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TensorFlow 1 version View source on GitHub

Stacks dynamic partitions of a Tensor or RaggedTensor.



Returns a RaggedTensor output with num_partitions rows, where the row output[i] is formed by stacking all slices data[j1...jN] such that partitions[j1...jN] = i. Slices of data are stacked in row-major order.

If num_partitions is an int (not a Tensor), then this is equivalent to tf.ragged.stack(tf.dynamic_partition(data, partitions, num_partitions)).


>>> data           = ['a', 'b', 'c', 'd', 'e']
>>> partitions     = [  3,   0,   2,   2,   3]
>>> num_partitions = 5
>>> tf.ragged.stack_dynamic_partitions(data, partitions, num_partitions)
<RaggedTensor [['b'], [], ['c', 'd'], ['a', 'e'], []]>


  • data: A Tensor or RaggedTensor containing the values to stack.
  • partitions: An int32 or int64 Tensor or RaggedTensor specifying the partition that each slice of data should be added to. partitions.shape must be a prefix of data.shape. Values must be greater than or equal to zero, and less than num_partitions. partitions is not required to be sorted.
  • num_partitions: An int32 or int64 scalar specifying the number of partitions to output. This determines the number of rows in output.
  • name: A name prefix for the returned tensor (optional).


A RaggedTensor containing the stacked partitions. The returned tensor has the same dtype as data, and its shape is [num_partitions, (D)] + data.shape[partitions.rank:], where (D) is a ragged dimension whose length is the number of data slices stacked for each partition.