MATLAB: Fopen syntax, a new usage??

Question

i found a usage of fopen which is not found in MATLAB documentations

here is my code

s = 'name';
fileID = fopen([s,'.txt'],'w');

this syntax really works. but i could not found the source.

the ordinary usage of fopen could be

fileID = fopen('name.txt','w')

why?

is MATLAB documentation uncomplete?

thank you!

Answer 1

It’s not so complicated [] is used for concatenation

 ['name', '.txt'] % try it in command window and see what happens