MATLAB: Using ‘plotResiduals’ in a for loop.. is it possible to using indexing to store the results and plot then together

curve fittingfor loopindexindexingMATLABnonlinear

I have a series of data fits I've performed using 'fitnlm' which I've acquired using a for loop like so.
    fittables = cell(1, numel(files));
    modelfun = @(sigma,x) exp(-x.^2 / (2 * sigma));
for k = 1:length(files)
    table{k} = table(x{k}, y{k}, 'VariableNames', {'x', 'y'});
    beta0 = 1; 
    mdl{k} = fitnlm(table{k}, modelfun, beta0);
end
I want to use the 'plotResiduals()' function to plot the residuals of each of these fits onto one graph. I can get it to work on a single fit but I can't work out how to index the function. I've tried the following two ways..
residuals{k} = plotResiduals(mdl{k},'caseorder');
which will run but it just overwrites the plot with each iteration,
and 
residuals(k) = plotResiduals(mdl(k),'caseorder');
which results in the error "Undefined function 'plotResiduals' for input arguments of type 'cell' ".
Is there any way to plot these residuals on the same plot within the for loop? Indexing doesn't seem to be working.

Best Answer

It appears that plotResidual respects "hold on" for other than probability plots. You can create the probability plot directly using normplot, and not using probplot or plotResiduals. For example:
load carsmall
tbl = table(MPG,Weight);
tbl.Year = categorical(Model_Year);
mdl = fitlm(tbl,'MPG ~ Year + Weight^2');
normplot(mdl.Residuals.Raw); 
hold on; 
h1= plotResiduals(mdl)
Related Question