def test_few_instances_per_epoch(self):
# pylint: disable=protected-access
for test_instances in (self.instances, self.lazy_instances):
iterator = BasicIterator(batch_size=2, instances_per_epoch=3)
# First epoch: 3 instances -> [2, 1]
batches = list(
iterator._create_batches(test_instances, shuffle=False))
grouped_instances = [batch.instances for batch in batches]
assert grouped_instances == [[
self.instances[0], self.instances[1]
], [self.instances[2]]]
# Second epoch: 3 instances -> [2, 1]
batches = list(
iterator._create_batches(test_instances, shuffle=False))
grouped_instances = [batch.instances for batch in batches]
assert grouped_instances == [[
self.instances[3], self.instances[4]
], [self.instances[0]]]
# Third epoch: 3 instances -> [2, 1]
batches = list(
iterator._create_batches(test_instances, shuffle=False))
grouped_instances = [batch.instances for batch in batches]
assert grouped_instances == [[
self.instances[1], self.instances[2]
], [self.instances[3]]]
def test_create_batches_groups_correctly(self):
# pylint: disable=protected-access
for test_instances in (self.instances, self.lazy_instances):
iterator = BasicIterator(batch_size=2)
batches = list(
iterator._create_batches(test_instances, shuffle=False))
grouped_instances = [batch.instances for batch in batches]
assert grouped_instances == [[
self.instances[0], self.instances[1]
], [self.instances[2], self.instances[3]], [self.instances[4]]]
def test_max_instances_in_memory(self):
# pylint: disable=protected-access
for test_instances in (self.instances, self.lazy_instances):
iterator = BasicIterator(batch_size=2, max_instances_in_memory=3)
# One epoch: 5 instances -> [2, 1, 2]
batches = list(
iterator._create_batches(test_instances, shuffle=False))
grouped_instances = [batch.instances for batch in batches]
assert grouped_instances == [[
self.instances[0], self.instances[1]
], [self.instances[2]], [self.instances[3], self.instances[4]]]
def test_shuffle(self):
# pylint: disable=protected-access
for test_instances in (self.instances, self.lazy_instances):
iterator = BasicIterator(batch_size=2, instances_per_epoch=100)
in_order_batches = list(
iterator._create_batches(test_instances, shuffle=False))
shuffled_batches = list(
iterator._create_batches(test_instances, shuffle=True))
assert len(in_order_batches) == len(shuffled_batches)
# With 100 instances, shuffling better change the order.
assert in_order_batches != shuffled_batches
# But not the counts of the instances.
in_order_counts = Counter(instance for batch in in_order_batches
for instance in batch)
shuffled_counts = Counter(instance for batch in shuffled_batches
for instance in batch)
assert in_order_counts == shuffled_counts
def test_multiple_cursors(self):
# pylint: disable=protected-access
lazy_instances1 = _LazyInstances(lambda: (i for i in self.instances))
lazy_instances2 = _LazyInstances(lambda: (i for i in self.instances))
eager_instances1 = self.instances[:]
eager_instances2 = self.instances[:]
for instances1, instances2 in [(eager_instances1, eager_instances2),
(lazy_instances1, lazy_instances2)]:
iterator = BasicIterator(batch_size=1, instances_per_epoch=2)
iterator.index_with(self.vocab)
# First epoch through dataset1
batches = list(iterator._create_batches(instances1, shuffle=False))
grouped_instances = [batch.instances for batch in batches]
assert grouped_instances == [[self.instances[0]],
[self.instances[1]]]
# First epoch through dataset2
batches = list(iterator._create_batches(instances2, shuffle=False))
grouped_instances = [batch.instances for batch in batches]
assert grouped_instances == [[self.instances[0]],
[self.instances[1]]]
# Second epoch through dataset1
batches = list(iterator._create_batches(instances1, shuffle=False))
grouped_instances = [batch.instances for batch in batches]
assert grouped_instances == [[self.instances[2]],
[self.instances[3]]]
# Second epoch through dataset2
batches = list(iterator._create_batches(instances2, shuffle=False))
grouped_instances = [batch.instances for batch in batches]
assert grouped_instances == [[self.instances[2]],
[self.instances[3]]]
def test_maximum_samples_per_batch(self):
for test_instances in (self.instances, self.lazy_instances):
# pylint: disable=protected-access
iterator = BasicIterator(
batch_size=3, maximum_samples_per_batch=['num_tokens', 9])
batches = list(
iterator._create_batches(test_instances, shuffle=False))
# ensure all instances are in a batch
grouped_instances = [batch.instances for batch in batches]
num_instances = sum(len(group) for group in grouped_instances)
assert num_instances == len(self.instances)
# ensure all batches are sufficiently small
for batch in batches:
batch_sequence_length = max([
instance.get_padding_lengths()['text']['num_tokens']
for instance in batch.instances
])
assert batch_sequence_length * len(batch.instances) <= 9