Python keras.engine.topology.Input() Examples

def test_specify_initial_state_keras_tensor(layer_class):
    num_states = 2 if layer_class is recurrent.LSTM else 1

    # Test with Keras tensor
    inputs = Input((timesteps, embedding_dim))
    initial_state = [Input((units,)) for _ in range(num_states)]
    layer = layer_class(units)
    if len(initial_state) == 1:
        output = layer(inputs, initial_state=initial_state[0])
    else:
        output = layer(inputs, initial_state=initial_state)
    assert initial_state[0] in layer._inbound_nodes[0].input_tensors

    model = Model([inputs] + initial_state, output)
    model.compile(loss='categorical_crossentropy', optimizer='adam')

    inputs = np.random.random((num_samples, timesteps, embedding_dim))
    initial_state = [np.random.random((num_samples, units))
                     for _ in range(num_states)]
    targets = np.random.random((num_samples, units))
    model.fit([inputs] + initial_state, targets) 

def test_specify_state_with_masking(layer_class):
    ''' This test based on a previously failing issue here:
    https://github.com/keras-team/keras/issues/1567
    '''
    num_states = 2 if layer_class is recurrent.LSTM else 1

    inputs = Input((timesteps, embedding_dim))
    _ = Masking()(inputs)
    initial_state = [Input((units,)) for _ in range(num_states)]
    output = layer_class(units)(inputs, initial_state=initial_state)

    model = Model([inputs] + initial_state, output)
    model.compile(loss='categorical_crossentropy', optimizer='adam')

    inputs = np.random.random((num_samples, timesteps, embedding_dim))
    initial_state = [np.random.random((num_samples, units))
                     for _ in range(num_states)]
    targets = np.random.random((num_samples, units))
    model.fit([inputs] + initial_state, targets) 

def test_stacked_rnn_attributes():
    cells = [recurrent.LSTMCell(3),
             recurrent.LSTMCell(3, kernel_regularizer='l2')]
    layer = recurrent.RNN(cells)
    layer.build((None, None, 5))

    # Test regularization losses
    assert len(layer.losses) == 1

    # Test weights
    assert len(layer.trainable_weights) == 6
    cells[0].trainable = False
    assert len(layer.trainable_weights) == 3
    assert len(layer.non_trainable_weights) == 3

    # Test `get_losses_for`
    x = keras.Input((None, 5))
    y = K.sum(x)
    cells[0].add_loss(y, inputs=x)
    assert layer.get_losses_for(x) == [y] 

def test_stacked_rnn_attributes():
    cells = [recurrent.LSTMCell(3),
             recurrent.LSTMCell(3, kernel_regularizer='l2')]
    layer = recurrent.RNN(cells)
    layer.build((None, None, 5))

    # Test regularization losses
    assert len(layer.losses) == 1

    # Test weights
    assert len(layer.trainable_weights) == 6
    cells[0].trainable = False
    assert len(layer.trainable_weights) == 3
    assert len(layer.non_trainable_weights) == 3

    # Test `get_losses_for`
    x = keras.Input((None, 5))
    y = K.sum(x)
    cells[0].add_loss(y, inputs=x)
    assert layer.get_losses_for(x) == [y] 

def test_specify_initial_state_keras_tensor(layer_class):
    num_states = 2 if layer_class is recurrent.LSTM else 1

    # Test with Keras tensor
    inputs = Input((timesteps, embedding_dim))
    initial_state = [Input((units,)) for _ in range(num_states)]
    layer = layer_class(units)
    if len(initial_state) == 1:
        output = layer(inputs, initial_state=initial_state[0])
    else:
        output = layer(inputs, initial_state=initial_state)
    assert initial_state[0] in layer._inbound_nodes[0].input_tensors

    model = Model([inputs] + initial_state, output)
    model.compile(loss='categorical_crossentropy', optimizer='adam')

    inputs = np.random.random((num_samples, timesteps, embedding_dim))
    initial_state = [np.random.random((num_samples, units))
                     for _ in range(num_states)]
    targets = np.random.random((num_samples, units))
    model.fit([inputs] + initial_state, targets) 

def test_specify_initial_state_non_keras_tensor(layer_class):
    num_states = 2 if layer_class is recurrent.LSTM else 1

    # Test with non-Keras tensor
    inputs = Input((timesteps, embedding_dim))
    initial_state = [K.random_normal_variable((num_samples, units), 0, 1)
                     for _ in range(num_states)]
    layer = layer_class(units)
    output = layer(inputs, initial_state=initial_state)

    model = Model(inputs, output)
    model.compile(loss='categorical_crossentropy', optimizer='adam')

    inputs = np.random.random((num_samples, timesteps, embedding_dim))
    targets = np.random.random((num_samples, units))
    model.fit(inputs, targets) 

def test_initial_states_as_other_inputs(layer_class):
    num_states = 2 if layer_class is recurrent.LSTM else 1

    # Test with Keras tensor
    main_inputs = Input((timesteps, embedding_dim))
    initial_state = [Input((units,)) for _ in range(num_states)]
    inputs = [main_inputs] + initial_state

    layer = layer_class(units)
    output = layer(inputs)
    assert initial_state[0] in layer._inbound_nodes[0].input_tensors

    model = Model(inputs, output)
    model.compile(loss='categorical_crossentropy', optimizer='adam')

    main_inputs = np.random.random((num_samples, timesteps, embedding_dim))
    initial_state = [np.random.random((num_samples, units))
                     for _ in range(num_states)]
    targets = np.random.random((num_samples, units))
    model.train_on_batch([main_inputs] + initial_state, targets) 

def test_specify_state_with_masking(layer_class):
    ''' This test based on a previously failing issue here:
    https://github.com/keras-team/keras/issues/1567
    '''
    num_states = 2 if layer_class is recurrent.LSTM else 1

    inputs = Input((timesteps, embedding_dim))
    _ = Masking()(inputs)
    initial_state = [Input((units,)) for _ in range(num_states)]
    output = layer_class(units)(inputs, initial_state=initial_state)

    model = Model([inputs] + initial_state, output)
    model.compile(loss='categorical_crossentropy', optimizer='adam')

    inputs = np.random.random((num_samples, timesteps, embedding_dim))
    initial_state = [np.random.random((num_samples, units))
                     for _ in range(num_states)]
    targets = np.random.random((num_samples, units))
    model.fit([inputs] + initial_state, targets) 

def test_trainable_argument():
    x = np.random.random((5, 3))
    y = np.random.random((5, 2))

    model = Sequential()
    model.add(Dense(2, input_dim=3, trainable=False))
    model.compile('rmsprop', 'mse')
    out = model.predict(x)
    model.train_on_batch(x, y)
    out_2 = model.predict(x)
    assert_allclose(out, out_2)

    # test with nesting
    inputs = Input(shape=(3,))
    outputs = model(inputs)
    model = Model(inputs, outputs)
    model.compile('rmsprop', 'mse')
    out = model.predict(x)
    model.train_on_batch(x, y)
    out_2 = model.predict(x)
    assert_allclose(out, out_2) 

def test_initial_states_as_other_inputs(layer_class):
    num_states = 2 if layer_class is recurrent.LSTM else 1

    # Test with Keras tensor
    main_inputs = Input((timesteps, embedding_dim))
    initial_state = [Input((units,)) for _ in range(num_states)]
    inputs = [main_inputs] + initial_state

    layer = layer_class(units)
    output = layer(inputs)
    assert initial_state[0] in layer._inbound_nodes[0].input_tensors

    model = Model(inputs, output)
    model.compile(loss='categorical_crossentropy', optimizer='adam')

    main_inputs = np.random.random((num_samples, timesteps, embedding_dim))
    initial_state = [np.random.random((num_samples, units))
                     for _ in range(num_states)]
    targets = np.random.random((num_samples, units))
    model.train_on_batch([main_inputs] + initial_state, targets) 

def test_specify_state_with_masking(layer_class):
    ''' This test based on a previously failing issue here:
    https://github.com/keras-team/keras/issues/1567
    '''
    num_states = 2 if layer_class is recurrent.LSTM else 1

    inputs = Input((timesteps, embedding_dim))
    _ = Masking()(inputs)
    initial_state = [Input((units,)) for _ in range(num_states)]
    output = layer_class(units)(inputs, initial_state=initial_state)

    model = Model([inputs] + initial_state, output)
    model.compile(loss='categorical_crossentropy', optimizer='adam')

    inputs = np.random.random((num_samples, timesteps, embedding_dim))
    initial_state = [np.random.random((num_samples, units))
                     for _ in range(num_states)]
    targets = np.random.random((num_samples, units))
    model.fit([inputs] + initial_state, targets) 

def test_specify_initial_state_non_keras_tensor(layer_class):
    num_states = 2 if layer_class is recurrent.LSTM else 1

    # Test with non-Keras tensor
    inputs = Input((timesteps, embedding_dim))
    initial_state = [K.random_normal_variable((num_samples, units), 0, 1)
                     for _ in range(num_states)]
    layer = layer_class(units)
    output = layer(inputs, initial_state=initial_state)

    model = Model(inputs, output)
    model.compile(loss='categorical_crossentropy', optimizer='adam')

    inputs = np.random.random((num_samples, timesteps, embedding_dim))
    targets = np.random.random((num_samples, units))
    model.fit(inputs, targets) 

def test_specify_initial_state_keras_tensor(layer_class):
    num_states = 2 if layer_class is recurrent.LSTM else 1

    # Test with Keras tensor
    inputs = Input((timesteps, embedding_dim))
    initial_state = [Input((units,)) for _ in range(num_states)]
    layer = layer_class(units)
    if len(initial_state) == 1:
        output = layer(inputs, initial_state=initial_state[0])
    else:
        output = layer(inputs, initial_state=initial_state)
    assert initial_state[0] in layer._inbound_nodes[0].input_tensors

    model = Model([inputs] + initial_state, output)
    model.compile(loss='categorical_crossentropy', optimizer='adam')

    inputs = np.random.random((num_samples, timesteps, embedding_dim))
    initial_state = [np.random.random((num_samples, units))
                     for _ in range(num_states)]
    targets = np.random.random((num_samples, units))
    model.fit([inputs] + initial_state, targets) 

def test_specify_initial_state_non_keras_tensor(layer_class):
    num_states = 2 if layer_class is recurrent.LSTM else 1

    # Test with non-Keras tensor
    inputs = Input((timesteps, embedding_dim))
    initial_state = [K.random_normal_variable((num_samples, units), 0, 1)
                     for _ in range(num_states)]
    layer = layer_class(units)
    output = layer(inputs, initial_state=initial_state)

    model = Model(inputs, output)
    model.compile(loss='categorical_crossentropy', optimizer='adam')

    inputs = np.random.random((num_samples, timesteps, embedding_dim))
    targets = np.random.random((num_samples, units))
    model.fit(inputs, targets) 

def test_specify_state_with_masking(layer_class):
    ''' This test based on a previously failing issue here:
    https://github.com/keras-team/keras/issues/1567
    '''
    num_states = 2 if layer_class is recurrent.LSTM else 1

    inputs = Input((timesteps, embedding_dim))
    _ = Masking()(inputs)
    initial_state = [Input((units,)) for _ in range(num_states)]
    output = layer_class(units)(inputs, initial_state=initial_state)

    model = Model([inputs] + initial_state, output)
    model.compile(loss='categorical_crossentropy', optimizer='adam')

    inputs = np.random.random((num_samples, timesteps, embedding_dim))
    initial_state = [np.random.random((num_samples, units))
                     for _ in range(num_states)]
    targets = np.random.random((num_samples, units))
    model.fit([inputs] + initial_state, targets) 

def test_trainable_argument():
    x = np.random.random((5, 3))
    y = np.random.random((5, 2))

    model = Sequential()
    model.add(Dense(2, input_dim=3, trainable=False))
    model.compile('rmsprop', 'mse')
    out = model.predict(x)
    model.train_on_batch(x, y)
    out_2 = model.predict(x)
    assert_allclose(out, out_2)

    # test with nesting
    inputs = Input(shape=(3,))
    outputs = model(inputs)
    model = Model(inputs, outputs)
    model.compile('rmsprop', 'mse')
    out = model.predict(x)
    model.train_on_batch(x, y)
    out_2 = model.predict(x)
    assert_allclose(out, out_2) 

def test_specify_initial_state_non_keras_tensor(layer_class):
    num_states = 2 if layer_class is recurrent.LSTM else 1

    # Test with non-Keras tensor
    inputs = Input((timesteps, embedding_dim))
    initial_state = [K.random_normal_variable((num_samples, units), 0, 1)
                     for _ in range(num_states)]
    layer = layer_class(units)
    output = layer(inputs, initial_state=initial_state)

    model = Model(inputs, output)
    model.compile(loss='categorical_crossentropy', optimizer='adam')

    inputs = np.random.random((num_samples, timesteps, embedding_dim))
    targets = np.random.random((num_samples, units))
    model.fit(inputs, targets) 

def test_trainable_argument():
    x = np.random.random((5, 3))
    y = np.random.random((5, 2))

    model = Sequential()
    model.add(Dense(2, input_dim=3, trainable=False))
    model.compile('rmsprop', 'mse')
    out = model.predict(x)
    model.train_on_batch(x, y)
    out_2 = model.predict(x)
    assert_allclose(out, out_2)

    # test with nesting
    inputs = Input(shape=(3,))
    outputs = model(inputs)
    model = Model(inputs, outputs)
    model.compile('rmsprop', 'mse')
    out = model.predict(x)
    model.train_on_batch(x, y)
    out_2 = model.predict(x)
    assert_allclose(out, out_2) 

def test_trainable_argument():
    x = np.random.random((5, 3))
    y = np.random.random((5, 2))

    model = Sequential()
    model.add(Dense(2, input_dim=3, trainable=False))
    model.compile('rmsprop', 'mse')
    out = model.predict(x)
    model.train_on_batch(x, y)
    out_2 = model.predict(x)
    assert_allclose(out, out_2)

    # test with nesting
    inputs = Input(shape=(3,))
    outputs = model(inputs)
    model = Model(inputs, outputs)
    model.compile('rmsprop', 'mse')
    out = model.predict(x)
    model.train_on_batch(x, y)
    out_2 = model.predict(x)
    assert_allclose(out, out_2) 

def test_stacked_rnn_attributes():
    cells = [recurrent.LSTMCell(3),
             recurrent.LSTMCell(3, kernel_regularizer='l2')]
    layer = recurrent.RNN(cells)
    layer.build((None, None, 5))

    # Test regularization losses
    assert len(layer.losses) == 1

    # Test weights
    assert len(layer.trainable_weights) == 6
    cells[0].trainable = False
    assert len(layer.trainable_weights) == 3
    assert len(layer.non_trainable_weights) == 3

    # Test `get_losses_for`
    x = keras.Input((None, 5))
    y = K.sum(x)
    cells[0].add_loss(y, inputs=x)
    assert layer.get_losses_for(x) == [y] 

def test_stacked_rnn_attributes():
    cells = [recurrent.LSTMCell(3),
             recurrent.LSTMCell(3, kernel_regularizer='l2')]
    layer = recurrent.RNN(cells)
    layer.build((None, None, 5))

    # Test regularization losses
    assert len(layer.losses) == 1

    # Test weights
    assert len(layer.trainable_weights) == 6
    cells[0].trainable = False
    assert len(layer.trainable_weights) == 3
    assert len(layer.non_trainable_weights) == 3

    # Test `get_losses_for`
    x = keras.Input((None, 5))
    y = K.sum(x)
    cells[0].add_loss(y, inputs=x)
    assert layer.get_losses_for(x) == [y] 

def test_state_reuse_with_dropout(layer_class):
    input1 = Input(batch_shape=(num_samples, timesteps, embedding_dim))
    layer = layer_class(units, return_state=True, return_sequences=True, dropout=0.2)
    state = layer(input1)[1:]

    input2 = Input(batch_shape=(num_samples, timesteps, embedding_dim))
    output = layer_class(units)(input2, initial_state=state)
    model = Model([input1, input2], output)

    inputs = [np.random.random((num_samples, timesteps, embedding_dim)),
              np.random.random((num_samples, timesteps, embedding_dim))]
    outputs = model.predict(inputs) 

def test_state_reuse(layer_class):
    inputs = Input(batch_shape=(num_samples, timesteps, embedding_dim))
    layer = layer_class(units, return_state=True, return_sequences=True)
    outputs = layer(inputs)
    output, state = outputs[0], outputs[1:]
    output = layer_class(units)(output, initial_state=state)
    model = Model(inputs, output)

    inputs = np.random.random((num_samples, timesteps, embedding_dim))
    outputs = model.predict(inputs) 

def test_state_reuse(layer_class):
    inputs = Input(batch_shape=(num_samples, timesteps, embedding_dim))
    layer = layer_class(units, return_state=True, return_sequences=True)
    outputs = layer(inputs)
    output, state = outputs[0], outputs[1:]
    output = layer_class(units)(output, initial_state=state)
    model = Model(inputs, output)

    inputs = np.random.random((num_samples, timesteps, embedding_dim))
    outputs = model.predict(inputs) 

def test_weighted_masked_objective():
    a = Input(shape=(3,), name='input_a')

    # weighted_masked_objective
    def mask_dummy(y_true=None, y_pred=None, weight=None):
        return K.placeholder(y_true.shape)

    weighted_function = _weighted_masked_objective(losses.categorical_crossentropy)
    weighted_function(a, a, None) 

def test_return_state(layer_class):
    num_states = 2 if layer_class is recurrent.LSTM else 1

    inputs = Input(batch_shape=(num_samples, timesteps, embedding_dim))
    layer = layer_class(units, return_state=True, stateful=True)
    outputs = layer(inputs)
    output, state = outputs[0], outputs[1:]
    assert len(state) == num_states
    model = Model(inputs, state[0])

    inputs = np.random.random((num_samples, timesteps, embedding_dim))
    state = model.predict(inputs)
    np.testing.assert_allclose(K.eval(layer.states[0]), state, atol=1e-4) 

def test_trainable_weights_count_consistency():
    """Tests the trainable weights consistency check of Model.

    This verifies that a warning is shown if model.trainable is modified
    and the model is summarized/run without a new call to .compile()

    Reproduce issue #8121
    """
    a = Input(shape=(3,), name='input_a')
    model1 = Model(inputs=a, outputs=Dense(1)(a))

    model1.trainable = False
    b = Input(shape=(3,), name='input_b')
    y = model1(b)
    model2 = Model(inputs=b, outputs=Dense(1)(y))

    model2.compile(optimizer='adam', loss='mse')

    model1.trainable = True

    # Should warn on .summary()
    with pytest.warns(UserWarning) as w:
        model2.summary()
    warning_raised = any(['Discrepancy' in str(w_.message) for w_ in w])
    assert warning_raised, 'No warning raised when trainable is modified without .compile.'

    # And on .fit()
    with pytest.warns(UserWarning) as w:
        model2.fit(x=np.zeros((5, 3)), y=np.zeros((5, 1)))
    warning_raised = any(['Discrepancy' in str(w_.message) for w_ in w])
    assert warning_raised, 'No warning raised when trainable is modified without .compile.'

    # And shouldn't warn if we recompile
    model2.compile(optimizer='adam', loss='mse')
    with pytest.warns(None) as w:
        model2.summary()
    assert len(w) == 0, "Warning raised even when .compile() is called after modifying .trainable" 

def test_model_with_partial_loss():
    a = Input(shape=(3,), name='input_a')
    a_2 = Dense(4, name='dense_1')(a)
    dp = Dropout(0.5, name='dropout')
    a_3 = dp(a_2)
    model = Model(a, [a_2, a_3])

    optimizer = 'rmsprop'
    loss = {'dropout': 'mse'}
    model.compile(optimizer, loss, metrics=['mae'])

    input_a_np = np.random.random((10, 3))
    output_a_np = np.random.random((10, 4))

    # test train_on_batch
    out = model.train_on_batch(input_a_np, output_a_np)
    out = model.test_on_batch(input_a_np, output_a_np)
    # fit
    out = model.fit(input_a_np, [output_a_np])
    # evaluate
    out = model.evaluate(input_a_np, [output_a_np])

    # Same without dropout.
    a = Input(shape=(3,), name='input_a')
    a_2 = Dense(4, name='dense_1')(a)
    a_3 = Dense(4, name='dense_2')(a_2)
    model = Model(a, [a_2, a_3])

    optimizer = 'rmsprop'
    loss = {'dense_2': 'mse'}
    model.compile(optimizer, loss, metrics={'dense_1': 'mae'})

    # test train_on_batch
    out = model.train_on_batch(input_a_np, output_a_np)
    out = model.test_on_batch(input_a_np, output_a_np)
    # fit
    out = model.fit(input_a_np, [output_a_np])
    # evaluate
    out = model.evaluate(input_a_np, [output_a_np]) 

def test_sparse_inputs_targets():
    test_inputs = [sparse.random(6, 3, density=0.25).tocsr() for _ in range(2)]
    test_outputs = [sparse.random(6, i, density=0.25).tocsr() for i in range(3, 5)]
    in1 = Input(shape=(3,))
    in2 = Input(shape=(3,))
    out1 = Dropout(0.5, name='dropout')(in1)
    out2 = Dense(4, name='dense_1')(in2)
    model = Model([in1, in2], [out1, out2])
    model.predict(test_inputs, batch_size=2)
    model.compile('rmsprop', 'mse')
    model.fit(test_inputs, test_outputs, epochs=1, batch_size=2, validation_split=0.5)
    model.evaluate(test_inputs, test_outputs, batch_size=2) 

def test_warnings():
    a = Input(shape=(3,), name='input_a')
    b = Input(shape=(3,), name='input_b')

    a_2 = Dense(4, name='dense_1')(a)
    dp = Dropout(0.5, name='dropout')
    b_2 = dp(b)

    model = Model([a, b], [a_2, b_2])

    optimizer = 'rmsprop'
    loss = 'mse'
    loss_weights = [1., 0.5]
    model.compile(optimizer, loss, metrics=[], loss_weights=loss_weights,
                  sample_weight_mode=None)

    def gen_data(batch_sz):
        while True:
            yield ([np.random.random((batch_sz, 3)), np.random.random((batch_sz, 3))],
                   [np.random.random((batch_sz, 4)), np.random.random((batch_sz, 3))])

    with pytest.warns(Warning) as w:
        out = model.fit_generator(gen_data(4), steps_per_epoch=10, use_multiprocessing=True, workers=2)
    warning_raised = any(['Sequence' in str(w_.message) for w_ in w])
    assert warning_raised, 'No warning raised when using generator with processes.'

    with pytest.warns(None) as w:
        out = model.fit_generator(RandomSequence(3), steps_per_epoch=4, use_multiprocessing=True, workers=2)
    assert all(['Sequence' not in str(w_.message) for w_ in w]), 'A warning was raised for Sequence.'