87 lines
3.2 KiB
Python
87 lines
3.2 KiB
Python
# flake8: noqa
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import numpy as np
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from keras_core import backend
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from keras_core import testing
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from keras_core.optimizers.adamw import AdamW
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class AdamWTest(testing.TestCase):
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def test_config(self):
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optimizer = AdamW(
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learning_rate=0.5,
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weight_decay=0.008,
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beta_1=0.5,
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beta_2=0.67,
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epsilon=1e-5,
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amsgrad=True,
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)
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self.run_class_serialization_test(optimizer)
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def test_single_step(self):
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optimizer = AdamW(learning_rate=0.5)
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grads = np.array([1.0, 6.0, 7.0, 2.0])
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vars = backend.Variable([1.0, 2.0, 3.0, 4.0])
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optimizer.apply_gradients(zip([grads], [vars]))
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self.assertAllClose(
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vars, [0.4980, 1.4960, 2.494, 3.492], rtol=1e-4, atol=1e-4
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)
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def test_weight_decay(self):
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grads, var1, var2, var3 = (
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np.zeros(()),
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backend.Variable(2.0),
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backend.Variable(2.0, name="exclude"),
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backend.Variable(2.0),
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)
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optimizer_1 = AdamW(learning_rate=1.0, weight_decay=0.004)
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optimizer_1.apply_gradients(zip([grads], [var1]))
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optimizer_2 = AdamW(learning_rate=1.0, weight_decay=0.004)
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optimizer_2.exclude_from_weight_decay(var_names=["exclude"])
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optimizer_2.apply_gradients(zip([grads, grads], [var1, var2]))
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optimizer_3 = AdamW(learning_rate=1.0, weight_decay=0.004)
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optimizer_3.exclude_from_weight_decay(var_list=[var3])
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optimizer_3.apply_gradients(zip([grads, grads], [var1, var3]))
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self.assertAlmostEqual(var1.numpy(), 1.9760959, decimal=6)
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self.assertAlmostEqual(var2.numpy(), 2.0, decimal=6)
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self.assertAlmostEqual(var3.numpy(), 2.0, decimal=6)
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def test_correctness_with_golden(self):
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optimizer = AdamW(learning_rate=1.0, weight_decay=0.5, epsilon=2)
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x = backend.Variable(np.ones([10]))
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grads = np.arange(0.1, 1.1, 0.1)
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first_grads = np.full((10,), 0.01)
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# fmt: off
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golden = np.array(
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[[0.4998, 0.4998, 0.4998, 0.4998, 0.4998, 0.4998, 0.4998, 0.4998, 0.4998, 0.4998],
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[0.2486, 0.2475, 0.2463, 0.2451, 0.244, 0.2428, 0.2417, 0.2405, 0.2394, 0.2382],
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[0.1223, 0.1198, 0.1174, 0.1149, 0.1124, 0.11, 0.1075, 0.1051, 0.1027, 0.1003],
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[0.0586, 0.0549, 0.0512, 0.0475, 0.0439, 0.0402, 0.0366, 0.033, 0.0294, 0.0258],
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[0.0263, 0.0215, 0.0167, 0.012, 0.0073, 0.0026, -0.0021, -0.0067, -0.0113, -0.0159]]
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)
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# fmt: on
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optimizer.apply_gradients(zip([first_grads], [x]))
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for i in range(5):
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self.assertAllClose(x, golden[i], rtol=5e-4, atol=5e-4)
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optimizer.apply_gradients(zip([grads], [x]))
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def test_clip_norm(self):
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optimizer = AdamW(clipnorm=1)
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grad = [np.array([100.0, 100.0])]
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clipped_grad = optimizer._clip_gradients(grad)
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self.assertAllClose(clipped_grad[0], [2**0.5 / 2, 2**0.5 / 2])
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def test_clip_value(self):
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optimizer = AdamW(clipvalue=1)
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grad = [np.array([100.0, 100.0])]
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clipped_grad = optimizer._clip_gradients(grad)
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self.assertAllClose(clipped_grad[0], [1.0, 1.0])
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