/
anilkfo_cifarfs.py
231 lines (205 loc) · 8.83 KB
/
anilkfo_cifarfs.py
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
#!/usr/bin/env python3
"""
File: anilkfo_cifarfs.py
Author: Seb Arnold - seba1511.net
Email: smr.arnold@gmail.com
Github: seba-1511
Description:
Demonstrates how to use the low-level differentiable optimization utilities
to implement ANIL+KFC on CIFAR-FS.
A demonstration of the high-level API is available in:
examples/vision/metacurvature_fc100.py
"""
import random
import numpy as np
import torch
import learn2learn as l2l
class CifarCNN(torch.nn.Module):
"""
Example of a 4-layer CNN network for FC100/CIFAR-FS.
"""
def __init__(self, output_size=5, hidden_size=32, layers=4):
super(CifarCNN, self).__init__()
self.hidden_size = hidden_size
features = l2l.vision.models.ConvBase(
hidden=hidden_size,
channels=3,
max_pool=False,
layers=layers,
max_pool_factor=0.5,
)
self.features = torch.nn.Sequential(
features,
l2l.nn.Lambda(lambda x: x.mean(dim=[2, 3])),
l2l.nn.Flatten(),
)
self.linear = torch.nn.Linear(self.hidden_size, output_size, bias=True)
l2l.vision.models.maml_init_(self.linear)
def forward(self, x):
x = self.features(x)
x = self.linear(x)
return x
def accuracy(predictions, targets):
predictions = predictions.argmax(dim=1).view(targets.shape)
return (predictions == targets).sum().float() / targets.size(0)
def fast_adapt(
batch,
features,
classifier,
update,
diff_sgd,
loss,
adaptation_steps,
shots,
ways,
device):
data, labels = batch
data, labels = data.to(device), labels.to(device)
data = features(data)
# Separate data into adaptation/evalutation sets
adaptation_indices = np.zeros(data.size(0), dtype=bool)
adaptation_indices[np.arange(shots*ways) * 2] = True
evaluation_indices = torch.from_numpy(~adaptation_indices)
adaptation_indices = torch.from_numpy(adaptation_indices)
adaptation_data, adaptation_labels = data[adaptation_indices], labels[adaptation_indices]
evaluation_data, evaluation_labels = data[evaluation_indices], labels[evaluation_indices]
# Adapt the model & learned update
for step in range(adaptation_steps):
adaptation_error = loss(classifier(adaptation_data), adaptation_labels)
if step > 0: # Update the learnable update function
update_grad = torch.autograd.grad(adaptation_error,
update.parameters(),
create_graph=True,
retain_graph=True)
diff_sgd(update, update_grad)
classifier_updates = update(adaptation_error,
classifier.parameters(),
create_graph=True,
retain_graph=True)
diff_sgd(classifier, classifier_updates)
# Evaluate the adapted model
predictions = classifier(evaluation_data)
eval_error = loss(predictions, evaluation_labels)
eval_accuracy = accuracy(predictions, evaluation_labels)
return eval_error, eval_accuracy
def main(
fast_lr=0.1,
meta_lr=0.003,
num_iterations=10000,
meta_batch_size=16,
adaptation_steps=5,
shots=5,
ways=5,
cuda=1,
seed=1234
):
random.seed(seed)
np.random.seed(seed)
torch.manual_seed(seed)
device = torch.device('cpu')
if cuda and torch.cuda.device_count():
torch.cuda.manual_seed(seed)
device = torch.device('cuda')
# Create Tasksets using the benchmark interface
tasksets = l2l.vision.benchmarks.get_tasksets(
name='cifarfs',
train_samples=2*shots,
train_ways=ways,
test_samples=2*shots,
test_ways=ways,
root='~/data',
)
# Create model and learnable update
model = CifarCNN(output_size=ways)
model.to(device)
features = model.features
classifier = model.linear
kfo_transform = l2l.optim.transforms.KroneckerTransform(l2l.nn.KroneckerLinear)
fast_update = l2l.optim.ParameterUpdate(
parameters=classifier.parameters(),
transform=kfo_transform,
)
fast_update.to(device)
diff_sgd = l2l.optim.DifferentiableSGD(lr=fast_lr)
all_parameters = list(model.parameters()) + list(fast_update.parameters())
opt = torch.optim.Adam(all_parameters, meta_lr)
loss = torch.nn.CrossEntropyLoss(reduction='mean')
for iteration in range(num_iterations):
opt.zero_grad()
meta_train_error = 0.0
meta_train_accuracy = 0.0
meta_valid_error = 0.0
meta_valid_accuracy = 0.0
for task in range(meta_batch_size):
# Compute meta-training loss
task_features = l2l.clone_module(features)
task_classifier = l2l.clone_module(classifier)
task_update = l2l.clone_module(fast_update)
batch = tasksets.train.sample()
evaluation_error, evaluation_accuracy = fast_adapt(batch,
task_features,
task_classifier,
task_update,
diff_sgd,
loss,
adaptation_steps,
shots,
ways,
device)
evaluation_error.backward()
meta_train_error += evaluation_error.item()
meta_train_accuracy += evaluation_accuracy.item()
# Compute meta-validation loss
task_features = l2l.clone_module(features)
task_classifier = l2l.clone_module(classifier)
task_update = l2l.clone_module(fast_update)
batch = tasksets.validation.sample()
evaluation_error, evaluation_accuracy = fast_adapt(batch,
task_features,
task_classifier,
task_update,
diff_sgd,
loss,
adaptation_steps,
shots,
ways,
device)
meta_valid_error += evaluation_error.item()
meta_valid_accuracy += evaluation_accuracy.item()
# Print some metrics
print('\n')
print('Iteration', iteration)
print('Meta Train Error', meta_train_error / meta_batch_size)
print('Meta Train Accuracy', meta_train_accuracy / meta_batch_size)
print('Meta Valid Error', meta_valid_error / meta_batch_size)
print('Meta Valid Accuracy', meta_valid_accuracy / meta_batch_size)
# Average the accumulated gradients and optimize
for p in model.parameters():
p.grad.data.mul_(1.0 / meta_batch_size)
for p in fast_update.parameters():
p.grad.data.mul_(1.0 / meta_batch_size)
opt.step()
meta_test_error = 0.0
meta_test_accuracy = 0.0
for task in range(meta_batch_size):
# Compute meta-testing loss
task_features = l2l.clone_module(features)
task_classifier = l2l.clone_module(classifier)
task_update = l2l.clone_module(fast_update)
batch = tasksets.test.sample()
evaluation_error, evaluation_accuracy = fast_adapt(batch,
task_features,
task_classifier,
task_update,
diff_sgd,
loss,
adaptation_steps,
shots,
ways,
device)
meta_test_error += evaluation_error.item()
meta_test_accuracy += evaluation_accuracy.item()
print('Meta Test Error', meta_test_error / meta_batch_size)
print('Meta Test Accuracy', meta_test_accuracy / meta_batch_size)
if __name__ == '__main__':
main()