ai-privacy-toolkit/tests/test_pytorch.py
abigailt 8b8b461143 Support for multi-label logits/probabilities
Signed-off-by: abigailt <abigailt@il.ibm.com>
2024-03-17 11:49:05 +02:00

238 lines
8.6 KiB
Python

import numpy as np
from torch import nn, optim, sigmoid, where, from_numpy
from torch.nn import functional
from torch.utils.data import DataLoader, TensorDataset
from scipy.special import expit
from art.utils import check_and_transform_label_format
from apt.utils.datasets.datasets import PytorchData
from apt.utils.models import ModelOutputType
from apt.utils.models.pytorch_model import PyTorchClassifier
from art.utils import load_nursery
from apt.utils import dataset_utils
class pytorch_model(nn.Module):
def __init__(self, num_classes, num_features):
super(pytorch_model, self).__init__()
self.fc1 = nn.Sequential(
nn.Linear(num_features, 1024),
nn.Tanh(), )
self.fc2 = nn.Sequential(
nn.Linear(1024, 512),
nn.Tanh(), )
self.fc3 = nn.Sequential(
nn.Linear(512, 256),
nn.Tanh(), )
self.fc4 = nn.Sequential(
nn.Linear(256, 128),
nn.Tanh(),
)
self.classifier = nn.Linear(128, num_classes)
def forward(self, x):
out = self.fc1(x)
out = self.fc2(out)
out = self.fc3(out)
out = self.fc4(out)
return self.classifier(out)
def test_pytorch_nursery_state_dict():
(x_train, y_train), (x_test, y_test), _, _ = load_nursery(test_set=0.5)
# reduce size of training set to make attack slightly better
train_set_size = 500
x_train = x_train[:train_set_size]
y_train = y_train[:train_set_size]
x_test = x_test[:train_set_size]
y_test = y_test[:train_set_size]
inner_model = pytorch_model(4, 24)
criterion = nn.CrossEntropyLoss()
optimizer = optim.Adam(inner_model.parameters(), lr=0.01)
model = PyTorchClassifier(model=inner_model,
output_type=ModelOutputType.CLASSIFIER_SINGLE_OUTPUT_CLASS_LOGITS,
loss=criterion,
optimizer=optimizer,
input_shape=(24,),
nb_classes=4)
model.fit(PytorchData(x_train.astype(np.float32), y_train), save_entire_model=False, nb_epochs=10)
model.load_latest_state_dict_checkpoint()
score = model.score(PytorchData(x_test.astype(np.float32), y_test))
print('Base model accuracy: ', score)
assert (0 <= score <= 1)
# python pytorch numpy
model.load_best_state_dict_checkpoint()
score = model.score(PytorchData(x_test.astype(np.float32), y_test), apply_non_linearity=expit)
print('best model accuracy: ', score)
assert (0 <= score <= 1)
def test_pytorch_nursery_save_entire_model():
(x_train, y_train), (x_test, y_test), _, _ = load_nursery(test_set=0.5)
# reduce size of training set to make attack slightly better
train_set_size = 500
x_train = x_train[:train_set_size]
y_train = y_train[:train_set_size]
x_test = x_test[:train_set_size]
y_test = y_test[:train_set_size]
model = pytorch_model(4, 24)
# model = torch.nn.DataParallel(model)
criterion = nn.CrossEntropyLoss()
optimizer = optim.Adam(model.parameters(), lr=0.01)
art_model = PyTorchClassifier(model=model,
output_type=ModelOutputType.CLASSIFIER_SINGLE_OUTPUT_CLASS_LOGITS,
loss=criterion,
optimizer=optimizer,
input_shape=(24,),
nb_classes=4)
art_model.fit(PytorchData(x_train.astype(np.float32), y_train), save_entire_model=True, nb_epochs=10)
score = art_model.score(PytorchData(x_test.astype(np.float32), y_test))
print('Base model accuracy: ', score)
assert (0 <= score <= 1)
art_model.load_best_model_checkpoint()
score = art_model.score(PytorchData(x_test.astype(np.float32), y_test), apply_non_linearity=expit)
print('best model accuracy: ', score)
assert (0 <= score <= 1)
def test_pytorch_predictions_multi_label_cat():
# This kind of model requires special training and will not be supported using the 'fit' method.
class multi_label_cat_model(nn.Module):
def __init__(self, num_classes, num_features):
super(multi_label_cat_model, self).__init__()
self.fc1 = nn.Sequential(
nn.Linear(num_features, 256),
nn.Tanh(), )
self.classifier1 = nn.Linear(256, num_classes)
self.classifier2 = nn.Linear(256, num_classes)
def forward(self, x):
out1 = self.classifier1(self.fc1(x))
out2 = self.classifier2(self.fc1(x))
return out1, out2
(x_train, y_train), (x_test, y_test) = dataset_utils.get_iris_dataset_np()
# make multi-label categorical
num_classes = 3
y_train = check_and_transform_label_format(y_train, nb_classes=num_classes)
y_test = check_and_transform_label_format(y_test, nb_classes=num_classes)
y_train = np.column_stack((y_train, y_train))
y_test = np.stack([y_test, y_test], axis=1)
test = PytorchData(x_test.astype(np.float32), y_test.astype(np.float32))
model = multi_label_cat_model(num_classes, 4)
criterion = nn.CrossEntropyLoss()
optimizer = optim.Adam(model.parameters(), lr=0.01)
# train model
train_dataset = TensorDataset(from_numpy(x_train.astype(np.float32)), from_numpy(y_train.astype(np.float32)))
train_loader = DataLoader(train_dataset, batch_size=100, shuffle=True)
for epoch in range(5):
# Train for one epoch
for inputs, targets in train_loader:
# Zero the parameter gradients
optimizer.zero_grad()
# Perform prediction
model_outputs = model(inputs)
# Form the loss function
loss = 0
for i, o in enumerate(model_outputs):
t = targets[:, i*num_classes:(i+1)*num_classes]
loss += criterion(o, t)
loss.backward()
optimizer.step()
art_model = PyTorchClassifier(model=model,
output_type=ModelOutputType.CLASSIFIER_MULTI_OUTPUT_CLASS_LOGITS,
loss=criterion,
optimizer=optimizer,
input_shape=(24,),
nb_classes=3)
pred = art_model.predict(test)
assert (pred.shape[0] == x_test.shape[0])
score = art_model.score(test, apply_non_linearity=expit)
assert (0 < score <= 1.0)
def test_pytorch_predictions_multi_label_binary():
class multi_label_binary_model(nn.Module):
def __init__(self, num_labels, num_features):
super(multi_label_binary_model, self).__init__()
self.fc1 = nn.Sequential(
nn.Linear(num_features, 256),
nn.Tanh(), )
self.classifier1 = nn.Linear(256, num_labels)
def forward(self, x):
return self.classifier1(self.fc1(x))
# missing sigmoid on each output
class FocalLoss(nn.Module):
def __init__(self, gamma=2, alpha=0.5):
super(FocalLoss, self).__init__()
self.gamma = gamma
self.alpha = alpha
def forward(self, input, target):
bce_loss = functional.binary_cross_entropy_with_logits(input, target, reduction='none')
p = sigmoid(input)
p = where(target >= 0.5, p, 1-p)
modulating_factor = (1 - p)**self.gamma
alpha = self.alpha * target + (1 - self.alpha) * (1 - target)
focal_loss = alpha * modulating_factor * bce_loss
return focal_loss.mean()
(x_train, y_train), (x_test, y_test) = dataset_utils.get_iris_dataset_np()
# make multi-label binary
y_train = np.column_stack((y_train, y_train, y_train))
y_train[y_train > 1] = 1
y_test = np.column_stack((y_test, y_test, y_test))
y_test[y_test > 1] = 1
test = PytorchData(x_test.astype(np.float32), y_test)
model = multi_label_binary_model(3, 4)
criterion = FocalLoss()
optimizer = optim.RMSprop(model.parameters(), lr=0.01)
art_model = PyTorchClassifier(model=model,
output_type=ModelOutputType.CLASSIFIER_MULTI_OUTPUT_BINARY_LOGITS,
loss=criterion,
optimizer=optimizer,
input_shape=(24,),
nb_classes=3)
art_model.fit(PytorchData(x_train.astype(np.float32), y_train.astype(np.float32)), save_entire_model=False,
nb_epochs=10)
pred = art_model.predict(test)
assert (pred.shape[0] == x_test.shape[0])
score = art_model.score(test, apply_non_linearity=expit)
assert (score == 1.0)