Hey Jast,
I understand that you are trying to create a custom layer that itself defines a layer graph. The error provided in the question seems to occur because the layergraph returned by the function 'returnTFBlock' itself does not have a forward method defined.
The error can be resolved by declaring a 'dlnetwork' object as a property of the custom layer and using the object's forward and predict methods. Please refer to the below code snippet for the changes needed to be made in the code for 'transformerBlock' class:
classdef transformerBlock < nnet.layer.Layer & nnet.layer.Formattable % ...
% & nnet.layer.Formattable ... % (Optional)
% & nnet.layer.Acceleratable % (Optional)
% properties
%
% end
properties
Network
end
methods
function obj = transformerBlock( tfName, percentageDropout, layernormEpsilon, numHeads,numKeyChannels, numValueChannels, outputSize )
obj.Name = tfName;
obj.Description = "A transformer block";
lgraph = returnTFBlock( tfName, percentageDropout, layernormEpsilon, numHeads,numKeyChannels, numValueChannels, outputSize );
obj.Network = dlnetwork(lgraph,Initialize=false);
end
function Z = predict(obj,X)
% Predict using network.
net = obj.Network;
dlX = dlarray(X, 'SCB');
net = initialize(net,X);
Z = predict(net,X);
end
function Z = forward(obj,X)
% Forward pass using network.
net = obj.Network;
dlX = dlarray(X, 'SCB');
net = initialize(net,X);
Z = forward(net,X);
end
end
end
You can also refer to the following documentation on 'Network Composition' for more information on the code above:
Hope this answers your query.
