What does [ ]; do in MATLAB?

Hi, I am looking at some codes. It solves for c at the end,

but it defines c=[]; in the beginning which is like empty matrix.

So what does it do ?

Answer 1

[Image Analyst]

Usually I see that in cases where it must be something because in a loop you're concatenating something onto c. And if c is not defined yet you'll get an error, but it it's something, anything, even null, it's okay. Something like

c = [];
for k = 1 : 5
  c = [c, k];
end

If we didn't define c as null then the c= line inside the for loop would throw an exception the very first time.

Answer 2

[the cyclist]

Empty matrices, scalars, and vectors