LambdaStateScheduler

class ignite.handlers.state_param_scheduler.LambdaStateScheduler(lambda_obj, param_name, save_history=False)

Update a parameter during training by using a user defined callable object.

User defined callable object is taking an event index as input and returns parameter value.

Parameters

• lambda_obj (Any) – user defined callable object.

• param_name (str) – name of parameter to update.

• save_history (bool) – whether to log the parameter values to engine.state.param_history, (default=False).

Examples

...
engine = Engine(train_step)

class LambdaState:
    def __init__(self, initial_value, gamma):
        self.initial_value = initial_value
        self.gamma = gamma

    def __call__(self, event_index):
        return self.initial_value * self.gamma ** (event_index % 9)


param_scheduler = LambdaStateScheduler(
    param_name="param",
    lambda_obj=LambdaState(10, 0.99),
)

param_scheduler.attach(engine, Events.EPOCH_COMPLETED)

# basic handler to print scheduled state parameter
engine.add_event_handler(Events.EPOCH_COMPLETED, lambda _ : print(engine.state.param))

engine.run([0] * 8, max_epochs=2)

New in version 0.4.7.

Methods

get_param

Method to get current parameter values

get_param()

Method to get current parameter values

Returns

list of params, or scalar param

Return type

Union[List[float], float]