In[]:=
dec=NetDecoder[{"Class",{1,2,3}}];​​lin=NetInitialize[LinearLayer[3,"Input"->2]];​​NN=NetChain[{lin,SoftmaxLayer[]},"Output"->dec];​​NN[{x,y}]​​
NetChain
:Data supplied to port "Input" was not a length-2 vector (or a list of these).
Out[]=
$Failed