paddle. scatter_nd_add ( ref, index, updates, name=None ) [source]

Output is obtained by applying sparse addition to a single value or slice in a Variable.

ref is a Tensor with rank $$R$$ and index is a Tensor with rank $$K$$ . Thus, index has shape $$[i_0, i_1, ..., i_{K-2}, Q]$$ where $$Q \leq R$$ . updates is a Tensor with rank $$K - 1 + R - Q$$ and its shape is $$index.shape[:-1] + ref.shape[index.shape[-1]:]$$ .

According to the $$[i_0, i_1, ..., i_{K-2}]$$ of index , add the corresponding updates slice to the ref slice which is obtained by the last one dimension of index .

Given:

* Case 1:
ref = [0, 1, 2, 3, 4, 5]
index = [[1], [2], [3], [1]]
updates = [9, 10, 11, 12]

we get:

output = [0, 22, 12, 14, 4, 5]

* Case 2:
ref = [[65, 17], [-14, -25]]
index = [[], []]
updates = [[[-1, -2], [1, 2]],
[[3, 4], [-3, -4]]]
ref.shape = (2, 2)
index.shape = (2, 0)

we get:

output = [[67, 19], [-16, -27]]

Parameters
• ref (Variable) – The ref input. Its dtype should be float32, float64.

• index (Variable) – The index input with rank > 1 and index.shape[-1] <= ref.rank. Its dtype should be int32 or int64 as it is used as indexes.

• updates (Variable) – The updated value of scatter_nd_add op, and it must have the same dtype as ref. It must have the shape index.shape[:-1] + ref.shape[index.shape[-1]:].

• name (str|None) – The output variable name. If set None, the layer will be named automatically.

Returns

The output is a tensor with the same shape and dtype as ref.

Return type

output (Variable)

Examples

import paddle.fluid as fluid