def testBasic(self):
for dtype in [tf.complex64]:
with self.test_session():
var0 = tf.Variable([1.0, 2.0], dtype=dtype)
var1 = tf.Variable([3.0, 4.0], dtype=dtype)
grads0 = tf.constant([0.1, 0.1], dtype=dtype)
grads1 = tf.constant([0.01, 0.01], dtype=dtype)
mom_opt = tf.train.MomentumOptimizer(learning_rate=2.0, momentum=0.9)
mom_update = mom_opt.apply_gradients(
zip([grads0, grads1], [var0, var1]))
tf.global_variables_initializer().run()
# Check we have slots
self.assertEqual(["momentum"], mom_opt.get_slot_names())
slot0 = mom_opt.get_slot(var0, "momentum")
self.assertEquals(slot0.get_shape(), var0.get_shape())
self.assertFalse(slot0 in tf.trainable_variables())
slot1 = mom_opt.get_slot(var1, "momentum")
self.assertEquals(slot1.get_shape(), var1.get_shape())
self.assertFalse(slot1 in tf.trainable_variables())
# Fetch params to validate initial values
self.assertAllClose([1.0, 2.0], var0.eval())
self.assertAllClose([3.0, 4.0], var1.eval())
# Step 1: the momentum accumulators where 0. So we should see a normal
# update: v -= grad * learning_rate
mom_update.run()
# Check that the momentum accumulators have been updated.
self.assertAllCloseAccordingToType(np.array([0.1, 0.1]), slot0.eval())
self.assertAllCloseAccordingToType(np.array([0.01, 0.01]), slot1.eval())
# Check that the parameters have been updated.
self.assertAllCloseAccordingToType(np.array([1.0 - (0.1 * 2.0),
2.0 - (0.1 * 2.0)]),
var0.eval())
self.assertAllCloseAccordingToType(np.array([3.0 - (0.01 * 2.0),
4.0 - (0.01 * 2.0)]),
var1.eval())
# Step 2: the momentum accumulators contain the previous update.
mom_update.run()
# Check that the momentum accumulators have been updated.
self.assertAllCloseAccordingToType(
np.array([(0.9 * 0.1 + 0.1), (0.9 * 0.1 + 0.1)]),
slot0.eval())
self.assertAllCloseAccordingToType(
np.array([(0.9 * 0.01 + 0.01), (0.9 * 0.01 + 0.01)]),
slot1.eval())
# Check that the parameters have been updated.
self.assertAllCloseAccordingToType(
np.array([1.0 - (0.1 * 2.0) - ((0.9 * 0.1 + 0.1) * 2.0),
2.0 - (0.1 * 2.0) - ((0.9 * 0.1 + 0.1) * 2.0)]),
var0.eval())
self.assertAllCloseAccordingToType(
np.array([2.98 - ((0.9 * 0.01 + 0.01) * 2.0),
3.98 - ((0.9 * 0.01 + 0.01) * 2.0)]),
var1.eval())
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