Python tensorflow.constant() Examples

The following are 30 code examples of tensorflow.constant(). You can vote up the ones you like or vote down the ones you don't like, and go to the original project or source file by following the links above each example. You may also want to check out all available functions/classes of the module tensorflow , or try the search function

Example #1

Source File: optimization_test.py From BERT-Classification-Tutorial with Apache License 2.0

6 votes

def test_adam(self):
        with self.test_session() as sess:
            w = tf.get_variable(
                "w",
                shape=[3],
                initializer=tf.constant_initializer([0.1, -0.2, -0.1]))
            x = tf.constant([0.4, 0.2, -0.5])
            loss = tf.reduce_mean(tf.square(x - w))
            tvars = tf.trainable_variables()
            grads = tf.gradients(loss, tvars)
            global_step = tf.train.get_or_create_global_step()
            optimizer = optimization.AdamWeightDecayOptimizer(learning_rate=0.2)
            train_op = optimizer.apply_gradients(zip(grads, tvars), global_step)
            init_op = tf.group(tf.global_variables_initializer(),
                               tf.local_variables_initializer())
            sess.run(init_op)
            for _ in range(100):
                sess.run(train_op)
            w_np = sess.run(w)
            self.assertAllClose(w_np.flat, [0.4, 0.2, -0.5], rtol=1e-2, atol=1e-2)

Example #2

Source File: preview.py From cwavegan with MIT License

6 votes

def noise_input_fn(params):
    """Input function for generating samples for PREDICT mode.

  Generates a single Tensor of fixed random noise. Use tf.data.Dataset to
  signal to the estimator when to terminate the generator returned by
  predict().

  Args:
    params: param `dict` passed by TPUEstimator.

  Returns:
    1-element `dict` containing the randomly generated noise.
  """

    # random noise
    np.random.seed(0)
    noise_dataset = tf.data.Dataset.from_tensors(tf.constant(
        np.random.randn(params['batch_size'], FLAGS.noise_dim), dtype=tf.float32))
    noise = noise_dataset.make_one_shot_iterator().get_next()
    return {'random_noise': noise}, None

Example #3

Source File: face_attack.py From Adversarial-Face-Attack with GNU General Public License v3.0

6 votes

def structure(self, input_tensor):
        """
        Args:
            input_tensor: NHWC
        """
        rnd = tf.random_uniform((), 135, 160, dtype=tf.int32)
        rescaled = tf.image.resize_images(
            input_tensor, [rnd, rnd], method=tf.image.ResizeMethod.NEAREST_NEIGHBOR)
        h_rem = 160 - rnd
        w_rem = 160 - rnd
        pad_left = tf.random_uniform((), 0, w_rem, dtype=tf.int32)
        pad_right = w_rem - pad_left
        pad_top = tf.random_uniform((), 0, h_rem, dtype=tf.int32)
        pad_bottom = h_rem - pad_top
        padded = tf.pad(rescaled, [[0, 0], [pad_top, pad_bottom], [
                        pad_left, pad_right], [0, 0]])
        padded.set_shape((input_tensor.shape[0], 160, 160, 3))
        output = tf.cond(tf.random_uniform(shape=[1])[0] < tf.constant(0.9),
                         lambda: padded, lambda: input_tensor)
        return output

Example #4

Source File: face_attack.py From Adversarial-Face-Attack with GNU General Public License v3.0

6 votes

def build_pgd_attack(self, eps):
        victim_embeddings = tf.constant(self.victim_embeddings, dtype=tf.float32)

        def one_step_attack(image, grad):
            """
            core components of this attack are:
            (a) PGD adversarial attack (https://arxiv.org/pdf/1706.06083.pdf)
            (b) momentum (https://arxiv.org/pdf/1710.06081.pdf)
            (c) input diversity (https://arxiv.org/pdf/1803.06978.pdf)
            """
            orig_image = image
            image = self.structure(image)
            image = (image - 127.5) / 128.0
            image = image + tf.random_uniform(tf.shape(image), minval=-1e-2, maxval=1e-2)
            prelogits, _ = self.network.inference(image, 1.0, False, bottleneck_layer_size=512)
            embeddings = tf.nn.l2_normalize(prelogits, 1, 1e-10, name='embeddings')

            embeddings = tf.reshape(embeddings[0], [512, 1])
            objective = tf.reduce_mean(tf.matmul(victim_embeddings, embeddings))  # to be maximized

            noise, = tf.gradients(objective, orig_image)

            noise = noise / tf.reduce_mean(tf.abs(noise), [1, 2, 3], keep_dims=True)
            noise = 0.9 * grad + noise

            adv = tf.clip_by_value(orig_image + tf.sign(noise) * 1.0, lower_bound, upper_bound)
            return adv, noise

        input = tf.to_float(self.image_batch)
        lower_bound = tf.clip_by_value(input - eps, 0, 255.)
        upper_bound = tf.clip_by_value(input + eps, 0, 255.)

        with tf.variable_scope(tf.get_variable_scope(), reuse=tf.AUTO_REUSE):
            adv, _ = tf.while_loop(
                lambda _, __: True, one_step_attack,
                (input, tf.zeros_like(input)),
                back_prop=False,
                maximum_iterations=100,
                parallel_iterations=1)
        self.adv_image = adv
        return adv

Example #5

Source File: test_utils_tf.py From neural-fingerprinting with BSD 3-Clause "New" or "Revised" License

6 votes

def test_clip_eta_goldilocks(self):
        # Test that the clipping handles perturbations that are
        # too small, just right, and too big correctly
        eta = tf.constant([[2.], [3.], [4.]])
        assert eta.dtype == tf.float32, eta.dtype
        eps = 3.
        for ord_arg in [np.inf, 1, 2]:
            for sign in [-1., 1.]:
                clipped = clip_eta(eta * sign, ord_arg, eps)
                clipped_value = self.sess.run(clipped)
                gold = sign * np.array([[2.], [3.], [3.]])
                self.assertClose(clipped_value, gold)
                grad, = tf.gradients(clipped, eta)
                grad_value = self.sess.run(grad)
                # Note: the second 1. is debatable (the left-sided derivative
                # and the right-sided derivative do not match, so formally
                # the derivative is not defined). This test makes sure that
                # we at least handle this oddity consistently across all the
                # argument values we test
                gold = sign * np.array([[1.], [1.], [0.]])
                assert np.allclose(grad_value, gold)

Example #6

Source File: test_dropout.py From neural-fingerprinting with BSD 3-Clause "New" or "Revised" License

6 votes

def test_drop():
    # Make sure dropout is activated successfully

    # We would like to configure the test to deterministically drop,
    # so that the test does not need to use multiple runs.
    # However, tf.nn.dropout divides by include_prob, so zero or
    # infinitesimal include_prob causes NaNs.
    # 1e-8 does not cause NaNs and shouldn't be a significant source
    # of test flakiness relative to dependency downloads failing, etc.
    model = MLP(input_shape=[1, 1], layers=[Dropout(name='output',
                                                    include_prob=1e-8)])
    x = tf.constant([[1]], dtype=tf.float32)
    y = model.get_layer(x, 'output', dropout=True)
    sess = tf.Session()
    y_value = sess.run(y)
    # Subject to very rare random failure because include_prob is not exact 0
    assert y_value == 0., y_value

Example #7

Source File: tensor.py From spleeter with MIT License

6 votes

def check_tensor_shape(tensor_tf, target_shape):
    """ Return a Tensorflow boolean graph that indicates whether
    sample[features_key] has the specified target shape. Only check
    not None entries of target_shape.

    :param tensor_tf: Tensor to check shape for.
    :param target_shape: Target shape to compare tensor to.
    :returns: True if shape is valid, False otherwise (as TF boolean).
    """
    result = tf.constant(True)
    for i, target_length in enumerate(target_shape):
        if target_length:
            result = tf.logical_and(
                result,
                tf.equal(tf.constant(target_length), tf.shape(tensor_tf)[i]))
    return result

Example #8