A sequence of categorical terms where ids use an in-memory list.
tf.feature_column.sequence_categorical_column_with_vocabulary_list(
key, vocabulary_list, dtype=None, default_value=-1, num_oov_buckets=0
)
Pass this to embedding_column
or indicator_column
to convert sequence
categorical data into dense representation for input to sequence NN, such as
RNN.
Example:
colors = sequence_categorical_column_with_vocabulary_list(
key='colors', vocabulary_list=('R', 'G', 'B', 'Y'),
num_oov_buckets=2)
colors_embedding = embedding_column(colors, dimension=3)
columns = [colors_embedding]
features = tf.io.parse_example(..., features=make_parse_example_spec(columns))
sequence_feature_layer = SequenceFeatures(columns)
sequence_input, sequence_length = sequence_feature_layer(features)
sequence_length_mask = tf.sequence_mask(sequence_length)
rnn_cell = tf.keras.layers.SimpleRNNCell(hidden_size)
rnn_layer = tf.keras.layers.RNN(rnn_cell)
outputs, state = rnn_layer(sequence_input, mask=sequence_length_mask)
Args |
key
|
A unique string identifying the input feature.
|
vocabulary_list
|
An ordered iterable defining the vocabulary. Each feature
is mapped to the index of its value (if present) in vocabulary_list .
Must be castable to dtype .
|
dtype
|
The type of features. Only string and integer types are supported.
If None , it will be inferred from vocabulary_list .
|
default_value
|
The integer ID value to return for out-of-vocabulary feature
values, defaults to -1 . This can not be specified with a positive
num_oov_buckets .
|
num_oov_buckets
|
Non-negative integer, the number of out-of-vocabulary
buckets. All out-of-vocabulary inputs will be assigned IDs in the range
[len(vocabulary_list), len(vocabulary_list)+num_oov_buckets) based on a
hash of the input value. A positive num_oov_buckets can not be specified
with default_value .
|
Returns |
A SequenceCategoricalColumn .
|
Raises |
ValueError
|
if vocabulary_list is empty, or contains duplicate keys.
|
ValueError
|
num_oov_buckets is a negative integer.
|
ValueError
|
num_oov_buckets and default_value are both specified.
|
ValueError
|
if dtype is not integer or string.
|