Defined in generated file: python/ops/gen_array_ops.py
Subtracts sparse updates
from an existing tensor according to indices
.
Aliases:
tf.compat.v1.tensor_scatter_nd_sub
tf.compat.v1.tensor_scatter_sub
tf.compat.v2.tensor_scatter_nd_sub
tf.tensor_scatter_nd_sub(
tensor,
indices,
updates,
name=None
)
This operation creates a new tensor
by subtracting sparse updates
from the passed in tensor
. This operation is very similar to tf.scatter_nd_sub
, except that the updates
are subtracted from an existing tensor
(as opposed to a variable). If the memory for the existing tensor
cannot be re-used, a copy is made and updated.
indices
is an integer tensor containing indices
into a new tensor of shape
shape
. The last dimension of indices
can be at most the rank of shape
:
indices.shape[-1] <= shape.rank
The last dimension of indices
corresponds to indices
into elements (if indices
.shape
[-1] = shape
.rank) or slices (if indices
.shape
[-1] < shape
.rank) along dimension indices
.shape
[-1] of shape
. updates
is a tensor with shape
indices.shape[:-1] + shape[indices.shape[-1]:]
The simplest form of tensor_scatter_sub is to subtract individual elements from a tensor by index. For example, say we want to insert 4 scattered elements in a rank-1 tensor with 8 elements. In Python, this scatter subtract operation would look like this:
indices = tf.constant([[4], [3], [1], [7]])
updates = tf.constant([9, 10, 11, 12])
tensor = tf.ones([8], dtype=tf.int32)
updated = tf.tensor_scatter_sub(tensor, indices, updates)
with tf.Session() as sess:
print(sess.run(scatter))
The resulting tensor would look like this:
[1, -10, 1, -9, -8, 1, 1, -11]
We can also, insert entire slices of a higher rank tensor all at once. For example, if we wanted to insert two slices in the first dimension of a rank-3 tensor with two matrices of new values. In Python, this scatter add operation would look like this:
indices = tf.constant([[0], [2]])
updates = tf.constant([[[5, 5, 5, 5], [6, 6, 6, 6],
[7, 7, 7, 7], [8, 8, 8, 8]],
[[5, 5, 5, 5], [6, 6, 6, 6],
[7, 7, 7, 7], [8, 8, 8, 8]]])
tensor = tf.ones([4, 4, 4])
updated = tf.tensor_scatter_sub(tensor, indices, updates)
with tf.Session() as sess:
print(sess.run(scatter))
The resulting tensor would look like this:
[[[-4, -4, -4, -4], [-5, -5, -5, -5], [-6, -6, -6, -6], [-7, -7, -7, -7]],
[[1, 1, 1, 1], [1, 1, 1, 1], [1, 1, 1, 1], [1, 1, 1, 1]],
[[-4, -4, -4, -4], [-5, -5, -5, -5], [-6, -6, -6, -6], [-7, -7, -7, -7]],
[[1, 1, 1, 1], [1, 1, 1, 1], [1, 1, 1, 1], [1, 1, 1, 1]]]
Note that on CPU, if an out of bound index is found, an error is returned. On GPU, if an out of bound index is found, the index is ignored.
Args:
tensor
: ATensor
.Tensor
to copy/update.indices
: ATensor
. Must be one of the following types:int32
,int64
. Indextensor
.updates
: ATensor
. Must have the same type astensor
. Updates to scatter into output.name
: Aname
for the operation (optional).
Returns:
A Tensor
. Has the same type as tensor
.