Unrecognized function or variable in live script

I am running the following simple live script in Matlab Online:

a = 1
b(2)

function out = b(o)
    out = a + o;
end

and I get the following error:

I am not sure how to make the function b use the variable a in this scenario. One of my postulations was that this is only a Matlab Online issue, but I can't verify this. I also tried using global a but it did not work.

Answer 1

[David Fletcher]

Variables are local to functions. The only (well strictly speaking not the only) way to get them into a function is to pass them in as an argument, and the only way to get them out is to pass them out. In this case you are passing 'o' into the function as an argument, so it is available - a is not being passed into the function so the function can't access it. You would either have to define a inside the function, or pass it into the function as an argument in the same way as you are passing o into the function.

[Jaafar Rammal]

Thanks, this makes sense

[David Fletcher]

Global would work by the way, but you have to also define the global inside the function. I personally would advise against using global variables though

Answer 2

[Walter Roberson]

driver

function driver
  a = 1
  b(2)

    function out = b(o)
       out = a + o;
     end
  end

Shared variables require nested functions.

[Jaafar Rammal]

WORKS AS WELL

Thanks for the answer, neat trick and it works! (unfortunately I can only mark one answer as valid)