Unbroadcast batch size dimension in Theano backend (keras-team#7957)

* Unbroadcast batch size dimension in Theano backend Unbroadcasting batch size dimension is important when batch size is 1 * rnn unit test batch size of 1
sauerburger · Sep 22, 2017 · 710898f · 710898f
1 parent 2dfba02
commit 710898f
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diff --git a/keras/backend/theano_backend.py b/keras/backend/theano_backend.py
@@ -1412,7 +1412,7 @@ def _step(inputs, *states):
             # Theano likes to make shape==1 dimensions
             # in the initial states (outputs_info) broadcastable
             if len(initial_states) > 0:
-                initial_states[0] = T.unbroadcast(initial_states[0], 1)
+                initial_states[0] = T.unbroadcast(initial_states[0], 0, 1)
 
             results, _ = theano.scan(
                 _step,

diff --git a/tests/keras/layers/recurrent_test.py b/tests/keras/layers/recurrent_test.py
@@ -552,5 +552,17 @@ def test_stacked_rnn_attributes():
     assert layer.get_losses_for(x) == [y]
 
 
+@rnn_test
+def test_batch_size_equal_one(layer_class):
+    inputs = Input(batch_shape=(1, timesteps, embedding_dim))
+    layer = layer_class(units)
+    outputs = layer(inputs)
+    model = Model(inputs, outputs)
+    model.compile('sgd', 'mse')
+    x = np.random.random((1, timesteps, embedding_dim))
+    y = np.random.random((1, units))
+    model.train_on_batch(x, y)
+
+
 if __name__ == '__main__':
     pytest.main([__file__])