tensorflow_probability/examples/latent_dirichlet_allocation_distributions.py
def make_encoder(activation, num_topics, layer_sizes):
  """Create the encoder function.

  Args:
    activation: Activation function to use.
    num_topics: The number of topics.
    layer_sizes: The number of hidden units per layer in the encoder.

  Returns:
    encoder: A `callable` mapping a bag-of-words `Tensor` to a
      `tfd.Distribution` instance over topics.
  """
  encoder_net = tf.keras.Sequential()
  for num_hidden_units in layer_sizes:
    encoder_net.add(
        tf.keras.layers.Dense(
            num_hidden_units,
            activation=activation,
            kernel_initializer=tf.compat.v1.glorot_normal_initializer()))
  encoder_net.add(
      tf.keras.layers.Dense(
          num_topics,
          activation=tf.nn.softplus,
          kernel_initializer=tf.compat.v1.glorot_normal_initializer()))

  def encoder(bag_of_words):
    net = _clip_dirichlet_parameters(encoder_net(bag_of_words))
    return tfd.Dirichlet(concentration=net,
                         name="topics_posterior")

  return encoder
def make_encoder(activation, num_topics, layer_sizes):
  """Create the encoder function.

  Args:
    activation: Activation function to use.
    num_topics: The number of topics.
    layer_sizes: The number of hidden units per layer in the encoder.

  Returns:
    encoder: A `callable` mapping a bag-of-words `Tensor` to a
      `tfd.Distribution` instance over topics.
  """
  encoder_net = tf.keras.Sequential()
  for num_hidden_units in layer_sizes:
    encoder_net.add(
        tf.keras.layers.Dense(
            num_hidden_units,
            activation=activation,
            kernel_initializer=tf.compat.v1.glorot_normal_initializer()))
  encoder_net.add(
      tf.keras.layers.Dense(
          num_topics,
          activation=tf.nn.softplus,
          kernel_initializer=tf.compat.v1.glorot_normal_initializer()))

  def encoder(bag_of_words):
    net = _clip_dirichlet_parameters(encoder_net(bag_of_words))
    return tfd.Dirichlet(concentration=net,
                         name="topics_posterior")

  return encoder
Create the encoder function.

  Args:
    activation: Activation function to use.
    num_topics: The number of topics.
    layer_sizes: The number of hidden units per layer in the encoder.

  Returns:
    encoder: A `callable` mapping a bag-of-words `Tensor` to a
      `tfd.Distribution` instance over topics.