In the function datenum's formatin, does the 'HH' represent the same as 'hh'?

test2=[1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 25]

newStr=num2str(test2')

num1=datenum(newStr,'hh');

num2=datenum(newStr,'HH');

Answer 1

[Jan]

This is Matlab. Simply try it:

test2=[1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 25];
newStr=num2str(test2');
num1=datenum(newStr,'hh');
num2=datenum(newStr,'HH');
isequal(num1, num2)

ans = logical
   1

Now take a look into the documentation: doc datenum . There is no 'hh" format but only 'HH'. Then Matlab tries to be polite and smart to convert your hh to HH autmatically. Prefer to stay at the documented version.