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tf.feature_column.categorical_column_with_hash_bucket

Represents sparse feature where ids are set by hashing.

Use this when your sparse features are in string or integer format, and you want to distribute your inputs into a finite number of buckets by hashing. output_id = Hash(input_feature_string) % bucket_size for string type input. For int type input, the value is converted to its string representation first and then hashed by the same formula.

For input dictionary features, features[key] is either Tensor or SparseTensor. If Tensor, missing values can be represented by -1 for int and '' for string, which will be dropped by this feature column.

Example:

import tensorflow as tf
keywords = tf.feature_column.categorical_column_with_hash_bucket("keywords",
10000)
columns = [keywords]
features = {'keywords': tf.constant([['Tensorflow', 'Keras', 'RNN', 'LSTM',
'CNN'], ['LSTM', 'CNN', 'Tensorflow', 'Keras', 'RNN'], ['CNN', 'Tensorflow',
'LSTM', 'Keras', 'RNN']])}
linear_prediction, _, _ = tf.compat.v1.feature_column.linear_model(features,
columns)

# or
import tensorflow as tf
keywords = tf.feature_column.categorical_column_with_hash_bucket("keywords",
10000)
keywords_embedded = tf.feature_column.embedding_column(keywords, 16)
columns = [keywords_embedded]
features = {'keywords': tf.constant([['Tensorflow', 'Keras', 'RNN', 'LSTM',
'CNN'], ['LSTM', 'CNN', 'Tensorflow', 'Keras', 'RNN'], ['CNN', 'Tensorflow',
'LSTM', 'Keras', 'RNN']])}
input_layer = tf.keras.layers.DenseFeatures(columns)
dense_tensor = input_layer(features)
Args
key A unique string identifying the input feature. It is used as the column name and the dictionary key for feature parsing configs, feature Tensor objects, and feature columns.
hash_bucket_size An int > 1. The number of buckets.
dtype The type of features. Only string and integer types are supported.
Returns
A HashedCategoricalColumn.
Raises
ValueError hash_bucket_size is not greater than 1.
ValueError dtype is neither string nor integer.

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Licensed under the Creative Commons Attribution License 4.0.
Code samples licensed under the Apache 2.0 License.
https://www.tensorflow.org/versions/r2.9/api_docs/python/tf/feature_column/categorical_column_with_hash_bucket