Converting this nested for loop for parfor use

I received some really useful help on a similar problem last night here: http://www.mathworks.com/matlabcentral/answers/105436-converting-this-3-nested-for-loop-for-parfor

But this problem is slightly different. I have three local matrices A,B,C that essentially get inserted in the global matrix Aglobal in three separate places. The local matrices themselves will never be split up if you look closely at the code. For example, all three rows and columns of A will always get inserted together in a 3x3 block, but not in the same places as B or C.

    NLoc  = 3;
    nElem = 100;
    nEdge = 300;

    Aglobal = zeros(NLoc*nElem);

    for k=1:nEdge

        index1 = function1(k,...);
        index2 = function2(k,...);

      % A,B, and C are local matrices of dimension 3x3
        [A,B,C] = local_mat(k);

        for i=1:NLoc

            ie = i+(index1-1)*NLoc;

            for j=1:NLoc

                je = j+(index1-1)*NLoc;
                Aglobal(ie,je) = Aglobal(ie,je) + A(i,j);

            end

        end

        for i=1:NLoc

            ie = i+(index2-1)*NLoc;

            for j=1:NLoc

                je = j+(index2-1)*NLoc;
                Aglobal(ie,je) = Aglobal(ie,je) + B(i,j);

            end

        end

        for i=1:NLoc

            ie = i+(index1-1)*NLoc;

            for j=1:NLoc

                je = j+(index2-1)*NLoc;
                Aglobal(ie,je) = Aglobal(ie,je) + C(i,j);

            end

        end

    end

[Matt J]

Are you sure the 2nd inner for loop (the one that uses B(i,j) is right? It shouldn't involve both index1 and index2, similar to the 3rd loop, e.g.,

       for i=1:NLoc
            ie = i+(index2-1)*NLoc;
            for j=1:NLoc
                je = j+(index1-1)*NLoc;
                Aglobal(ie,je) = Aglobal(ie,je) + B(i,j);
            end
        end

[Justin]

Yes, I'm sure that it's correct

Answer 1

[Matt J]

This uses mat2tiles ( Available Here )

   index1=zeros(nEdge1,1);
   index2=zeros(nEdge1,1);
   A=cell(1,nEdge); B=A;C=A;

   csize=[NLoc,NLoc];

   Aglobal = mat2tiles(zeros(NLoc*nElem),csize);

    parfor k=1:nEdge

        index1(k) = function1(k,...);
        index2(k)= function2(k,...);

        [A{k},B{k},C{k}] = local_mat(k);

    end

Aidx=sub2ind(csize,index1,index1);
Bidx=sub2ind(csize,index2,index2);
Cidx=sub2ind(csize,index1,index2);

Aglobal(Aidx)=A;
Aglobal(Bidx)=B;
Aglobal(Cidx)=C;

Aglobal=cell2mat(Aglobal);