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tf.data.experimental.cardinality

Returns the cardinality of dataset, if known.

The operation returns the cardinality of dataset. The operation may return tf.data.experimental.INFINITE_CARDINALITY if dataset contains an infinite number of elements or tf.data.experimental.UNKNOWN_CARDINALITY if the analysis fails to determine the number of elements in dataset (e.g. when the dataset source is a file).

dataset = tf.data.Dataset.range(42)
print(tf.data.experimental.cardinality(dataset).numpy())
42
dataset = dataset.repeat()
cardinality = tf.data.experimental.cardinality(dataset)
print((cardinality == tf.data.experimental.INFINITE_CARDINALITY).numpy())
True
dataset = dataset.filter(lambda x: True)
cardinality = tf.data.experimental.cardinality(dataset)
print((cardinality == tf.data.experimental.UNKNOWN_CARDINALITY).numpy())
True
Args
dataset A tf.data.Dataset for which to determine cardinality.
Returns
A scalar tf.int64 Tensor representing the cardinality of dataset. If the cardinality is infinite or unknown, the operation returns the named constant INFINITE_CARDINALITY and UNKNOWN_CARDINALITY respectively.

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Licensed under the Creative Commons Attribution License 3.0.
Code samples licensed under the Apache 2.0 License.
https://www.tensorflow.org/versions/r2.4/api_docs/python/tf/data/experimental/cardinality