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dS )    )AnyN)Tensortensor)_r2_score_compute_r2_score_update)Metricc                       s   e Zd ZU dZdZeed< dZeed< dZeed< e	ed< e	ed< e	ed	< e	ed
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 fddZde	de	ddfddZde	fddZ  ZS )R2Scorea  Computes r2 score also known as `R2 Score_Coefficient Determination`_:

    .. math:: R^2 = 1 - \frac{SS_{res}}{SS_{tot}}

    where :math:`SS_{res}=\sum_i (y_i - f(x_i))^2` is the sum of residual squares, and
    :math:`SS_{tot}=\sum_i (y_i - \bar{y})^2` is total sum of squares. Can also calculate
    adjusted r2 score given by

    .. math:: R^2_{adj} = 1 - \frac{(1-R^2)(n-1)}{n-k-1}

    where the parameter :math:`k` (the number of independent regressors) should be provided as the `adjusted` argument.
    The score is only proper defined when :math:`SS_{tot}\neq 0`, which can happen for near constant targets. In this
    case a score of 0 is returned. By definition the score is bounded between 0 and 1, where 1 corresponds to the
    predictions exactly matching the targets.

    As input to ``forward`` and ``update`` the metric accepts the following input:

    - ``preds`` (:class:`~torch.Tensor`): Predictions from model in float tensor with shape ``(N,)``
      or ``(N, M)`` (multioutput)
    - ``target`` (:class:`~torch.Tensor`): Ground truth values in float tensor with shape ``(N,)``
      or ``(N, M)`` (multioutput)

    As output of ``forward`` and ``compute`` the metric returns the following output:

    - ``r2score`` (:class:`~torch.Tensor`): A tensor with the r2 score(s)

    In the case of multioutput, as default the variances will be uniformly averaged over the additional dimensions.
    Please see argument ``multioutput`` for changing this behavior.

    Args:
        num_outputs: Number of outputs in multioutput setting
        adjusted: number of independent regressors for calculating adjusted r2 score.
        multioutput: Defines aggregation in the case of multiple output scores. Can be one of the following strings:

            * ``'raw_values'`` returns full set of scores
            * ``'uniform_average'`` scores are uniformly averaged
            * ``'variance_weighted'`` scores are weighted by their individual variances
        kwargs: Additional keyword arguments, see :ref:`Metric kwargs` for more info.

    Raises:
        ValueError:
            If ``adjusted`` parameter is not an integer larger or equal to 0.
        ValueError:
            If ``multioutput`` is not one of ``"raw_values"``, ``"uniform_average"`` or ``"variance_weighted"``.

    Example:
        >>> from torchmetrics import R2Score
        >>> target = torch.tensor([3, -0.5, 2, 7])
        >>> preds = torch.tensor([2.5, 0.0, 2, 8])
        >>> r2score = R2Score()
        >>> r2score(preds, target)
        tensor(0.9486)

        >>> target = torch.tensor([[0.5, 1], [-1, 1], [7, -6]])
        >>> preds = torch.tensor([[0, 2], [-1, 2], [8, -5]])
        >>> r2score = R2Score(num_outputs=2, multioutput='raw_values')
        >>> r2score(preds, target)
        tensor([0.9654, 0.9082])
    Tis_differentiablehigher_is_betterFfull_state_updatesum_squared_error	sum_errorresidualtotal   r   uniform_averagenum_outputsadjustedmultioutputkwargsreturnNc                    s   t  jdi | || _|dk st|tstd|| _d}||vr)td| || _| jdt	
| jdd | jdt	
| jdd | jd	t	
| jdd | jd
tddd d S )Nr   z?`adjusted` parameter should be an integer larger or equal to 0.)
raw_valuesr   variance_weightedzFInvalid input to argument `multioutput`. Choose one of the following: r   sum)defaultdist_reduce_fxr   r   r    )super__init__r   
isinstanceint
ValueErrorr   r   	add_statetorchzerosr   )selfr   r   r   r   allowed_multioutput	__class__r   N/home/ubuntu/.local/lib/python3.10/site-packages/torchmetrics/regression/r2.pyr   [   s   zR2Score.__init__predstargetc                 C   sN   t ||\}}}}|  j|7  _|  j|7  _|  j|7  _|  j|7  _dS )z*Update state with predictions and targets.N)r   r   r   r   r   )r%   r*   r+   r   r   r   r   r   r   r)   updatev   s
   zR2Score.updatec                 C   s   t | j| j| j| j| j| jS )z)Computes r2 score over the metric states.)r   r   r   r   r   r   r   )r%   r   r   r)   compute   s   zR2Score.compute)r   r   r   )__name__
__module____qualname____doc__r	   bool__annotations__r
   r   r   r    strr   r   r,   r-   __classcell__r   r   r'   r)   r      s2   
 ;	r   )typingr   r#   r   r   %torchmetrics.functional.regression.r2r   r   torchmetrics.metricr   r   r   r   r   r)   <module>   s   