Retrieving The Next Element From Tf.data.dataset In Tensorflow 2.0 Beta

Before tensorflow 2.0-beta, to retrieve the first element from tf.data.Dataset, we may use a iterator as shown below: #!/usr/bin/python import tensorflow as tf train_dataset = tf

Solution 1:

What works with eager execution enabled (default in TF 2.0) is:

elem = next(iter(train_dataset))

Explanation: Datasets have an __iter__ member function to support the for elem in dataset: approach. This returns an iterator. The Python function iter does just that: Basically calls the __iter__ function. next then returns the first element that iterator produces.

I haven't found a solution which works for non-eager execution though, as that currently raises RuntimeError: __iter__() is only supported inside of tf.function or when eager execution is enabled.

Solution 2:

You can .take(1) from the dataset:

for elem in train_dataset.take(1):
  print (elem.numpy())