Screen shots are probably not the most convenient way for others to diagnose this problem.
You haven't lost a millisecond, you never had it to begin with. Here's the deal:
>> dv = [2015 8 13 21 6 19.172; 2015 8 13 21 6 19.180]
dv =
2015 8 13 21 6 19.172
2015 8 13 21 6 19.18
You only think that last value is 19.18. It isn't. It's the floating point value that's closest to 19.18, which happens to be just less than the real number 19.18. The display simply shields you from that. With "numbers", that's probably what you'd want display to do, but in "time", you'd probably be unhappy if the display for something just before midnight rounded up to the next day. So:
>> dt = datetime(2015,8,13,21,6,[19.172 19.180],'Format','dd-MM-yyyy HH:mm:ss.SSSSSS')
dt =
13-08-2015 21:06:19.172000 13-08-2015 21:06:19.179999
Your problem is that by the time you've typed "19.18", you're done for. datetime has the precision to give you what you want, though:
>> dt = datetime('13-08-2015 21:06:19.180','Format','dd-MM-yyyy HH:mm:ss.SSSSSS')
dt =
13-08-2015 21:06:19.180000
>> dt = datetime(2015,8,13,21,6,19,[172 180],'Format','dd-MM-yyyy HH:mm:ss.SSSSSS')
dt =
13-08-2015 21:06:19.172000 13-08-2015 21:06:19.180000
