R: Subclass the base Keras 'Model' Class

Model {keras3}

R Documentation

Subclass the base Keras `Model` Class

Description

This is for advanced use cases where you need to subclass the base Model type, e.g., you want to override the train_step() method.

If you just want to create or define a keras model, prefer keras_model() or keras_model_sequential().

If you just want to encapsulate some custom logic and state, and don't need to customize training behavior (besides calling self$add_loss() in the call() method), prefer Layer().

Usage

Model(
  classname,
  initialize = NULL,
  call = NULL,
  train_step = NULL,
  predict_step = NULL,
  test_step = NULL,
  compute_loss = NULL,
  compute_metrics = NULL,
  ...,
  public = list(),
  private = list(),
  inherit = NULL,
  parent_env = parent.frame()
)

Arguments

`classname`	String, the name of the custom class. (Conventionally, CamelCase).
`initialize`, `call`, `train_step`, `predict_step`, `test_step`, `compute_loss`, `compute_metrics`	Optional methods that can be overridden.
`...`, `public`	Additional methods or public members of the custom class.
`private`	Named list of R objects (typically, functions) to include in instance private environments. `private` methods will have all the same symbols in scope as public methods (See section "Symbols in Scope"). Each instance will have it's own `private` environment. Any objects in `private` will be invisible from the Keras framework and the Python runtime.
`inherit`	What the custom class will subclass. By default, the base keras class.
`parent_env`	The R environment that all class methods will have as a grandparent.

Value

A model constructor function, which you can call to create an instance of the new model type.

Symbols in scope

All R function custom methods (public and private) will have the following symbols in scope:

self: The custom class instance.
super: The custom class superclass.
private: An R environment specific to the class instance. Any objects assigned here are invisible to the Keras framework.
⁠__class__⁠ and as.symbol(classname): the custom class type object.