Register a Custom Keras Optimizer

Allows users to register a custom optimizer function so it can be used by name within kerasnip model specifications and tuned with dials.

Usage

register_keras_optimizer(name, optimizer_fn)

Arguments

name

The name to register the optimizer under (character).

optimizer_fn

The optimizer function. It should return a Keras optimizer object.

Value

No return value, called for side effects.

Details

Registered optimizers are stored in an internal environment. When a model is compiled, kerasnip will first check this internal registry for an optimizer matching the provided name before checking the keras3 package.

The optimizer_fn can be a simple function or a partially applied function using purrr::partial(). This is useful for creating versions of Keras optimizers with specific settings.

See also

register_keras_loss(), register_keras_metric()

Examples

if (requireNamespace("keras3", quietly = TRUE)) {
  # Register a custom version of Adam with a different default beta_1
  my_adam <- purrr::partial(keras3::optimizer_adam, beta_1 = 0.8)
  register_keras_optimizer("my_adam", my_adam)

  # Now "my_adam" can be used as a string in a model spec, e.g.,
  # my_model_spec(compile_optimizer = "my_adam")
}