mindspore.Tensor.index_add

Tensor.index_add(indices, y, axis, use_lock=True, check_index_bound=True) → Tensor

Adds tensor y to specified axis and indices of tensor self. The axis should be in [-len(self.dim), len(self.dim) - 1], and indices should be in [0, the size of self - 1] at the axis dimension.

Parameters

  • indices (Tensor) – Add the value of self and y along the dimension of the axis according to the specified index value, with data type int32. The indices must be 1D with the same size as the size of y in the axis dimension. The values of indices should be in [0, b), where the b is the size of self in the axis dimension.

  • y (Tensor) – The input tensor with the value to add.

  • axis (int) – The dimension along which to index.

  • use_lock (bool, optional) – Whether to enable a lock to protect the updating process of variable tensors. If True , when updating the value of self, this process will be protected by a lock by using atomic operation. If False , the result may be unpredictable. Default: True .

  • check_index_bound (bool, optional) – If True , check indices boundary. If False , don't check indices boundary. Default: True .

Returns

Tensor, has the same shape and dtype as self.

Raises

  • TypeError – If neither indices nor y is a Tensor.

  • ValueError – If axis is out of the range of self shape.

  • ValueError – If self rank is not the same as y rank.

  • ValueError – If shape of indices is not 1D or size of indices is not equal to dimension of y[axis].

  • ValueError – If y's shape is not the same as self except the axis th dimension.

Supported Platforms:

Ascend GPU CPU

Examples

>>> import mindspore
>>> import numpy as np
>>> from mindspore import Tensor
>>> x = Tensor(np.array([[1, 2, 3], [4, 5, 6], [7, 8, 9]]), mindspore.float32)
>>> indices = Tensor(np.array([0, 2]), mindspore.int32)
>>> y = Tensor(np.array([[0.5, 1.0], [1.0, 1.5], [2.0, 2.5]]), mindspore.float32)
>>> output = x.index_add(indices, y, axis = 1)
>>> print(output)
[[ 1.5  2.   4. ]
 [ 5.   5.   7.5]
 [ 9.   8.  11.5]]
Tensor.index_add(dim, index, source, *, alpha=1) → Tensor

For details, please refer to mindspore.ops.index_add(). The corresponding relationships between the parameters of Tensor.index_add and mindspore.ops.index_add() are as follows: dim -> axis, index -> indices, source * alpha -> y.