tf.data.experimental.cardinality

Returns the cardinality of dataset, if known.

tf.data.experimental.cardinality(
    dataset
)

Used in the notebooks

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.