[FEATURE] Add PruneLoserPrototypes Callback

This commit is contained in:
Jensun Ravichandran 2021-06-02 03:52:41 +02:00
parent a3f5d7d113
commit 8851d1bbc9
2 changed files with 43 additions and 0 deletions

View File

@ -2,6 +2,7 @@
from importlib.metadata import PackageNotFoundError, version
from .callbacks import PruneLoserPrototypes
from .cbc import CBC, ImageCBC
from .glvq import (
GLVQ,

View File

@ -0,0 +1,42 @@
"""Lightning Callbacks."""
import pytorch_lightning as pl
import torch
class PruneLoserPrototypes(pl.Callback):
def __init__(self,
threshold=0.01,
prune_after_epochs=10,
prune_quota_per_epoch=-1,
frequency=1,
verbose=False):
self.threshold = threshold # minimum win ratio
self.prune_after_epochs = prune_after_epochs # epochs to wait
self.prune_quota_per_epoch = prune_quota_per_epoch
self.frequency = frequency
self.verbose = verbose
def on_epoch_start(self, trainer, pl_module):
pl_module.initialize_prototype_win_ratios()
def on_epoch_end(self, trainer, pl_module):
if (trainer.current_epoch + 1) < self.prune_after_epochs:
return None
if (trainer.current_epoch + 1) % self.frequency:
return None
ratios = pl_module.prototype_win_ratios.mean(dim=0)
to_prune = torch.arange(len(ratios))[ratios < self.threshold]
if self.prune_quota_per_epoch > 0:
to_prune = to_prune[:self.prune_quota_per_epoch]
if len(to_prune) > 0:
if self.verbose:
print(f"\nPrototype win ratios: {ratios}")
print(f"Pruning prototypes at: {to_prune.tolist()}")
cur_num_protos = pl_module.num_prototypes
pl_module.remove_prototypes(indices=to_prune)
new_num_protos = pl_module.num_prototypes
if self.verbose:
print(f"`num_prototypes` reduced from {cur_num_protos} "
f"to {new_num_protos}.")
return True