Deyire, unless you're using a pretty old version of MATLAB, use datetime and duration instead of datestr/datenum/datevec. Also your code doesn't look like it computes time differences, it computes milliseconds since year zero. Try this:
>> t0 = datetime('now'); pause(rand); t1 = datetime('now'); >> milliseconds(t1 - t0) ans = 453.54
I suggest that in your loop, you save all the timestamps, as datetimes, and all the data at each timestamp, and then ONCE, outside the loop, create a timetable something like this:
dt = diff(timestamps); dt.Format = 's';
tt = timetable(data(2:end),'RowTimes',dt)
