Python feature_column.input_layer函数代码示例

  def testWarmStartInputLayerEmbeddingColumn(self):
    # Create old and new vocabs for embedding column "sc_vocab".
    prev_vocab_path = self._write_vocab(["apple", "banana", "guava", "orange"],
                                        "old_vocab")
    new_vocab_path = self._write_vocab(
        ["orange", "guava", "banana", "apple", "raspberry", "blueberry"],
        "new_vocab")

    # Save checkpoint from which to warm-start.
    with ops.Graph().as_default() as g:
      with self.test_session(graph=g) as sess:
        _ = variable_scope.get_variable(
            "input_layer/sc_vocab_embedding/embedding_weights",
            initializer=[[0.5, 0.4], [1., 1.1], [2., 2.2], [3., 3.3]])
        self._write_checkpoint(sess)

    def _partitioner(shape, dtype):  # pylint:disable=unused-argument
      # Partition each var into 2 equal slices.
      partitions = [1] * len(shape)
      partitions[0] = min(2, shape[0].value)
      return partitions

    # Create feature columns.
    sc_vocab = fc.categorical_column_with_vocabulary_file(
        "sc_vocab", vocabulary_file=new_vocab_path, vocabulary_size=6)
    emb_vocab = fc.embedding_column(
        categorical_column=sc_vocab,
        dimension=2,
        # Can't use constant_initializer with load_and_remap.  In practice,
        # use a truncated normal initializer.
        initializer=init_ops.random_uniform_initializer(
            minval=0.42, maxval=0.42))
    all_deep_cols = [emb_vocab]
    # New graph, new session with warmstarting.
    with ops.Graph().as_default() as g:
      with self.test_session(graph=g) as sess:
        cols_to_vars = {}
        with variable_scope.variable_scope("", partitioner=_partitioner):
          # Create the variables.
          fc.input_layer(
              features=self._create_dummy_inputs(),
              feature_columns=all_deep_cols,
              cols_to_vars=cols_to_vars)
        ws_settings = ws_util._WarmStartSettings(
            self.get_temp_dir(), col_to_prev_vocab={
                emb_vocab: prev_vocab_path
            })
        ws_util._warmstart_input_layer(cols_to_vars, ws_settings)
        sess.run(variables.global_variables_initializer())
        # Verify weights were correctly warmstarted. Var corresponding to
        # emb_vocab should be correctly warmstarted after vocab remapping.
        # Missing values are filled in with the EmbeddingColumn's initializer.
        self._assert_cols_to_vars(
            cols_to_vars, {
                emb_vocab: [
                    np.array([[3., 3.3], [2., 2.2], [1., 1.1]]),
                    np.array([[0.5, 0.4], [0.42, 0.42], [0.42, 0.42]])
                ]
            }, sess)

def _parse_features_if_necessary(features, feature_columns):
  """Helper function to convert the input points into a usable format.

  Args:
    features: The input features.
    feature_columns: An optionable iterable containing all the feature columns
      used by the model. All items in the set should be feature column instances
      that can be passed to `tf.feature_column.input_layer`. If this is None,
      all features will be used.

  Returns:
    If `features` is a dict of `k` features (optionally filtered by
    `feature_columns`), each of which is a vector of `n` scalars, the return
    value is a Tensor of shape `(n, k)` representing `n` input points, where the
    items in the `k` dimension are sorted lexicographically by `features` key.
    If `features` is not a dict, it is returned unmodified.
  """
  if not isinstance(features, dict):
    return features

  if feature_columns:
    return fc.input_layer(features, feature_columns)

  keys = sorted(features.keys())
  with ops.colocate_with(features[keys[0]]):
    return array_ops.concat([features[k] for k in keys], axis=1)

  def test_sequence_example_into_input_layer(self):
    examples = [_make_sequence_example().SerializeToString()] * 100
    ctx_cols, seq_cols = self._build_feature_columns()

    def _parse_example(example):
      ctx, seq = parsing_ops.parse_single_sequence_example(
          example,
          context_features=fc.make_parse_example_spec(ctx_cols),
          sequence_features=fc.make_parse_example_spec(seq_cols))
      ctx.update(seq)
      return ctx

    ds = dataset_ops.Dataset.from_tensor_slices(examples)
    ds = ds.map(_parse_example)
    ds = ds.batch(20)

    # Test on a single batch
    features = ds.make_one_shot_iterator().get_next()

    # Tile the context features across the sequence features
    seq_layer, _ = sfc.sequence_input_layer(features, seq_cols)
    ctx_layer = fc.input_layer(features, ctx_cols)
    input_layer = sfc.concatenate_context_input(ctx_layer, seq_layer)

    rnn_layer = recurrent.RNN(recurrent.SimpleRNNCell(10))
    output = rnn_layer(input_layer)

    with self.cached_session() as sess:
      sess.run(variables.global_variables_initializer())
      features_r = sess.run(features)
      self.assertAllEqual(features_r['int_list'].dense_shape, [20, 3, 6])

      output_r = sess.run(output)
      self.assertAllEqual(output_r.shape, [20, 10])

  def dnn_logit_fn(features, mode):
    """Deep Neural Network logit_fn.

    Args:
      features: This is the first item returned from the `input_fn`
                passed to `train`, `evaluate`, and `predict`. This should be a
                single `Tensor` or `dict` of same.
      mode: Optional. Specifies if this training, evaluation or prediction. See
            `ModeKeys`.

    Returns:
      A `Tensor` representing the logits, or a list of `Tensor`'s representing
      multiple logits in the MultiHead case.
    """
    with variable_scope.variable_scope(
        'input_from_feature_columns',
        values=tuple(six.itervalues(features)),
        partitioner=input_layer_partitioner):
      net = feature_column_lib.input_layer(
          features=features, feature_columns=feature_columns)

    for layer_id, num_hidden_units in enumerate(hidden_units):
      with variable_scope.variable_scope(
          'hiddenlayer_%d' % layer_id, values=(net,)) as hidden_layer_scope:
        net = core_layers.dense(
            net,
            units=num_hidden_units,
            activation=activation_fn,
            kernel_initializer=init_ops.glorot_uniform_initializer(),
            name=hidden_layer_scope)
        if dropout is not None and mode == model_fn.ModeKeys.TRAIN:
          net = core_layers.dropout(net, rate=dropout, training=True)
      _add_hidden_layer_summary(net, hidden_layer_scope.name)

    if isinstance(units, int):
      with variable_scope.variable_scope(
          'logits', values=(net,)) as logits_scope:
        logits = core_layers.dense(
            net,
            units=units,
            activation=None,
            kernel_initializer=init_ops.glorot_uniform_initializer(),
            name=logits_scope)
      _add_hidden_layer_summary(logits, logits_scope.name)
    else:
      logits = []
      for head_index, logits_dimension in enumerate(units):
        with variable_scope.variable_scope(
            'logits_head_{}'.format(head_index), values=(net,)) as logits_scope:
          these_logits = core_layers.dense(
              net,
              units=logits_dimension,
              activation=None,
              kernel_initializer=init_ops.glorot_uniform_initializer(),
              name=logits_scope)
        _add_hidden_layer_summary(these_logits, logits_scope.name)
        logits.append(these_logits)
    return logits

  def dnn_logit_fn(features, mode):
    """Deep Neural Network logit_fn.

    Args:
      features: This is the first item returned from the `input_fn`
                passed to `train`, `evaluate`, and `predict`. This should be a
                single `Tensor` or `dict` of same.
      mode: Optional. Specifies if this training, evaluation or prediction. See
            `ModeKeys`.

    Returns:
      A `Tensor` representing the logits, or a list of `Tensor`'s representing
      multiple logits in the MultiHead case.
    """
    is_training = mode == model_fn.ModeKeys.TRAIN
    with variable_scope.variable_scope(
        'input_from_feature_columns',
        values=tuple(six.itervalues(features)),
        partitioner=input_layer_partitioner):
      net = feature_column_lib.input_layer(
          features=features, feature_columns=feature_columns)
    for layer_id, num_hidden_units in enumerate(hidden_units):
      with variable_scope.variable_scope(
          'hiddenlayer_%d' % layer_id, values=(net,)) as hidden_layer_scope:
        net = core_layers.dense(
            net,
            units=num_hidden_units,
            activation=activation_fn,
            kernel_initializer=init_ops.glorot_uniform_initializer(),
            name=hidden_layer_scope)
        if dropout is not None and is_training:
          net = core_layers.dropout(net, rate=dropout, training=True)
        if batch_norm:
          # TODO(hjm): In future, if this becomes popular, we can enable
          # customization of the batch normalization params by accepting a
          # list of `BatchNormalization` instances as `batch_norm`.
          net = normalization.batch_normalization(
              net,
              # The default momentum 0.99 actually crashes on certain
              # problem, so here we use 0.999, which is the default of
              # tf.contrib.layers.batch_norm.
              momentum=0.999,
              training=is_training,
              name='batchnorm_%d' % layer_id)
      _add_hidden_layer_summary(net, hidden_layer_scope.name)

    with variable_scope.variable_scope('logits', values=(net,)) as logits_scope:
      logits = core_layers.dense(
          net,
          units=units,
          activation=None,
          kernel_initializer=init_ops.glorot_uniform_initializer(),
          name=logits_scope)
    _add_hidden_layer_summary(logits, logits_scope.name)

    return logits

  def rnn_logit_fn(features, mode):
    """Recurrent Neural Network logit_fn.

    Args:
      features: This is the first item returned from the `input_fn`
                passed to `train`, `evaluate`, and `predict`. This should be a
                single `Tensor` or `dict` of same.
      mode: Optional. Specifies if this training, evaluation or prediction. See
            `ModeKeys`.

    Returns:
      A `Tensor` representing the logits.
    """
    with variable_scope.variable_scope(
        'sequence_input_layer',
        values=tuple(six.itervalues(features)),
        partitioner=input_layer_partitioner):
      sequence_input, sequence_length = seq_fc.sequence_input_layer(
          features=features, feature_columns=sequence_feature_columns)
      summary.histogram('sequence_length', sequence_length)

      if context_feature_columns:
        context_input = feature_column_lib.input_layer(
            features=features,
            feature_columns=context_feature_columns)
        sequence_input = seq_fc.concatenate_context_input(
            context_input, sequence_input)

    cell = rnn_cell_fn(mode)
    # Ignore output state.
    rnn_outputs, _ = rnn.dynamic_rnn(
        cell=cell,
        inputs=sequence_input,
        sequence_length=sequence_length,
        dtype=dtypes.float32,
        time_major=False)
    last_activations = _select_last_activations(rnn_outputs, sequence_length)

    with variable_scope.variable_scope('logits', values=(rnn_outputs,)):
      logits = core_layers.dense(
          last_activations,
          units=output_units,
          activation=None,
          kernel_initializer=init_ops.glorot_uniform_initializer())
    return logits

  def _get_exogenous_embedding_shape(self):
    """Computes the shape of the vector returned by _process_exogenous_features.

    Returns:
      The shape as a list. Does not include a batch dimension.
    """
    if not self._exogenous_feature_columns:
      return (0,)
    with ops.Graph().as_default():
      parsed_features = (
          feature_column.make_parse_example_spec(
              self._exogenous_feature_columns))
      placeholder_features = parsing_ops.parse_example(
          serialized=array_ops.placeholder(shape=[None], dtype=dtypes.string),
          features=parsed_features)
      embedded = feature_column.input_layer(
          features=placeholder_features,
          feature_columns=self._exogenous_feature_columns)
      return embedded.get_shape().as_list()[1:]

  def test_indicator_column(self):
    """Tests that error is raised for sequence indicator column."""
    vocabulary_size = 3
    sparse_input = sparse_tensor.SparseTensorValue(
        # example 0, ids [2]
        # example 1, ids [0, 1]
        indices=((0, 0), (1, 0), (1, 1)),
        values=(2, 0, 1),
        dense_shape=(2, 2))

    categorical_column_a = sfc.sequence_categorical_column_with_identity(
        key='aaa', num_buckets=vocabulary_size)
    indicator_column_a = fc.indicator_column(categorical_column_a)

    with self.assertRaisesRegexp(
        ValueError,
        r'In indicator_column: aaa_indicator\. categorical_column must not be '
        r'of type _SequenceCategoricalColumn\.'):
      _ = fc.input_layer(
          features={'aaa': sparse_input},
          feature_columns=[indicator_column_a])

def extract_features(features, feature_columns):
  """Extracts columns from a dictionary of features.

  Args:
    features: `dict` of `Tensor` objects.
    feature_columns: A list of feature_columns.

  Returns:
    Seven values:
      - A list of all feature column names.
      - A list of dense floats.
      - A list of sparse float feature indices.
      - A list of sparse float feature values.
      - A list of sparse float feature shapes.
      - A list of sparse int feature indices.
      - A list of sparse int feature values.
      - A list of sparse int feature shapes.
  Raises:
    ValueError: if features is not valid.
  """
  if not features:
    raise ValueError("Features dictionary must be specified.")

  # Make a shallow copy of features to ensure downstream usage
  # is unaffected by modifications in the model function.
  features = copy.copy(features)
  if feature_columns:
    scope = "gbdt"
    with variable_scope.variable_scope(scope):
      feature_columns = list(feature_columns)
      transformed_features = {}
      for fc in feature_columns:
        # pylint: disable=protected-access
        if isinstance(fc, feature_column_lib._EmbeddingColumn):
          # pylint: enable=protected-access
          transformed_features[fc.name] = fc_core.input_layer(
              features, [fc],
              weight_collections=[scope])
        else:
          result = feature_column_ops.transform_features(features, [fc])
          if len(result) > 1:
            raise ValueError("Unexpected number of output features")
          transformed_features[fc.name] = result[list(result.keys())[0]]
    features = transformed_features

  dense_float_names = []
  dense_floats = []
  sparse_float_names = []
  sparse_float_indices = []
  sparse_float_values = []
  sparse_float_shapes = []
  sparse_int_names = []
  sparse_int_indices = []
  sparse_int_values = []
  sparse_int_shapes = []
  for key in sorted(features.keys()):
    tensor = features[key]
    if isinstance(tensor, sparse_tensor.SparseTensor):
      if tensor.values.dtype == dtypes.float32:
        sparse_float_names.append(key)
        sparse_float_indices.append(tensor.indices)
        sparse_float_values.append(tensor.values)
        sparse_float_shapes.append(tensor.dense_shape)
      elif tensor.values.dtype == dtypes.int64:
        sparse_int_names.append(key)
        sparse_int_indices.append(tensor.indices)
        sparse_int_values.append(tensor.values)
        sparse_int_shapes.append(tensor.dense_shape)
      else:
        raise ValueError("Unsupported sparse feature %s with dtype %s." %
                         (tensor.indices.name, tensor.dtype))
    else:
      if tensor.dtype == dtypes.float32:
        if len(tensor.shape) > 1 and tensor.shape[1] > 1:
          unstacked = array_ops.unstack(tensor, axis=1)
          for i in xrange(len(unstacked)):
            dense_float_names.append(_FEATURE_NAME_TEMPLATE % (key, i))
            dense_floats.append(array_ops.reshape(unstacked[i], [-1, 1]))
        else:
          dense_float_names.append(key)
          dense_floats.append(tensor)
      else:
        raise ValueError("Unsupported dense feature %s with dtype %s." %
                         (tensor.name, tensor.dtype))
  # Feature columns are logically organized into incrementing slots starting
  # from dense floats, then sparse floats then sparse ints.
  fc_names = (dense_float_names + sparse_float_names + sparse_int_names)
  return (fc_names, dense_floats, sparse_float_indices, sparse_float_values,
          sparse_float_shapes, sparse_int_indices, sparse_int_values,
          sparse_int_shapes)

def _dnn_model_fn(features, labels, mode, params, config=None):
  """Deep Neural Net model_fn.

  Args:
    features: `Tensor` or dict of `Tensor` (depends on data passed to `fit`).
    labels: `Tensor` of shape [batch_size, 1] or [batch_size] labels of
      dtype `int32` or `int64` in the range `[0, n_classes)`.
    mode: Defines whether this is training, evaluation or prediction.
      See `ModeKeys`.
    params: A dict of hyperparameters.
      The following hyperparameters are expected:
      * head: A `_Head` instance.
      * hidden_units: List of hidden units per layer.
      * feature_columns: An iterable containing all the feature columns used by
          the model.
      * optimizer: string, `Optimizer` object, or callable that defines the
          optimizer to use for training. If `None`, will use the Adagrad
          optimizer with a default learning rate of 0.05.
      * activation_fn: Activation function applied to each layer. If `None`,
          will use `tf.nn.relu`.
      * dropout: When not `None`, the probability we will drop out a given
          coordinate.
      * gradient_clip_norm: A float > 0. If provided, gradients are
          clipped to their global norm with this clipping ratio.
      * embedding_lr_multipliers: Optional. A dictionary from
          `EmbeddingColumn` to a `float` multiplier. Multiplier will be used to
          multiply with learning rate for the embedding variables.
      * input_layer_min_slice_size: Optional. The min slice size of input layer
          partitions. If not provided, will use the default of 64M.
    config: `RunConfig` object to configure the runtime settings.

  Returns:
    predictions: A dict of `Tensor` objects.
    loss: A scalar containing the loss of the step.
    train_op: The op for training.
  """
  head = params["head"]
  hidden_units = params["hidden_units"]
  feature_columns = params["feature_columns"]
  optimizer = params.get("optimizer") or "Adagrad"
  activation_fn = params.get("activation_fn")
  dropout = params.get("dropout")
  gradient_clip_norm = params.get("gradient_clip_norm")
  input_layer_min_slice_size = (
      params.get("input_layer_min_slice_size") or 64 << 20)
  num_ps_replicas = config.num_ps_replicas if config else 0
  embedding_lr_multipliers = params.get("embedding_lr_multipliers", {})

  features = _get_feature_dict(features)
  parent_scope = "dnn"

  partitioner = partitioned_variables.min_max_variable_partitioner(
      max_partitions=num_ps_replicas)
  with variable_scope.variable_scope(
      parent_scope,
      values=tuple(six.itervalues(features)),
      partitioner=partitioner):
    input_layer_partitioner = (
        partitioned_variables.min_max_variable_partitioner(
            max_partitions=num_ps_replicas,
            min_slice_size=input_layer_min_slice_size))
    with variable_scope.variable_scope(
        "input_from_feature_columns",
        values=tuple(six.itervalues(features)),
        partitioner=input_layer_partitioner) as input_layer_scope:
      if all([
          isinstance(fc, feature_column._FeatureColumn)  # pylint: disable=protected-access
          for fc in feature_columns
      ]):
        net = layers.input_from_feature_columns(
            columns_to_tensors=features,
            feature_columns=feature_columns,
            weight_collections=[parent_scope],
            scope=input_layer_scope)
      else:
        net = fc_core.input_layer(
            features=features,
            feature_columns=feature_columns,
            weight_collections=[parent_scope])

    for layer_id, num_hidden_units in enumerate(hidden_units):
      with variable_scope.variable_scope(
          "hiddenlayer_%d" % layer_id,
          values=(net,)) as hidden_layer_scope:
        net = layers.fully_connected(
            net,
            num_hidden_units,
            activation_fn=activation_fn,
            variables_collections=[parent_scope],
            scope=hidden_layer_scope)
        if dropout is not None and mode == model_fn.ModeKeys.TRAIN:
          net = layers.dropout(net, keep_prob=(1.0 - dropout))
      _add_hidden_layer_summary(net, hidden_layer_scope.name)

    with variable_scope.variable_scope(
        "logits",
        values=(net,)) as logits_scope:
      logits = layers.fully_connected(
          net,
          head.logits_dimension,
#.........这里部分代码省略.........

def _dnn_tree_combined_model_fn(
    features,
    labels,
    mode,
    head,
    dnn_hidden_units,
    dnn_feature_columns,
    tree_learner_config,
    num_trees,
    tree_examples_per_layer,
    config=None,
    dnn_optimizer="Adagrad",
    dnn_activation_fn=nn.relu,
    dnn_dropout=None,
    dnn_input_layer_partitioner=None,
    dnn_input_layer_to_tree=True,
    dnn_steps_to_train=10000,
    predict_with_tree_only=False,
    tree_feature_columns=None,
    tree_center_bias=False,
    dnn_to_tree_distillation_param=None,
    use_core_versions=False,
    output_type=model.ModelBuilderOutputType.MODEL_FN_OPS):
  """DNN and GBDT combined model_fn.

  Args:
    features: `dict` of `Tensor` objects.
    labels: Labels used to train on.
    mode: Mode we are in. (TRAIN/EVAL/INFER)
    head: A `Head` instance.
    dnn_hidden_units: List of hidden units per layer.
    dnn_feature_columns: An iterable containing all the feature columns
      used by the model's DNN.
    tree_learner_config: A config for the tree learner.
    num_trees: Number of trees to grow model to after training DNN.
    tree_examples_per_layer: Number of examples to accumulate before
      growing the tree a layer. This value has a big impact on model
      quality and should be set equal to the number of examples in
      training dataset if possible. It can also be a function that computes
      the number of examples based on the depth of the layer that's
      being built.
    config: `RunConfig` of the estimator.
    dnn_optimizer: string, `Optimizer` object, or callable that defines the
      optimizer to use for training the DNN. If `None`, will use the Adagrad
      optimizer with default learning rate of 0.001.
    dnn_activation_fn: Activation function applied to each layer of the DNN.
      If `None`, will use `tf.nn.relu`.
    dnn_dropout: When not `None`, the probability to drop out a given
      unit in the DNN.
    dnn_input_layer_partitioner: Partitioner for input layer of the DNN.
      Defaults to `min_max_variable_partitioner` with `min_slice_size` 64 << 20.
    dnn_input_layer_to_tree: Whether to provide the DNN's input layer
    as a feature to the tree.
    dnn_steps_to_train: Number of steps to train dnn for before switching
      to gbdt.
    predict_with_tree_only: Whether to use only the tree model output as the
      final prediction.
    tree_feature_columns: An iterable containing all the feature columns
      used by the model's boosted trees. If dnn_input_layer_to_tree is
      set to True, these features are in addition to dnn_feature_columns.
    tree_center_bias: Whether a separate tree should be created for
      first fitting the bias.
    dnn_to_tree_distillation_param: A Tuple of (float, loss_fn), where the
      float defines the weight of the distillation loss, and the loss_fn, for
      computing distillation loss, takes dnn_logits, tree_logits and weight
      tensor. If the entire tuple is None, no distillation will be applied. If
      only the loss_fn is None, we will take the sigmoid/softmax cross entropy
      loss be default. When distillation is applied, `predict_with_tree_only`
      will be set to True.
    use_core_versions: Whether feature columns and loss are from the core (as
      opposed to contrib) version of tensorflow.

  Returns:
    A `ModelFnOps` object.
  Raises:
    ValueError: if inputs are not valid.
  """
  if not isinstance(features, dict):
    raise ValueError("features should be a dictionary of `Tensor`s. "
                     "Given type: {}".format(type(features)))

  if not dnn_feature_columns:
    raise ValueError("dnn_feature_columns must be specified")

  if dnn_to_tree_distillation_param:
    if not predict_with_tree_only:
      logging.warning("update predict_with_tree_only to True since distillation"
                      "is specified.")
      predict_with_tree_only = True

  # Build DNN Logits.
  dnn_parent_scope = "dnn"
  dnn_partitioner = dnn_input_layer_partitioner or (
      partitioned_variables.min_max_variable_partitioner(
          max_partitions=config.num_ps_replicas, min_slice_size=64 << 20))

  if (output_type == model.ModelBuilderOutputType.ESTIMATOR_SPEC and
      not use_core_versions):
    raise ValueError("You must use core versions with Estimator Spec")

#.........这里部分代码省略.........

def _dnn_model_fn(
    features, labels, mode, head, hidden_units, feature_columns,
    optimizer='Adagrad', activation_fn=nn.relu, dropout=None,
    input_layer_partitioner=None, config=None):
  """Deep Neural Net model_fn.

  Args:
    features: Dict of `Tensor` (depends on data passed to `train`).
    labels: `Tensor` of shape [batch_size, 1] or [batch_size] labels of
      dtype `int32` or `int64` in the range `[0, n_classes)`.
    mode: Defines whether this is training, evaluation or prediction.
      See `ModeKeys`.
    head: A `head_lib._Head` instance.
    hidden_units: Iterable of integer number of hidden units per layer.
    feature_columns: Iterable of `feature_column._FeatureColumn` model inputs.
    optimizer: String, `tf.Optimizer` object, or callable that creates the
      optimizer to use for training. If not specified, will use the Adagrad
      optimizer with a default learning rate of 0.05.
    activation_fn: Activation function applied to each layer.
    dropout: When not `None`, the probability we will drop out a given
      coordinate.
    input_layer_partitioner: Partitioner for input layer. Defaults
      to `min_max_variable_partitioner` with `min_slice_size` 64 << 20.
    config: `RunConfig` object to configure the runtime settings.

  Returns:
    predictions: A dict of `Tensor` objects.
    loss: A scalar containing the loss of the step.
    train_op: The op for training.
  """
  optimizer = optimizers.get_optimizer_instance(
      optimizer, learning_rate=_LEARNING_RATE)
  num_ps_replicas = config.num_ps_replicas if config else 0

  partitioner = partitioned_variables.min_max_variable_partitioner(
      max_partitions=num_ps_replicas)
  with variable_scope.variable_scope(
      'dnn',
      values=tuple(six.itervalues(features)),
      partitioner=partitioner):
    input_layer_partitioner = input_layer_partitioner or (
        partitioned_variables.min_max_variable_partitioner(
            max_partitions=num_ps_replicas,
            min_slice_size=64 << 20))
    with variable_scope.variable_scope(
        'input_from_feature_columns',
        values=tuple(six.itervalues(features)),
        partitioner=input_layer_partitioner):
      net = feature_column_lib.input_layer(
          features=features,
          feature_columns=feature_columns)

    for layer_id, num_hidden_units in enumerate(hidden_units):
      with variable_scope.variable_scope(
          'hiddenlayer_%d' % layer_id,
          values=(net,)) as hidden_layer_scope:
        net = core_layers.dense(
            net,
            units=num_hidden_units,
            activation=activation_fn,
            kernel_initializer=init_ops.glorot_uniform_initializer(),
            name=hidden_layer_scope)
        if dropout is not None and mode == model_fn.ModeKeys.TRAIN:
          net = core_layers.dropout(net, rate=dropout, training=True)
      _add_hidden_layer_summary(net, hidden_layer_scope.name)

    with variable_scope.variable_scope(
        'logits',
        values=(net,)) as logits_scope:
      logits = core_layers.dense(
          net,
          units=head.logits_dimension,
          activation=None,
          kernel_initializer=init_ops.glorot_uniform_initializer(),
          name=logits_scope)
    _add_hidden_layer_summary(logits, logits_scope.name)

    def _train_op_fn(loss):
      """Returns the op to optimize the loss."""
      return optimizer.minimize(
          loss,
          global_step=training_util.get_global_step())

    return head.create_estimator_spec(
        features=features,
        mode=mode,
        labels=labels,
        train_op_fn=_train_op_fn,
        logits=logits)

  def _process_exogenous_features(self, times, features):
    """Create a single vector from exogenous features.

    Args:
      times: A [batch size, window size] vector of times for this batch,
          primarily used to check the shape information of exogenous features.
      features: A dictionary of exogenous features corresponding to the columns
          in self._exogenous_feature_columns. Each value should have a shape
          prefixed by [batch size, window size].
    Returns:
      A Tensor with shape [batch size, window size, exogenous dimension], where
      the size of the exogenous dimension depends on the exogenous feature
      columns passed to the model's constructor.
    Raises:
      ValueError: If an exogenous feature has an unknown rank.
    """
    if self._exogenous_feature_columns:
      exogenous_features_single_batch_dimension = {}
      for name, tensor in features.items():
        if tensor.get_shape().ndims is None:
          # input_from_feature_columns does not support completely unknown
          # feature shapes, so we save on a bit of logic and provide a better
          # error message by checking that here.
          raise ValueError(
              ("Features with unknown rank are not supported. Got shape {} for "
               "feature {}.").format(tensor.get_shape(), name))
        tensor_shape_dynamic = array_ops.shape(tensor)
        tensor = array_ops.reshape(
            tensor,
            array_ops.concat([[tensor_shape_dynamic[0]
                               * tensor_shape_dynamic[1]],
                              tensor_shape_dynamic[2:]], axis=0))
        # Avoid shape warnings when embedding "scalar" exogenous features (those
        # with only batch and window dimensions); input_from_feature_columns
        # expects input ranks to match the embedded rank.
        if tensor.get_shape().ndims == 1 and tensor.dtype != dtypes.string:
          exogenous_features_single_batch_dimension[name] = tensor[:, None]
        else:
          exogenous_features_single_batch_dimension[name] = tensor
      embedded_exogenous_features_single_batch_dimension = (
          feature_column.input_layer(
              features=exogenous_features_single_batch_dimension,
              feature_columns=self._exogenous_feature_columns,
              trainable=True))
      exogenous_regressors = array_ops.reshape(
          embedded_exogenous_features_single_batch_dimension,
          array_ops.concat(
              [
                  array_ops.shape(times), array_ops.shape(
                      embedded_exogenous_features_single_batch_dimension)[1:]
              ],
              axis=0))
      exogenous_regressors.set_shape(times.get_shape().concatenate(
          embedded_exogenous_features_single_batch_dimension.get_shape()[1:]))
      exogenous_regressors = math_ops.cast(
          exogenous_regressors, dtype=self.dtype)
    else:
      # Not having any exogenous features is a special case so that models can
      # avoid superfluous updates, which may not be free of side effects due to
      # bias terms in transformations.
      exogenous_regressors = None
    return exogenous_regressors

def _dnn_linear_combined_model_fn(features, labels, mode, params, config=None):
  """Deep Neural Net and Linear combined model_fn.

  Args:
    features: `Tensor` or dict of `Tensor` (depends on data passed to `fit`).
    labels: `Tensor` of shape [batch_size, 1] or [batch_size] labels of dtype
      `int32` or `int64` in the range `[0, n_classes)`.
    mode: Defines whether this is training, evaluation or prediction.
      See `ModeKeys`.
    params: A dict of hyperparameters.
      The following hyperparameters are expected:
      * head: A `Head` instance.
      * linear_feature_columns: An iterable containing all the feature columns
          used by the Linear model.
      * linear_optimizer: string, `Optimizer` object, or callable that defines
          the optimizer to use for training the Linear model. Defaults to the
          Ftrl optimizer.
      * joint_linear_weights: If True a single (possibly partitioned) variable
          will be used to store the linear model weights. It's faster, but
          requires all columns are sparse and have the 'sum' combiner.
      * dnn_feature_columns: An iterable containing all the feature columns used
          by the DNN model.
      * dnn_optimizer: string, `Optimizer` object, or callable that defines the
          optimizer to use for training the DNN model. Defaults to the Adagrad
          optimizer.
      * dnn_hidden_units: List of hidden units per DNN layer.
      * dnn_activation_fn: Activation function applied to each DNN layer. If
          `None`, will use `tf.nn.relu`.
      * dnn_dropout: When not `None`, the probability we will drop out a given
          DNN coordinate.
      * gradient_clip_norm: A float > 0. If provided, gradients are
          clipped to their global norm with this clipping ratio.
      * embedding_lr_multipliers: Optional. A dictionary from
          `EmbeddingColumn` to a `float` multiplier. Multiplier will be used to
          multiply with learning rate for the embedding variables.
      * input_layer_partitioner: Optional. Partitioner for input layer.
    config: `RunConfig` object to configure the runtime settings.

  Returns:
    `ModelFnOps`

  Raises:
    ValueError: If both `linear_feature_columns` and `dnn_features_columns`
      are empty at the same time, or `input_layer_partitioner` is missing.
  """
  head = params["head"]
  linear_feature_columns = params.get("linear_feature_columns")
  linear_optimizer = params.get("linear_optimizer") or "Ftrl"
  joint_linear_weights = params.get("joint_linear_weights")
  dnn_feature_columns = params.get("dnn_feature_columns")
  dnn_optimizer = params.get("dnn_optimizer") or "Adagrad"
  dnn_hidden_units = params.get("dnn_hidden_units")
  dnn_activation_fn = params.get("dnn_activation_fn") or nn.relu
  dnn_dropout = params.get("dnn_dropout")
  gradient_clip_norm = params.get("gradient_clip_norm")
  num_ps_replicas = config.num_ps_replicas if config else 0
  input_layer_partitioner = params.get("input_layer_partitioner") or (
      partitioned_variables.min_max_variable_partitioner(
          max_partitions=num_ps_replicas,
          min_slice_size=64 << 20))
  embedding_lr_multipliers = params.get("embedding_lr_multipliers", {})
  fix_global_step_increment_bug = params.get(
      "fix_global_step_increment_bug", True)

  if not linear_feature_columns and not dnn_feature_columns:
    raise ValueError(
        "Either linear_feature_columns or dnn_feature_columns must be defined.")

  features = _get_feature_dict(features)

  linear_optimizer = _get_optimizer(linear_optimizer)
  _check_no_sync_replicas_optimizer(linear_optimizer)
  dnn_optimizer = _get_optimizer(dnn_optimizer)
  _check_no_sync_replicas_optimizer(dnn_optimizer)

  # Build DNN Logits.
  dnn_parent_scope = "dnn"

  if not dnn_feature_columns:
    dnn_logits = None
  else:
    if not dnn_hidden_units:
      raise ValueError(
          "dnn_hidden_units must be defined when dnn_feature_columns is "
          "specified.")
    dnn_partitioner = (
        partitioned_variables.min_max_variable_partitioner(
            max_partitions=num_ps_replicas))
    with variable_scope.variable_scope(
        dnn_parent_scope,
        values=tuple(six.itervalues(features)),
        partitioner=dnn_partitioner):
      with variable_scope.variable_scope(
          "input_from_feature_columns",
          values=tuple(six.itervalues(features)),
          partitioner=input_layer_partitioner) as dnn_input_scope:
        if all([
            isinstance(fc, feature_column_lib._FeatureColumn)  # pylint: disable=protected-access
            for fc in dnn_feature_columns
        ]):
#.........这里部分代码省略.........

def _dnn_linear_combined_model_fn(
    features, labels, mode, head,
    linear_feature_columns=None, linear_optimizer='Ftrl',
    dnn_feature_columns=None, dnn_optimizer='Adagrad', dnn_hidden_units=None,
    dnn_activation_fn=nn.relu, dnn_dropout=None,
    input_layer_partitioner=None, config=None):
  """Deep Neural Net and Linear combined model_fn.

  Args:
    features: `Tensor` or dict of `Tensor` (depends on data passed to `fit`).
    labels: `Tensor` of shape [batch_size, 1] or [batch_size] labels of dtype
      `int32` or `int64` in the range `[0, n_classes)`.
    mode: Defines whether this is training, evaluation or prediction.
      See `ModeKeys`.
    head: A `Head` instance.
    linear_feature_columns: An iterable containing all the feature columns used
      by the Linear model.
    linear_optimizer: string, `Optimizer` object, or callable that defines the
      optimizer to use for training the Linear model. Defaults to the Ftrl
      optimizer.
    dnn_feature_columns: An iterable containing all the feature columns used by
      the DNN model.
    dnn_optimizer: string, `Optimizer` object, or callable that defines the
      optimizer to use for training the DNN model. Defaults to the Adagrad
      optimizer.
    dnn_hidden_units: List of hidden units per DNN layer.
    dnn_activation_fn: Activation function applied to each DNN layer. If `None`,
      will use `tf.nn.relu`.
    dnn_dropout: When not `None`, the probability we will drop out a given DNN
      coordinate.
    input_layer_partitioner: Partitioner for input layer.
    config: `RunConfig` object to configure the runtime settings.

  Returns:
    `ModelFnOps`

  Raises:
    ValueError: If both `linear_feature_columns` and `dnn_features_columns`
      are empty at the same time, or `input_layer_partitioner` is missing.
  """
  if not linear_feature_columns and not dnn_feature_columns:
    raise ValueError(
        'Either linear_feature_columns or dnn_feature_columns must be defined.')
  num_ps_replicas = config.num_ps_replicas if config else 0
  input_layer_partitioner = input_layer_partitioner or (
      partitioned_variables.min_max_variable_partitioner(
          max_partitions=num_ps_replicas,
          min_slice_size=64 << 20))

  # Build DNN Logits.
  dnn_parent_scope = 'dnn'

  if not dnn_feature_columns:
    dnn_logits = None
  else:
    dnn_optimizer = optimizers.get_optimizer_instance(
        dnn_optimizer, learning_rate=_DNN_LEARNING_RATE)
    _check_no_sync_replicas_optimizer(dnn_optimizer)
    if not dnn_hidden_units:
      raise ValueError(
          'dnn_hidden_units must be defined when dnn_feature_columns is '
          'specified.')
    dnn_partitioner = (
        partitioned_variables.min_max_variable_partitioner(
            max_partitions=num_ps_replicas))
    with variable_scope.variable_scope(
        dnn_parent_scope,
        values=tuple(six.itervalues(features)),
        partitioner=dnn_partitioner):
      with variable_scope.variable_scope('input',
                                         partitioner=input_layer_partitioner):
        net = feature_column_lib.input_layer(
            features=features,
            feature_columns=dnn_feature_columns)

      for layer_id, num_hidden_units in enumerate(dnn_hidden_units):
        with variable_scope.variable_scope(
            'hiddenlayer_%d' % layer_id,
            values=(net,)) as dnn_hidden_layer_scope:
          net = core_layers.dense(
              net,
              units=num_hidden_units,
              activation=dnn_activation_fn,
              kernel_initializer=init_ops.glorot_uniform_initializer(),
              name=dnn_hidden_layer_scope)
          if dnn_dropout is not None and mode == model_fn.ModeKeys.TRAIN:
            net = core_layers.dropout(net, rate=dnn_dropout, training=True)
        _add_layer_summary(net, dnn_hidden_layer_scope.name)

      with variable_scope.variable_scope(
          'logits',
          values=(net,)) as dnn_logits_scope:
        dnn_logits = core_layers.dense(
            net,
            units=head.logits_dimension,
            activation=None,
            kernel_initializer=init_ops.glorot_uniform_initializer(),
            name=dnn_logits_scope)
      _add_layer_summary(dnn_logits, dnn_logits_scope.name)

#.........这里部分代码省略.........