title: ValueError: The two structures don't have the same number of elements
body: <pre><code>with tf.variable_scope('forward'):
    cell_img_fwd = tf.nn.rnn_cell.GRUCell(hidden_state_size, hidden_state_size)
    img_init_state_fwd = rnn_img_mapped[:, 0, :]
    img_init_state_fwd = tf.multiply(
        img_init_state_fwd, 
        tf.zeros([batch_size, hidden_state_size]))
    rnn_outputs2, final_state2 = tf.nn.dynamic_rnn(
        cell_img_fwd, 
        rnn_img_mapped, 
        initial_state=img_init_state_fwd, 
        dtype=tf.float32)
  </code></pre>
  
  <p>This is my code for a GRU for input of dimension 100x196x50, it should be unpacked along the second dimension (that is 196). <code>hidden_state_size</code> is 50, <code>batch_size</code> is 100. However I get the following error: </p>
  
  <pre><code>ValueError: The two structures don't have the same number of elements.
  First structure: Tensor("backward/Tile:0", shape=(100, 50), dtype=float32), 
  second structure: 
    (&lt;tf.Tensor 'backward/bwd_states/while/GRUCell/add:0' shape=(100, 50) dtype=float32&gt;, 
     &lt;tf.Tensor 'backward/bwd_states/while/GRUCell/add:0' shape=(100, 50) dtype=float32&gt;).
  </code></pre>
  
  <p>Any clue how to resolve this?</p>