"I want to delete the columns of each struct". No, you want to delete the columns of the cell array, if present, contained in the 'bcd' field of each struct. It's important to use proper terminology so you can be understood. It also helps in finding out how to solve the problem:
for siter = 1:numel(E) %iterate over each structure
c = E(siter).bcd; %get cell array in field 'bcd' of structure
if iscell(c) %some structures don't have a cell array in the field
emptycell = cellfun(@isempty, c); %find empty columns of cell array
c(emptycell) = []; %delete empty cell
E(siter).bcd = c; %and put back in structure field
end
end
Or in a more compact form (but slightly more difficult to understand
for siter = 1:numel(E)
if iscell(E(siter).bcd)
E(siter).bcd(cellfun(@isempty, E(siter).bcd)) = [];
end
end
