from typing import Callable, Sequence, Optional, TypeVar, Union
import torch
from torch.nn import Module, CrossEntropyLoss
from torch.optim import Optimizer
from avalanche.benchmarks.scenarios.generic_scenario import DatasetExperience
from avalanche.core import BasePlugin, BaseSGDPlugin, SupervisedPlugin
from avalanche.training.plugins.evaluation import (
EvaluationPlugin,
default_evaluator,
)
from avalanche.training.templates.strategy_mixin_protocol import (
SupervisedStrategyProtocol,
)
from .observation_type import *
from .problem_type import *
from .update_type import *
from .base_sgd import BaseSGDTemplate
TDatasetExperience = TypeVar("TDatasetExperience", bound=DatasetExperience)
TMBInput = TypeVar("TMBInput")
TMBOutput = TypeVar("TMBOutput")
[docs]class SupervisedTemplate(
BatchObservation,
SupervisedProblem,
SGDUpdate,
SupervisedStrategyProtocol[TDatasetExperience, TMBInput, TMBOutput],
BaseSGDTemplate[TDatasetExperience, TMBInput, TMBOutput],
):
"""Base class for continual learning strategies.
SupervisedTemplate is the super class of all supervised task-based
continual learning strategies. It implements a basic training loop and
callback system that allows to execute code at each experience of the
training loop. Plugins can be used to implement callbacks to augment the
training loop with additional behavior (e.g. a memory buffer for replay).
**Scenarios**
This strategy supports several continual learning scenarios:
* class-incremental scenarios (no task labels)
* multi-task scenarios, where task labels are provided)
* multi-incremental scenarios, where the same task may be revisited
The exact scenario depends on the data stream and whether it provides
the task labels.
**Training loop**
The training loop is organized as follows::
train
train_exp # for each experience
adapt_train_dataset
train_dataset_adaptation
make_train_dataloader
train_epoch # for each epoch
# forward
# backward
# model update
**Evaluation loop**
The evaluation loop is organized as follows::
eval
eval_exp # for each experience
adapt_eval_dataset
eval_dataset_adaptation
make_eval_dataloader
eval_epoch # for each epoch
# forward
"""
PLUGIN_CLASS = SupervisedPlugin
[docs] def __init__(
self,
model: Module,
optimizer: Optimizer,
criterion=CrossEntropyLoss(),
train_mb_size: int = 1,
train_epochs: int = 1,
eval_mb_size: Optional[int] = 1,
device: Union[str, torch.device] = "cpu",
plugins: Optional[Sequence[BasePlugin]] = None,
evaluator: Union[
EvaluationPlugin, Callable[[], EvaluationPlugin]
] = default_evaluator,
eval_every=-1,
peval_mode="epoch",
):
"""Init.
:param model: PyTorch model.
:param optimizer: PyTorch optimizer.
:param criterion: loss function.
:param train_mb_size: mini-batch size for training. The default
dataloader is a task-balanced dataloader that divides each
mini-batch evenly between samples from all existing tasks in
the dataset.
:param train_epochs: number of training epochs.
:param eval_mb_size: mini-batch size for eval.
:param device: PyTorch device where the model will be allocated.
:param plugins: (optional) list of StrategyPlugins.
:param evaluator: (optional) instance of EvaluationPlugin for logging
and metric computations. None to remove logging.
:param eval_every: the frequency of the calls to `eval` inside the
training loop. -1 disables the evaluation. 0 means `eval` is called
only at the end of the learning experience. Values >0 mean that
`eval` is called every `eval_every` epochs and at the end of the
learning experience.
:param peval_mode: one of {'epoch', 'iteration'}. Decides whether the
periodic evaluation during training should execute every
`eval_every` epochs or iterations (Default='epoch').
"""
super().__init__() # type: ignore
BaseSGDTemplate.__init__(
self=self,
model=model,
optimizer=optimizer,
criterion=criterion,
train_mb_size=train_mb_size,
train_epochs=train_epochs,
eval_mb_size=eval_mb_size,
device=device,
plugins=plugins,
evaluator=evaluator,
eval_every=eval_every,
peval_mode=peval_mode,
)
###################################################################
# State variables. These are updated during the train/eval loops. #
###################################################################
# self.adapted_dataset = None
# """ Data used to train. It may be modified by plugins. Plugins can
# append data to it (e.g. for replay).
#
# .. note::
#
# This dataset may contain samples from different experiences. If you
# want the original data for the current experience
# use :attr:`.BaseTemplate.experience`.
class SupervisedMetaLearningTemplate(
BatchObservation,
SupervisedProblem,
MetaUpdate,
BaseSGDTemplate[TDatasetExperience, TMBInput, TMBOutput],
):
"""Base class for continual learning strategies.
SupervisedMetaLearningTemplate is the super class of all supervised
meta-learning task-based continual learning strategies. It implements a
basic training loop and callback system that allows to execute code at
each experience of the training loop. Plugins can be used to implement
callbacks to augment the training loop with additional behavior
(e.g. a memory buffer for replay).
**Scenarios**
This strategy supports several continual learning scenarios:
* class-incremental scenarios (no task labels)
* multi-task scenarios, where task labels are provided)
* multi-incremental scenarios, where the same task may be revisited
The exact scenario depends on the data stream and whether it provides
the task labels.
**Training loop**
The training loop is organized as follows::
train
train_exp # for each experience
adapt_train_dataset
train_dataset_adaptation
make_train_dataloader
train_epoch # for each epoch
# inner_updates
# outer_update
**Evaluation loop**
The evaluation loop is organized as follows::
eval
eval_exp # for each experience
adapt_eval_dataset
eval_dataset_adaptation
make_eval_dataloader
eval_epoch # for each epoch
# forward
"""
PLUGIN_CLASS = SupervisedPlugin
def __init__(
self,
model: Module,
optimizer: Optimizer,
criterion=CrossEntropyLoss(),
train_mb_size: int = 1,
train_epochs: int = 1,
eval_mb_size: Optional[int] = 1,
device: Union[str, torch.device] = "cpu",
plugins: Optional[Sequence[BasePlugin]] = None,
evaluator: Union[
EvaluationPlugin, Callable[[], EvaluationPlugin]
] = default_evaluator,
eval_every=-1,
peval_mode="epoch",
):
"""Init.
:param model: PyTorch model.
:param optimizer: PyTorch optimizer.
:param criterion: loss function.
:param train_mb_size: mini-batch size for training. The default
dataloader is a task-balanced dataloader that divides each
mini-batch evenly between samples from all existing tasks in
the dataset.
:param train_epochs: number of training epochs.
:param eval_mb_size: mini-batch size for eval.
:param device: PyTorch device where the model will be allocated.
:param plugins: (optional) list of StrategyPlugins.
:param evaluator: (optional) instance of EvaluationPlugin for logging
and metric computations. None to remove logging.
:param eval_every: the frequency of the calls to `eval` inside the
training loop. -1 disables the evaluation. 0 means `eval` is called
only at the end of the learning experience. Values >0 mean that
`eval` is called every `eval_every` epochs and at the end of the
learning experience.
:param peval_mode: one of {'epoch', 'iteration'}. Decides whether the
periodic evaluation during training should execute every
`eval_every` epochs or iterations (Default='epoch').
"""
super().__init__() # type: ignore
BaseSGDTemplate.__init__(
self=self,
model=model,
optimizer=optimizer,
criterion=criterion,
train_mb_size=train_mb_size,
train_epochs=train_epochs,
eval_mb_size=eval_mb_size,
device=device,
plugins=plugins,
evaluator=evaluator,
eval_every=eval_every,
peval_mode=peval_mode,
)
###################################################################
# State variables. These are updated during the train/eval loops. #
###################################################################
# self.adapted_dataset = None
# """ Data used to train. It may be modified by plugins. Plugins can
# append data to it (e.g. for replay).
#
# .. note::
#
# This dataset may contain samples from different experiences. If you
# want the original data for the current experience
# use :attr:`.BaseTemplate.experience`.
__all__ = [
"SupervisedTemplate",
"SupervisedMetaLearningTemplate",
]