def estimator_fn():
return ssre.StateSavingRnnEstimator(
constants.ProblemType.CLASSIFICATION,
num_units=num_units,
num_unroll=num_unroll,
batch_size=batch_size,
sequence_feature_columns=seq_columns,
num_classes=num_classes,
predict_probabilities=True,
model_dir=model_dir,
queue_capacity=2 + batch_size,
seed=1234)
def testLearnLyrics(self):
lyrics = 'if I go there will be trouble and if I stay it will be double'
lyrics_list = lyrics.split()
sequence_length = len(lyrics_list)
vocab = set(lyrics_list)
batch_size = 16
num_classes = len(vocab)
num_unroll = 7 # not a divisor of sequence_length
train_steps = 350
eval_steps = 30
num_units = [4]
learning_rate = 0.4
accuracy_threshold = 0.65
def get_lyrics_input_fn(seed):
def input_fn():
start = random_ops.random_uniform(
(), minval=0, maxval=sequence_length, dtype=dtypes.int32, seed=seed)
# Concatenate lyrics_list so inputs and labels wrap when start > 0.
lyrics_list_concat = lyrics_list + lyrics_list
inputs_dense = array_ops.slice(lyrics_list_concat, [start],
[sequence_length])
indices = array_ops.constant(
[[i, 0] for i in range(sequence_length)], dtype=dtypes.int64)
dense_shape = [sequence_length, 1]
inputs = sparse_tensor.SparseTensor(
indices=indices, values=inputs_dense, dense_shape=dense_shape)
table = lookup.string_to_index_table_from_tensor(
mapping=list(vocab), default_value=-1, name='lookup')
labels = table.lookup(
array_ops.slice(lyrics_list_concat, [start + 1], [sequence_length]))
return {'lyrics': inputs}, labels
return input_fn
sequence_feature_columns = [
feature_column.embedding_column(
feature_column.sparse_column_with_keys('lyrics', vocab),
dimension=8)
]
config = run_config.RunConfig(tf_random_seed=21212)
sequence_estimator = ssre.StateSavingRnnEstimator(
constants.ProblemType.CLASSIFICATION,
num_units=num_units,
cell_type='basic_rnn',
num_unroll=num_unroll,
batch_size=batch_size,
sequence_feature_columns=sequence_feature_columns,
num_classes=num_classes,
learning_rate=learning_rate,
config=config,
predict_probabilities=True,
queue_capacity=2 + batch_size,
seed=1234)
train_input_fn = get_lyrics_input_fn(seed=12321)
eval_input_fn = get_lyrics_input_fn(seed=32123)
sequence_estimator.fit(input_fn=train_input_fn, steps=train_steps)
evaluation = sequence_estimator.evaluate(
input_fn=eval_input_fn, steps=eval_steps)
accuracy = evaluation['accuracy']
self.assertGreater(accuracy, accuracy_threshold,
'Accuracy should be higher than {}; got {}'.format(
accuracy_threshold, accuracy))
def testLearnShiftByOne(self):
"""Tests that learning a 'shift-by-one' example.
Each label sequence consists of the input sequence 'shifted' by one place.
The RNN must learn to 'remember' the previous input.
"""
batch_size = 16
num_classes = 2
num_unroll = 32
sequence_length = 32
train_steps = 200
eval_steps = 20
num_units = [4]
learning_rate = 0.5
accuracy_threshold = 0.9
def get_shift_input_fn(sequence_length, seed=None):
def input_fn():
random_sequence = random_ops.random_uniform(
[sequence_length + 1], 0, 2, dtype=dtypes.int32, seed=seed)
labels = array_ops.slice(random_sequence, [0], [sequence_length])
inputs = math_ops.to_float(
array_ops.slice(random_sequence, [1], [sequence_length]))
return {'inputs': inputs}, labels
return input_fn
seq_columns = [
feature_column.real_valued_column(
'inputs', dimension=1)
]
config = run_config.RunConfig(tf_random_seed=21212)
sequence_estimator = ssre.StateSavingRnnEstimator(
constants.ProblemType.CLASSIFICATION,
num_units=num_units,
cell_type='lstm',
num_unroll=num_unroll,
batch_size=batch_size,
sequence_feature_columns=seq_columns,
num_classes=num_classes,
learning_rate=learning_rate,
config=config,
predict_probabilities=True,
queue_capacity=2 + batch_size,
seed=1234)
train_input_fn = get_shift_input_fn(sequence_length, seed=12321)
eval_input_fn = get_shift_input_fn(sequence_length, seed=32123)
sequence_estimator.fit(input_fn=train_input_fn, steps=train_steps)
evaluation = sequence_estimator.evaluate(
input_fn=eval_input_fn, steps=eval_steps)
accuracy = evaluation['accuracy']
self.assertGreater(accuracy, accuracy_threshold,
'Accuracy should be higher than {}; got {}'.format(
accuracy_threshold, accuracy))
# Testing `predict` when `predict_probabilities=True`.
prediction_dict = sequence_estimator.predict(
input_fn=eval_input_fn, as_iterable=False)
self.assertListEqual(
sorted(list(prediction_dict.keys())),
sorted([
prediction_key.PredictionKey.CLASSES,
prediction_key.PredictionKey.PROBABILITIES, ssre._get_state_name(0)
]))
predictions = prediction_dict[prediction_key.PredictionKey.CLASSES]
probabilities = prediction_dict[prediction_key.PredictionKey.PROBABILITIES]
self.assertListEqual(list(predictions.shape), [batch_size, sequence_length])
self.assertListEqual(
list(probabilities.shape), [batch_size, sequence_length, 2])
