TensorFlow

API

 tf.data / experimental / experimental.bucket_by_sequence_length


Returns the cardinality of dataset, if known.

Used in the notebooks

Used in the guide Used in the tutorials

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

dataset A tf.data.Dataset for which to determine cardinality.

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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