Source code for mmengine.optim.optimizer.builder
# Copyright (c) OpenMMLab. All rights reserved.
import copy
import inspect
from typing import List, Union
import torch
import torch.nn as nn
from mmengine.config import Config, ConfigDict
from mmengine.registry import OPTIM_WRAPPER_CONSTRUCTORS, OPTIMIZERS
from .optimizer_wrapper import OptimWrapper
def register_torch_optimizers() -> List[str]:
"""Register optimizers in ``torch.optim`` to the ``OPTIMIZERS`` registry.
Returns:
List[str]: A list of registered optimizers' name.
"""
torch_optimizers = []
for module_name in dir(torch.optim):
if module_name.startswith('__'):
continue
_optim = getattr(torch.optim, module_name)
if inspect.isclass(_optim) and issubclass(_optim,
torch.optim.Optimizer):
OPTIMIZERS.register_module(module=_optim)
torch_optimizers.append(module_name)
return torch_optimizers
TORCH_OPTIMIZERS = register_torch_optimizers()
[docs]def build_optim_wrapper(model: nn.Module,
cfg: Union[dict, Config, ConfigDict]) -> OptimWrapper:
"""Build function of OptimWrapper.
If ``constructor`` is set in the ``cfg``, this method will build an
optimizer wrapper constructor, and use optimizer wrapper constructor to
build the optimizer wrapper. If ``constructor`` is not set, the
``DefaultOptimWrapperConstructor`` will be used by default.
Args:
model (nn.Module): Model to be optimized.
cfg (dict): Config of optimizer wrapper, optimizer constructor and
optimizer.
Returns:
OptimWrapper: The built optimizer wrapper.
"""
optim_wrapper_cfg = copy.deepcopy(cfg)
constructor_type = optim_wrapper_cfg.pop('constructor',
'DefaultOptimWrapperConstructor')
paramwise_cfg = optim_wrapper_cfg.pop('paramwise_cfg', None)
optim_wrapper_constructor = OPTIM_WRAPPER_CONSTRUCTORS.build(
dict(
type=constructor_type,
optim_wrapper_cfg=optim_wrapper_cfg,
paramwise_cfg=paramwise_cfg))
optim_wrapper = optim_wrapper_constructor(model)
return optim_wrapper