Problem in using datetime

Hi, I have timestamp in the form of strings, for e.g.

e =

  1×1 cell array

    {'8-3-2021 9-03-51 PM'}

However, when I use the following code to comvert it into "datetime" format, I end up with this :

new1 = datetime(e, 'InputFormat', 'M-d-yyyy H-mm-ss a', 'Format', 'yyyy-M-d H-mm-ss a');
new1(isnat(new1)) = datetime(e(isnat(new1)), 'InputFormat', 'M-d-yyyy H-mm-ss a');

I also get the warning :

Warning: The format 'M-d-yyyy H-mm-ss a' contains fields for 24 hour of day (H) and for day period (a). This will cause unexpected results when converting from text. See the
datetime.Format property for a complete description of the identifiers used in datetime formats. 

>> new1

new1 = 

  datetime

   2021-8-3 12-03-51 PM

I tried different things but could not fix it.

I don't quite understand why the time changes to 12 at the hour position from the original 9.

Any help is much appreciated.

[Sebastiano Marinelli]

I think the problem is in using the capital "h" try this code should work:

e = {'8-3-2021 9-03-51 PM'};
new1 = datetime(e, 'InputFormat', 'M-d-yyyy h-mm-ss a', 'Format', 'yyyy-M-d h-mm-ss a');
new1(isnat(new1)) = datetime(e(isnat(new1)), 'InputFormat', 'M-d-yyyy h-mm-ss a');

Proably using the capital H means that you use the 24h format not the 12 format. Let me know if it works

[Agnivo Gosai]

Thanks, this works

Answer 1

[Dave B]

The H in your format is referring to a 24-hour clock hour, as in 14 to represent 2pm, but that doesn't make sense as you're also specifying "PM". I suspect you need to change this to a lowercase h.