How to perform function whos output is a struct in a loop?

I am trying to loop a data extraction program over multiple files in a string array, and place the results in a struct, but i continue getting the error

Subscripted assignment between dissimilar structures

 GPdata=struct();
 for k=length(files):-1:1
     [GPdata(k)]=extractDataV2(files(k));
 end

how can i get the output of the function to populate subsequent rows of the GPdata struct?

Answer 1

[Stephen23]

Assuming identical fieldnames, the simplest and most robust solution is to concatenate the structure after the loop:

N = numel(files);
C = cell(1,N);
for k = 1:N
    C{k} = extractDataV2(files(k));
end
S = [C{:}]

If you really want to use complex, obfuscated approaches involving indexing into a structure array, see this thread:

https://www.mathworks.com/matlabcentral/answers/12912-how-to-create-an-empty-array-of-structs