how to correct NaT in datetime

when i do as

st = datetime('13:00:00');
et = datetime('14:00:00');
t = datetime(cellTime);
tp = isbetween(t, st, et);

i have time between 13 and 14 in my cell array named cellTime, but when i process it as below,

 t = datetime(cellTime, 'Format', 'hh:mm:ss');

i get all time after, 12pm as "NaT" i wanted to do as

 t = datetime(cellTime, 'Format', 'hh:mm:ss');

because i need only the time value, if i dont use format, the date also comes, and that too todays date... any method to get only time and correct the NaT

[Walter Roberson]

What is the format of the entries in cellTime ?

Answer 1

[Steven Lord]

According to the definition of the Format property, 'hh' means "Hour, 12-hour clock notation using two digits". Instead you want to use 'HH', which means "Hour, 24-hour clock notation using two digits". Compare these two variables:

dt1 = datetime({'10:30', '15:36'}, 'InputFormat', 'hh:mm')
dt2 = datetime({'10:30', '15:36'}, 'InputFormat', 'HH:mm')

Answer 2

[Walter Roberson]

 t = datetime(cellTime, 'InputFormat', 'hh:mm:ss', 'Format', 'hh:mm:ss');

[Elysi Cochin]

sir i read the time for an excel sheet to matlab... After reading i convert to datetime, if i give as

t = datetime(cellTime);

the time after 12:00 pm to 23:59 will be read corrrectly... but as i do not have given the date, todays date will be read.

but if i select only the time from the datetime using

t = datetime(cellTime, 'InputFormat', 'hh:mm:ss', 'Format', 'hh:mm:ss');

or 

t = datetime(cellTime, 'Format', 'hh:mm:ss');

the date is not coming, that is correct, but the time after 12:00 pm to 23:59 will be NaT... i dont know why it is happening.... my excel data has more than 100 column values... but in a small cell array with 5 values, it is coming correctly.... i am not able to correct the error NaT