Error on custom RNN/LSTM with multiple inputs
I think, input_shape[0] is None. Based on my understanding, you will pass a matrix of size (Batch_size, Time steps, dim of each time step data) to an RNN cell. And while creating your architecture, input_shape[0] will give the batch size (if you mentioned what is the batch size in input layer, if not you will get None). Even if you mention batch size, it will be an integer and you can't index the integers so you are getting that error.