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torch.nn.functional.mse_loss

torch.nn.functional.mse_loss(input, target, size_average=None, reduce=None, reduction='mean', weight=None) [source]

Compute the element-wise mean squared error, with optional weighting.

See MSELoss for details.

Parameters
  • input (Tensor) – Predicted values.
  • target (Tensor) – Ground truth values.
  • size_average (bool, optional) – Deprecated (see reduction).
  • reduce (bool, optional) – Deprecated (see reduction).
  • reduction (str, optional) – Specifies the reduction to apply to the output: ‘none’ | ‘mean’ | ‘sum’. ‘mean’: the mean of the output is taken. ‘sum’: the output will be summed. ‘none’: no reduction will be applied. Default: ‘mean’.
  • weight (Tensor, optional) – Weights for each sample. Default: None.
Returns

Mean Squared Error loss (optionally weighted).

Return type

Tensor

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https://docs.pytorch.org/docs/2.9/generated/torch.nn.functional.mse_loss.html