mindspore.nn.HingeEmbeddingLoss

class mindspore.nn.HingeEmbeddingLoss(margin=1.0, reduction='mean')[source]

Hinge Embedding Loss. Compute the output according to the input elements. Measures the loss given an input tensor x and a labels tensor y (containing 1 or -1). This is usually used for measuring the similarity between two inputs.

The loss function for \(n\)-th sample in the mini-batch is

\[\begin{split}l_n = \begin{cases} x_n, & \text{if}\; y_n = 1,\\ \max \{0, \Delta - x_n\}, & \text{if}\; y_n = -1, \end{cases}\end{split}\]

and the total loss functions is

\[\begin{split}\ell(x, y) = \begin{cases} \operatorname{mean}(L), & \text{if reduction} = \text{'mean';}\\ \operatorname{sum}(L), & \text{if reduction} = \text{'sum'.} \end{cases}\end{split}\]

where \(L = \{l_1,\dots,l_N\}^\top\).

Parameters

  • margin (float) – Threshold defined by Hinge Embedding Loss \(margin\). Represented as \(\Delta\) in the formula. Default: 1.0.

  • reduction (str) – Specify the computing method to be applied to the outputs: ‘none’, ‘mean’, or ‘sum’. Default: ‘mean’.

Inputs:

  • logits (Tensor) - Tensor of shape \((*)\) where \(*\) means any number of dimensions.

  • labels (Tensor) - Same shape as the logits, contains -1 or 1.

Returns

Tensor or Tensor scalar, the computed loss depending on reduction.

Raises

  • TypeError – If logits is not a Tensor.

  • TypeError – If labels is not a Tensor.

  • TypeError – If margin is not a float.

  • ValueError – If labels does not have the same shape as logits.

  • ValueError – If reduction is not one of ‘none’, ‘mean’, ‘sum’.

Supported Platforms:

Ascend GPU CPU

Examplse:
>>> import numpy as np
>>> from mindspore import Tensor
>>> import mindspore.nn as nn
>>> import mindspore.common.dtype as mstype
>>> arr1 = np.array([0.9, -1.2, 2, 0.8, 3.9, 2, 1, 0, -1]).reshape((3, 3))
>>> arr2 = np.array([1, 1, -1, 1, -1, 1, -1, 1, 1]).reshape((3, 3))
>>> logits = Tensor(arr1, mstype.float32)
>>> labels = Tensor(arr2, mstype.float32)
>>> loss = nn.HingeEmbeddingLoss(reduction='mean')
>>> output = loss(logits, labels)
>>> print(output)
0.16666667