let summary = [{
Computes the sum of elements across dimensions of a SparseTensor.
  }];

  let description = [{
This Op takes a SparseTensor and is the sparse counterpart to
`tf.reduce_sum()`.  In particular, this Op also returns a dense `Tensor`
instead of a sparse one.

Reduces `sp_input` along the dimensions given in `reduction_axes`.  Unless

becomes `axis` * `tf.reduce_mean`: `reduction_indices` becomes `axis` *
`tf.reduce_min`: `reduction_indices` becomes `axis` * `tf.reduce_prod`:
`reduction_indices` becomes `axis` * `tf.reduce_sum`: `reduction_indices`
becomes `axis` * `tf.reverse_sequence`: `batch_dim` becomes `batch_axis`,
`seq_dim` becomes `seq_axis` * `tf.sparse_concat`: `concat_dim` becomes `axis` *