o
    yi5                     @   sP   d dl mZ d dlZd dlmZ d dlmZmZ d dlmZ G dd deZ	dS )    )AnyN)Tensor)_tweedie_deviance_score_compute_tweedie_deviance_score_update)Metricc                       s   e Zd ZU dZdZeed< dZdZeed< e	ed< e	ed< 		dd
e
deddf fddZde	de	ddfddZde	fddZ  ZS )TweedieDevianceScorear  Computes the `Tweedie Deviance Score`_ between targets and predictions:

    .. math::
        deviance\_score(\hat{y},y) =
        \begin{cases}
        (\hat{y} - y)^2, & \text{for }p=0\\
        2 * (y * log(\frac{y}{\hat{y}}) + \hat{y} - y),  & \text{for }p=1\\
        2 * (log(\frac{\hat{y}}{y}) + \frac{y}{\hat{y}} - 1),  & \text{for }p=2\\
        2 * (\frac{(max(y,0))^{2 - p}}{(1 - p)(2 - p)} - \frac{y(\hat{y})^{1 - p}}{1 - p} + \frac{(
            \hat{y})^{2 - p}}{2 - p}), & \text{otherwise}
        \end{cases}

    where :math:`y` is a tensor of targets values, :math:`\hat{y}` is a tensor of predictions, and
    :math:`p` is the `power`.

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

    - ``preds`` (:class:`~torch.Tensor`): Predicted float tensor with shape ``(N,...)``
    - ``target`` (:class:`~torch.Tensor`): Ground truth float tensor with shape ``(N,...)``

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

    - ``deviance_score`` (:class:`~torch.Tensor`): A tensor with the deviance score

    Args:
        power:

            - power < 0 : Extreme stable distribution. (Requires: preds > 0.)
            - power = 0 : Normal distribution. (Requires: targets and preds can be any real numbers.)
            - power = 1 : Poisson distribution. (Requires: targets >= 0 and y_pred > 0.)
            - 1 < p < 2 : Compound Poisson distribution. (Requires: targets >= 0 and preds > 0.)
            - power = 2 : Gamma distribution. (Requires: targets > 0 and preds > 0.)
            - power = 3 : Inverse Gaussian distribution. (Requires: targets > 0 and preds > 0.)
            - otherwise : Positive stable distribution. (Requires: targets > 0 and preds > 0.)

        kwargs: Additional keyword arguments, see :ref:`Metric kwargs` for more info.

    Example:
        >>> from torchmetrics import TweedieDevianceScore
        >>> targets = torch.tensor([1.0, 2.0, 3.0, 4.0])
        >>> preds = torch.tensor([4.0, 3.0, 2.0, 1.0])
        >>> deviance_score = TweedieDevianceScore(power=2)
        >>> deviance_score(preds, targets)
        tensor(1.2083)
    Tis_differentiableNFfull_state_updatesum_deviance_scorenum_observations        powerkwargsreturnc                    sp   t  jd
i | d|  k rdk rn ntd| d|| _| jdtddd | jd	tddd d S )Nr      z(Deviance Score is not defined for power=.r
   r   sum)dist_reduce_fxr    )super__init__
ValueErrorr   	add_statetorchtensor)selfr   r   	__class__r   \/home/ubuntu/.local/lib/python3.10/site-packages/torchmetrics/regression/tweedie_deviance.pyr   N   s   zTweedieDevianceScore.__init__predstargetsc                 C   s2   t ||| j\}}|  j|7  _|  j|7  _dS )z2Update metric states with predictions and targets.N)r   r   r
   r   )r   r   r    r
   r   r   r   r   update\   s   zTweedieDevianceScore.updatec                 C   s   t | j| jS )N)r   r
   r   )r   r   r   r   computec   s   zTweedieDevianceScore.compute)r   )__name__
__module____qualname____doc__r   bool__annotations__higher_is_betterr	   r   floatr   r   r!   r"   __classcell__r   r   r   r   r      s"   
 -r   )
typingr   r   r   3torchmetrics.functional.regression.tweedie_deviancer   r   torchmetrics.metricr   r   r   r   r   r   <module>   s   