def encode_string_categorical_feature(feature, name, dataset):
# Create a StringLookup layer which will turn strings into integer indices
index = StringLookup()
# Prepare a Dataset that only yields our feature
feature_ds = dataset.map(lambda x, y: x[name])
feature_ds = feature_ds.map(lambda x: tf.expand_dims(x, -1))
# Learn the set of possible string values and assign them a fixed integer index
index.adapt(feature_ds)
# Turn the string input into integer indices
encoded_feature = index(feature)
# Create a CategoryEncoding for our integer indices
encoder = CategoryEncoding(output_mode="binary")
# Prepare a dataset of indices
feature_ds = feature_ds.map(index)
# Learn the space of possible indices
encoder.adapt(feature_ds)
# Apply one-hot encoding to our indices
encoded_feature = encoder(encoded_feature)
return encoded_feature
def encode_string_categorical_feature(feature, name, dataset):
index = StringLookup()
feature_ds = dataset.map(lambda x, y: x[name])
feature_ds = feature_ds.map(lambda x: tf.expand_dims(x, -1))
index.adapt(feature_ds)
encoded_feature = index(feature)
encoder = CategoryEncoding(output_mode="binary")
feature_ds = feature_ds.map(index)
encoder.adapt(feature_ds)
encoded_feature = encoder(encoded_feature)
return encoded_feature
def _encode_categorical_feature(
feature: KerasTensor,
name: str,
dataset: Optional[BatchDataset],
) -> KerasTensor:
"""One-hot encode categorical features.
Args:
- feature: The input layer of the feature.
- name: The feature's name (its column name in the original dataframe).
- dataset: The training data, if not specified, return a no-op layer.
Returns:
The one-hot encoded tensor of the input feature.
"""
# Return generic layer for the tuner initialization
if not dataset:
return KerasTensor(type_spec=TensorSpec(
shape=(None, 1), dtype=tf.float32, name=None))
# Create a StringLookup layer which will turn strings into integer indices
index = StringLookup()
# Prepare a Dataset that only yields our feature
feature_ds = dataset.map(lambda x, y: x[name])
feature_ds = feature_ds.map(lambda x: tf.expand_dims(x, -1))
# Learn the set of possible string values and assign them a fixed integer index
index.adapt(feature_ds)
# Turn the string input into integer indices
encoded_feature = index(feature)
# Create a CategoryEncoding for our integer indices
encoder = CategoryEncoding(output_mode="binary")
# Learn the space of possible indices
encoder.adapt(np.arange(index.vocab_size()))
# Apply one-hot encoding to our indices{split + 1} / {n_splits}
encoded_feature = encoder(encoded_feature)
return encoded_feature
