Concats all tensors in the list along the 0th dimension.

Requires that all tensors have the same shape except the first dimension.

input_handle: The input list. element_shape: The shape of the uninitialized elements in the list. If the first dimension is not -1, it is assumed that all list elements have the same leading dim. leading_dims: The list of leading dims of uninitialized list elements. Used if the leading dim of input_handle.element_shape or the element_shape input arg is not already set. tensor: The concated result. lengths: Output tensor containing sizes of the 0th dimension of tensors in the list, used for computing the gradient.

input_handle A Tensor of type variant.
element_shape A Tensor. Must be one of the following types: int32, int64.
leading_dims A Tensor of type int64.
element_dtype A tf.DType.
name A name for the operation (optional).

A tuple of Tensor objects (tensor, lengths).
tensor A Tensor of type element_dtype.
lengths A Tensor of type int64.