Nested for-Loops in parfor

I try to put a for-loop in a parfor-loop. However, the following code is invalid.

parfor i=1:10
  for j=1:10
   a(j)=1;
  end
end

The only way I know to fix that is

parfor i=1:10
  for j=1:10
   a(i,j)=1;
  end
end

But I think it is inefficient when the size of "a" is large (I don't need "a" at the end of this program) . Is there a better way to implement this nested for-loop?

[Edric Ellis]

@Walter Roberson has provided you with a way to fix the problem. Just to explain the problem a little bit more - parfor insists on being able to prove that the iterations of your parfor loop are not (trying to be) order-dependent. In your original code, it appears as though the value of a as assigned when i==1 is still available on the next iteration when i==2. Walter's fix assigns a value to the whole of a, and this makes parfor satisfied that you cannot possibly access the old values of a in subsequent iterations.

Answer 1

[Walter Roberson]

parfor i=1:10
  a = zeros(10, 1);
  for j=1:10
    a(j)=1;
  end
end

[LD]

thanks