Using the global operator

I have a function below.

As you can see if t==1 I create a vector kk. However, I can not use this kk in the 'else' statement unless I use 'global kk''. Is that correct?

function  [ll  mm]= ssample(e2,t)
    global kk
   
  if t==1
    kk=zeros(T,1);
    for s=1:T 
      kk(s) =...; 
    end
  else
    for s=t:T
      ll =kk(s) ;
    end
   
  end
  mm=kk;
end

[John D'Errico]

I edited your code to fix the indenting and make it readable.

[ektor]

Am I using correctly the global operator?

[Walter Roberson]

We have no reason to expect that t will be 1 before it is anything else.

The correct way to use the global operator is mostly to not use it.

I suspect you should be using

persistent kk
if isempty(kk)
    ... initialize kk here ...
end

[ektor]

I edit my question. t is defined and it starts from t=1. Should I use global?

[Walter Roberson]

We would need the calling code to be sure that t starts at 1.

Better to avoid the matter, such as the way Matt suggests.

Answer 1

[Matt J]

No, you should not use global. Your code should look like this:

function  [ll,  mm, kk]= ssample(e2,t,kk)
...
end