As the question has been left unanswered, for future readers of the questions:
The documentation you link gives the answer to your question.
Given the fact you have a pre-trained model as you say:
YPred = classify(netTransfer,testDigitData);
where netTansfer
is the pre-trained model and testDigitData
is your test image that you want to predict the label.
Your image(s) need to be loaded following the instruction also given in the documentation:
digitDatasetPath = fullfile(matlabroot,'toolbox','nnet','nndemos', ...
'nndatasets','DigitDataset');
digitData = imageDatastore(digitDatasetPath, ...
'IncludeSubfolders',true,'LabelSource','foldernames');
(digitData
will become testDigitData
if the images that you load are for testing purpose only, which seems to be your case)
testDigitData
in the example from the link you give. The CNN is trained ontrainDigitData
. $\endgroup$