vectorize this structure call?

I have failed at trying to vectorize this. Would love some help!

Thanks!

for l = 1:length(tree.Steps.Step)
        wavelength(l) = tree.Steps.Step(l).ATTRIBUTE.Scanning_parameter_value;
        for m = 1:length(tree.Steps.Step(l).Far_field.Order)
            order_num(m,l) =  tree.Steps.Step(l).Far_field.Order(m).ATTRIBUTE.Order_number;
            efficiency(m,l) = tree.Steps.Step(l).Far_field.Order(m).ATTRIBUTE.Efficiency;
        end
    end

[Charlie]

Did you have any success in vectorizing the outside loop?

I am trying to do a similar operation. I am trying the equivalent of cell2mat(tree.Steps.Step) which seems to successfully vectorise these. I am confused why I can put a structure into a matrix though.

Answer 1

[Walter Roberson]

Uggh, but yes it can be done. The following code is partly tested.

for l = 1:length(tree.Steps.Step)
  wavelength(l) = tree.Steps.Step(l).ATTRIBUTE.Scanning_parameter_value;
  temp1 = cell2mat(struct2cell(tree.Steps.Step(l).Far_field.Order));
  temp2 = cell2mat(struct2cell([temp1.ATTRIBUTE]));
  order_num(:,l) = [temp2.Order_number];
  efficiency(:,l) = [temp2.Efficiency];
end

Possibly there are more efficient ways to handle this using structfun().

[Tom]

Thank you! This does remove the inner loop. Any thoughts on removing the outer loop?

[Walter Roberson]

I am not sure at the moment that removing the outer loop is possible, except through techniques such as cellfun(). I have not worked through it.