mindspore.ops.cosine_embedding_loss
- mindspore.ops.cosine_embedding_loss(input1, input2, target, margin=0.0, reduction='mean')[source]
CosineEmbeddingLoss creates a criterion to measure the similarity between two tensors using cosine distance.
Given two tensors \(input1\), \(input2\), and a Tensor label \(target\) with values 1 or -1:
\[\begin{split}loss(input1, input2, target) = \begin{cases} 1-cos(input1, input2), & \text{if } target = 1\\ max(0, cos(input1, input2)-margin), & \text{if } target = -1\\ \end{cases}\end{split}\]- Parameters
input1 (Tensor) – Tensor of shape \((N, *)\) where \(*\) means, any number of additional dimensions.
input2 (Tensor) – Tensor of shape \((N, *)\), same shape and dtype as input1.
target (Tensor) – Contains value 1 or -1. Suppose the shape of input1 is \((x_1, x_2, x_3, ..., x_R)\), then the shape of target must be \((x_1, x_3, x_4, ..., x_R)\).
margin (float, optional) – Should be in [-1.0, 1.0]. Default: 0.0.
reduction (str, optional) – Specifies which reduction to be applied to the output. It must be one of
"none"
,"mean"
, and"sum"
, meaning no reduction, reduce mean and sum on output, respectively. Default:"mean"
.
- Returns
Tensor or Scalar, if reduction is “none”, its shape is the same as target. Otherwise, a scalar value will be returned.
- Raises
TypeError – If margin is not a float.
ValueError – If reduction is not one of ‘none’, ‘mean’, ‘sum’.
ValueError – If margin is not in range [-1, 1].
- Supported Platforms:
Ascend
GPU
CPU
Examples
>>> import mindspore >>> import numpy as np >>> from mindspore import Tensor, ops >>> intput1 = Tensor(np.array([[0.3, 0.8], [0.4, 0.3]]), mindspore.float32) >>> intput2 = Tensor(np.array([[0.4, 1.2], [-0.4, -0.9]]), mindspore.float32) >>> target = Tensor(np.array([1, -1]), mindspore.int32) >>> output = ops.cosine_embedding_loss(intput1, intput2, target) >>> print(output) 0.0003425479