Batch command on parallel pool with single cell array input argument

I want to run a function on a worker in a parallel pool. I use the batch command for that. Let's say I have the function

function out = some_function(in)
for i = 1:numel(in)
    out{i} = 2*in{i};
end

Now, I want to run this function on a worker. I read the documentation on the batch command and it says to do the following

job = batch(@some_function, 1, { {1, 2, 3} });

However, when I run this command, the job shows the error

"Too many input arguments"

If I instead change the example function to

function out = some_function2(in, in2)
for i = 1:numel(in)
    out{i} = 2*in{i};
end

and run

job = batch(@some_function2, 1, { {1, 2, 3}, [] });

it works correctly.

Why does the first example not work and how can I make it accept the single cell array as input? I expect the problem to be with the nested cell array, but I don't understand why.

Answer 1

[Jori Selen]

For anyone with this question in the future: I found out that the syntax for batch changes when you only have cell arrays as inputs. There is some explanation of this in the documentation of batch and of createTask. So, if all inputs arguments are cell arrays, then we should use

job = batch(@function_handle, N, {{ C1, C2, ..., Cn }})

where C1, C2, ..., Cn are all cell arrays. For my specific example above, the correct syntax is then

job = batch(@some_function, 1, {{{1, 2, 3}}})