MM Am')

[Kwan Zhao Jie]

Thanks!