How to apply a function to all rows of a field in a structure?

In my script a structure's field is created the following way:

 omleszt(1).N = length(omleszt(1).out);
 omleszt(2).N = length(omleszt(2).out);
 omleszt(3).N = length(omleszt(3).out);
 omleszt(4).N = length(omleszt(4).out);

And the same goes on with many other fields of omleszt. Because of this writing the script became a tedious and long task. Is there a way to apply the function to all the rows of a field with a single command? Like for example (I know this does not work):

 omleszt.N = length(omleszt.out)

Answer 1

[Walter Roberson]

T = cellfun(@length, {omleszt.out}, 'Uniform', 0);
[omlestzt.N] = T{:};

[Tibor Guba]

It works! Thank you!