I am trying to return a 4D array of image data from a function call in MATLAB. I'm not very advanced in MATLAB and I don't know what type of data I have to return from the function. Here is my function:

```
function classimg = loadImages(classdir,ext)
    % create array of all images in directory
    neg = dir([classdir ext]);
    % get size of array (to loop through images)
    numFileNeg = max(size(neg));
    % create a 4D array to store our images
    classimg = zeros(51,51,3,numFileNeg);
    % loop through directory
    for i=1:numFileNeg
        classimg(:,:,:,i) = imread([myDir neg(i).name]);
    end
end

```

Here is the function call:

```
negativeImgs = loadImages("C:\Users\example\Documents\TrainingImages\negatives\","*.jpg");

```

I cannot find any online documentation for the return type? Does anyone know what this would be? `classimg` is populated correctly so the code inner works.