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tf.data.experimental.cardinality

TensorFlow 1 version View source on GitHub

Returns the cardinality of dataset, if known.

tf.data.experimental.cardinality(
    dataset
)

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:

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.