prototorch_models/prototorch/models/glvq.py
Alexander Engelsberger c4c51a16fe Automatic Formating.
2021-04-23 17:27:47 +02:00

85 lines
2.8 KiB
Python

import pytorch_lightning as pl
import torch
import torchmetrics
from prototorch.functions.competitions import wtac
from prototorch.functions.distances import euclidean_distance
from prototorch.functions.losses import glvq_loss
from prototorch.modules.prototypes import Prototypes1D
class GLVQ(pl.LightningModule):
"""Generalized Learning Vector Quantization."""
def __init__(self, hparams, **kwargs):
super().__init__()
self.save_hyperparameters(hparams)
self.proto_layer = Prototypes1D(
input_dim=self.hparams.input_dim,
nclasses=self.hparams.nclasses,
prototypes_per_class=self.hparams.prototypes_per_class,
prototype_initializer=self.hparams.prototype_initializer,
**kwargs)
self.train_acc = torchmetrics.Accuracy()
@property
def prototypes(self):
return self.proto_layer.prototypes.detach().numpy()
@property
def prototype_labels(self):
return self.proto_layer.prototype_labels.detach().numpy()
def configure_optimizers(self):
optimizer = torch.optim.Adam(self.parameters(), lr=self.hparams.lr)
return optimizer
def forward(self, x):
protos = self.proto_layer.prototypes
dis = euclidean_distance(x, protos)
return dis
def training_step(self, train_batch, batch_idx):
x, y = train_batch
x = x.view(x.size(0), -1)
dis = self(x)
plabels = self.proto_layer.prototype_labels
mu = glvq_loss(dis, y, prototype_labels=plabels)
loss = mu.sum(dim=0)
self.log("train_loss", loss)
with torch.no_grad():
preds = wtac(dis, plabels)
# self.train_acc.update(preds.int(), y.int())
self.train_acc(
preds.int(),
y.int()) # FloatTensors are assumed to be class probabilities
self.log(
"acc",
self.train_acc,
on_step=False,
on_epoch=True,
prog_bar=True,
logger=True,
)
return loss
# def training_epoch_end(self, outs):
# # Calling `self.train_acc.compute()` is
# # automatically done by setting `on_epoch=True` when logging in `self.training_step(...)`
# self.log("train_acc_epoch", self.train_acc.compute())
def predict(self, x):
with torch.no_grad():
# model.eval() # ?!
d = self(x)
plabels = self.proto_layer.prototype_labels
y_pred = wtac(d, plabels)
return y_pred.numpy()
class ImageGLVQ(GLVQ):
"""GLVQ model that constrains the prototypes to the range [0, 1] by
clamping after updates.
"""
def on_train_batch_end(self, outputs, batch, batch_idx, dataloader_idx):
self.proto_layer.prototypes.data.clamp_(0.0, 1.0)