Function clone_and_build_model

tensorflow/python/keras/models.py:564–692

Clone a `Model` and build/compile it with the same settings used before. This function can be be run in the same graph or in a separate graph from the model. When using a separate graph, `in_place_reset` must be `False`. Note that, currently, the clone produced from this function may not wor

(
    model, input_tensors=None, target_tensors=None, custom_objects=None,
    compile_clone=True, in_place_reset=False, optimizer_iterations=None,
    optimizer_config=None)

def clone_and_build_model(
    model, input_tensors=None, target_tensors=None, custom_objects=None,
    compile_clone=True, in_place_reset=False, optimizer_iterations=None,
    optimizer_config=None):
  """Clone a `Model` and build/compile it with the same settings used before.

  This function can be be run in the same graph or in a separate graph from the
  model. When using a separate graph, `in_place_reset` must be `False`.

  Note that, currently, the clone produced from this function may not work with
  TPU DistributionStrategy. Try at your own risk.

  Args:
    model: `tf.keras.Model` object. Can be Functional, Sequential, or
      sub-classed.
    input_tensors: Optional list or dictionary of input tensors to build the
      model upon. If not provided, placeholders will be created.
    target_tensors: Optional list of target tensors for compiling the model. If
      not provided, placeholders will be created.
    custom_objects: Optional dictionary mapping string names to custom classes
      or functions.
    compile_clone: Boolean, whether to compile model clone (default `True`).
    in_place_reset: Boolean, whether to reset the model in place. Only used if
      the model is a subclassed model. In the case of a subclassed model,
      this argument must be set to `True` (default `False`). To restore the
      original model, use the function
      `in_place_subclassed_model_state_restoration(model)`.
    optimizer_iterations: An iterations variable that will be incremented by the
      optimizer if the clone is compiled. This argument is used when a Keras
      model is cloned into an Estimator model function, because Estimators
      create their own global step variable.
    optimizer_config: Optimizer config dictionary or list of dictionary
      returned from `get_config()`. This argument should be defined if
      `clone_and_build_model` is called in a different graph or session from
      the original model, and the optimizer is an instance of `OptimizerV2`.

  Returns:
    Clone of the model.

  Raises:
    ValueError: Cloning fails in the following cases
      - cloning a subclassed model with `in_place_reset` set to False.
      - compiling the clone when the original model has not been compiled.
  """
  # Grab optimizer now, as we reset-in-place for subclassed models, but
  # want to maintain access to the original optimizer.
  orig_optimizer = model.optimizer
  if compile_clone and not orig_optimizer:
    raise ValueError(
        'Error when cloning model: compile_clone was set to True, but the '
        'original model has not been compiled.')

  if model._is_graph_network or isinstance(model, Sequential):
    if custom_objects:
      with CustomObjectScope(custom_objects):
        clone = clone_model(model, input_tensors=input_tensors)
    else:
      clone = clone_model(model, input_tensors=input_tensors)