def test_p_val(self, p_val):
with pytest.raises(ValueError):
initial_predictions = torch.tensor([0] * 5)
take_step = take_step_with_timestep
beam_size = 3
p_sampler = TopPSampler(p=p_val, with_replacement=True)
top_k, log_probs = BeamSearch(self.end_index,
beam_size=beam_size,
max_steps=10,
sampler=p_sampler).search(
initial_predictions, {},
take_step)
def test_top_p_search(self):
initial_predictions = torch.tensor([0] * 5)
beam_size = 3
take_step = take_step_with_timestep
p_sampler = TopPSampler(p=0.8)
top_p, log_probs = BeamSearch(self.end_index,
beam_size=beam_size,
max_steps=10,
sampler=p_sampler).search(
initial_predictions, {}, take_step)
beam_size = beam_size or 1
batch_size = 5
# top_p should be shape `(batch_size, beam_size, max_predicted_length)`.
assert list(top_p.size())[:-1] == [batch_size, beam_size]
assert ((0 <= top_p) & (top_p <= 5)).all()
# log_probs should be shape `(batch_size, beam_size, max_predicted_length)`.
assert list(log_probs.size()) == [batch_size, beam_size]
def test_top_p_sampler(self):
sampler = TopPSampler(p=0.8, temperature=0.9)
probabilities, classes, state = sampler.sample_nodes(
log_probabilities, 3, {"foo": "bar"})
assert probabilities.size() == classes.size()
assert classes.size() == (2, 3)
assert all([x > 0 and x < 4 for x in classes[0]])
assert all([x > 1 and x < 5 for x in classes[1]])
# Make sure the filtered classes include the first class that exceeds p
sampler = TopPSampler(p=0.7, temperature=1.0)
probabilities, classes, state = sampler.sample_nodes(
log_probabilities, 2, {"foo": "bar"})
assert all([x == 2 or x == 3 or x == 1 for x in classes[0]])
assert all([x == 2 or x == 3 for x in classes[1]])