It does not come clear to me how the seq_length
is not the exact same as the hidden_size
in LSTMs.
For example, in the next image, the seq_length
is T since there are $x_{1}, x_{2}, ..., x_{T}$ time steps and there are is one LSTM cell (green LSTM blocks) per input $x_{i}$. So in this image seq_length
== hidden_size

In addition, every LSTM cell requires 3 inputs:
- $x_{t}$ the input value at time t.
- $h_{t-1}$ the hidden state value from the previous time step.
- $c_{t-1}$ the cell state value from the previous time step.
This can be seen in the following image:

How can the hidden_size
be lower or higher than the seq_length
? In any of both cases the LSTM cells would not have the $x_{i}$ input which is required.