transformers/tests/optimization_test.py
2019-03-18 18:29:12 +01:00

64 lines
2.1 KiB
Python

# coding=utf-8
# Copyright 2018 The Google AI Language Team Authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
import unittest
import torch
from pytorch_pretrained_bert import BertAdam, WarmupCosineWithRestartsSchedule
from matplotlib import pyplot as plt
import numpy as np
class OptimizationTest(unittest.TestCase):
def assertListAlmostEqual(self, list1, list2, tol):
self.assertEqual(len(list1), len(list2))
for a, b in zip(list1, list2):
self.assertAlmostEqual(a, b, delta=tol)
def test_adam(self):
w = torch.tensor([0.1, -0.2, -0.1], requires_grad=True)
target = torch.tensor([0.4, 0.2, -0.5])
criterion = torch.nn.MSELoss()
# No warmup, constant schedule, no gradient clipping
optimizer = BertAdam(params=[w], lr=2e-1,
weight_decay=0.0,
max_grad_norm=-1)
for _ in range(100):
loss = criterion(w, target)
loss.backward()
optimizer.step()
w.grad.detach_() # No zero_grad() function on simple tensors. we do it ourselves.
w.grad.zero_()
self.assertListAlmostEqual(w.tolist(), [0.4, 0.2, -0.5], tol=1e-2)
class WarmupCosineWithRestartsTest(unittest.TestCase):
def test_it(self):
m = WarmupCosineWithRestartsSchedule(warmup=0.2, t_total=1, cycles=3)
x = np.arange(0, 1000) / 1000
y = [m.get_lr_(xe) for xe in x]
plt.plot(y)
plt.show()
if __name__ == "__main__":
unittest.main()