As per my understanding, you are trying to save leap-seconds in "datetime" object, in such a way that it does not looses precision. You want to pass the date-time string as an input argument to the "datetime" function.
I also faced similiar issue, but tried to resolve it by using the following work-around.
The documentation of "datetime" function (https://www.mathworks.com/help/matlab/ref/datetime.html#d126e365305) say that:
While passing character string as an input argument to the "datetime" function, we can specify the precision upto 9 decimal places by specifing an additional input argument "infmt", as demonstrated below:
DT_string= "2024-01-01T23:59:01.2345678912345Z"; %Same date and time as used in the above question
t = datetime(DT_string,'InputFormat','uuuu-MM-dd''T''HH:mm:ss.SSSSSSSSS''Z')
format longg;
t.Second
This says that the maximum precision available is "9". Therefore, "1.2345678912345" is getting truncated to "1.234567891" in your case. Even if we do not explicitely specify the "inputFormat", it will automatically truncate to the maximum 9 digits after decimal.
Therefore, if you want to retain the precision, the below given command works perfectly.
t=datetime(1972,1,1,23,59,01.2345678912345,'TimeZone','UTCLeapSeconds') % same date and time entered manually
t.Second %This is not truncated
In this case, instead of passing the date-time string, you have to manually enter the the values of year, months, days and time. This is not favourable as mentioned by you.
I am suggesting one of the possible work-around which I implemented in order to pass date-time string and store it in a "datetime" object which supports leap seconds as well as retains precision.
I have made a user defined function "DateTime" which takes the date-time string and returns a "datetime" object. It is demonstrated below:
format longg
ds3 = "01-Jan-2024";
dt3 = "23:59:01.2345678912345";
stringg=(ds3+" "+dt3);
t=DateTime(stringg)
t.Second %this does not losses precision
function out=DateTime(DT_string)
arguments
DT_string string
end
C = textscan(DT_string,'%s %s'); %gives (1 x 2) cell array consisting of date and time
date_string=string(C{1});
time_string=string(C{2});
Date=textscan(date_string,'%f %s %f','delimiter','-'); %save the day, month, year in cell array
Time=textscan(time_string,'%f %f %f','delimiter',':'); %Save hour, minutes and seconds in celll array
DT_object=datetime(date_string);
DT_object.Hour = Time{1}; %extract the hour, minutes and seconds and save them in variable
DT_object.Minute = Time{2};
DT_object.Second = Time{3};
DT_object.TimeZone='UTCLeapSeconds';
out=DT_object;
end
I hope you find this information useful !!
