How can i preallocate memory for sliced output variables in parfor loop?

How can i preallocate memory for sliced output variables in a parfor loop? Following is the example mentioned in Matlab Parallel Computing toolbox. The array "b" in the example is the sliced output variable. But, there is no preallocation of memory for "b". Isn't that going to affect the performance of Matlab in parfor loop?

a = 0;

z = 0;

r = rand(1,10);

parfor ii = 1:10

     a = ii;

     z = z + ii;

     b(ii) = r(ii);

end

Thanks.

Answer 1

[Matt J]

Why not just pre-allocate b prior to the parfor loop?

    a = 0;
    z = 0;
    r = rand(1,10);
    b=zeros(size(r));

    parfor ii = 1:10

     ....

    end,