Compatibility with GAP8 nntool about ncps

[mlech26l]

Does the conversion tool nntool support recurrent neural networks?

I am asking because the error seems to be caused by an CONCATENATION op. There is no such op in the LTCCell definition but it is often used to implement RNNs.

Were you able to convert a LSTM or a vanilla RNN with nntool?

[rallen10]

Good question. Let me try to train a vanilla RNN and see if I can make the conversion

[rallen10]

@mlech26l good catch. The same problem arises when I try to use a keras.layers.LSTM model. Therefore it seems the problem is on the gap_sdk/nntool side of things, not keras-ncp. I will close this issue for now; thank you for the help.

For posterity, I tried both keras.layers.LSTM and keras.layers.SimpleRNN, both producing the same error as above (with a slightly different node of CONCATENATION_0_8)

[mlech26l]

Glad I could help