Access data in two dimensional struct array

I have a struct array with two dimensions:

temp = struct('a',5,'b',7);
bla = repmat(temp,4,8);

I would now like to get the data from one field as a matrix:

data = [bla.a];

However, I now get a vector with all the entries in one dimension. I would like to keep the matrix dimensions, e.g. something like that:

data = zeros(size(bla));
for i=1:size(data,1)
    for j=1:size(data,2)
        data(i,j) = bla(i,j).a;
    end
end

Is there a more elegant way to do this?

Answer 1

[Steven Lord]

There's no guarantee that the field in the elements of a struct array have the same type or size, so making an array may not make sense. The best you could do in general would be to make a cell array and reshape it. That same technique would work with a regular array if all the fields have scalars that can be concatenated, too.

s1 = repmat(struct('x', 1), [3 3]);
for k = 1:numel(s1)
    s1(k).x = k+zeros(k);
end
A = {s1.x}

A = 1×9 cell array
    {[1]}    {2×2 double}    {3×3 double}    {4×4 double}    {5×5 double}    {6×6 double}    {7×7 double}    {8×8 double}    {9×9 double}

B = reshape(A, size(s1))

B = 3×3 cell array
    {[       1]}    {4×4 double}    {7×7 double}
    {2×2 double}    {5×5 double}    {8×8 double}
    {3×3 double}    {6×6 double}    {9×9 double}

check = isequal(B{2, 3}, s1(2, 3).x)

check = logical
   1