Hi, I am new to Matlab. When typing in a line of code, nested in it is a helper function, can someone assist me with the correct placement of the helper function.unction

This is the line of code:

allTrainLabels = pixelLabelDatastore(trainLabelsPath, classNames, pixelLabelIDs, ReadFcn=@readLabelData);

This is the helper function for ReadFcn=@readLabelData:

function labelData = readLabelData(filename)

rawData = imread(filename);

rawData = imresize(rawData, [350 350]);

labelData = uint8(rawData);

end

Can you show me where do i place the helper function so that the code can be executed without an error.

Thank you

Answer 1

[Sam Chak]

Hi @Augustine

In the past, the convention was to save the helper function as a standalone m-file, typically placed in the same folder as the Main Program (script) file. However, starting from R2016b, it is possible to place the helper function inside a script. In this case, the helper function should be positioned at the end of the file, after the script code.

%% Main Program (script)

...
...
...

% end of script

%% Local function
function y = helper(x)
    ...
end

If the Main Program is implemented as another function file, then the helper function can be placed using the nested approach.

function main
    ...
    ...
    ...
    function y = helper(x)
        ...
    end
end