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eZdS )    )Sequence)AnyOptionalUnion)Tensortensor)_perplexity_compute_perplexity_update)Metric)_MATPLOTLIB_AVAILABLE)_AX_TYPE_PLOT_OUT_TYPEPerplexity.plotc                       s   e Zd ZU dZdZdZdZeed< eed< 	dde	e
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PerplexityaS  Perplexity measures how well a language model predicts a text sample.

    It's calculated as the average number of bits per word a model needs to represent the sample.

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

    - ``preds`` (:class:`~torch.Tensor`): Logits or a unnormalized score assigned to each token in a sequence with shape
      [batch_size, seq_len, vocab_size], which is the output of a language model. Scores will be normalized internally
      using softmax.
    - ``target`` (:class:`~torch.Tensor`): Ground truth values with a shape [batch_size, seq_len]

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

    - ``perp`` (:class:`~torch.Tensor`): A tensor with the perplexity score

    Args:
        ignore_index: Integer specifying a target class to ignore.
            If given, this class index does not contribute to the returned score.
        kwargs:
            Additional keyword arguments, see :ref:`Metric kwargs` for more info.

    Examples:
        >>> from torch import rand, randint
        >>> from torchmetrics.text import Perplexity
        >>> preds = rand(2, 8, 5)
        >>> target = randint(5, (2, 8))
        >>> target[0, 6:] = -100
        >>> perp = Perplexity(ignore_index=-100)
        >>> perp(preds, target)
        tensor(5.8540)

    TFtotal_log_probscountNignore_indexkwargsreturnc                    sd   t  jdi | |d urt|tstd| || _| jdtddd | jdtddd d S )NzIArgument `ignore_index` expected to either be `None` or an `int` but got r   g        sum)defaultdist_reduce_fxr    )super__init__
isinstanceint
ValueErrorr   	add_stater   )selfr   r   	__class__r   Y/home/ubuntu/sommelier/.venv/lib/python3.10/site-packages/torchmetrics/text/perplexity.pyr   E   s   zPerplexity.__init__predstargetc                 C   s2   t ||| j\}}|  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"   updateQ   s   zPerplexity.updatec                 C   s   t | j| jS )zCompute the Perplexity.)r   r   r   )r   r   r   r"   computeW   s   zPerplexity.computevalaxc                 C   s   |  ||S )a  Plot a single or multiple values from the metric.

        Args:
            val: Either a single result from calling `metric.forward` or `metric.compute` or a list of these results.
                If no value is provided, will automatically call `metric.compute` and plot that result.
            ax: An matplotlib axis object. If provided will add plot to that axis

        Returns:
            Figure and Axes object

        Raises:
            ModuleNotFoundError:
                If `matplotlib` is not installed

        .. plot::
            :scale: 75

            >>> # Example plotting a single value
            >>> import torch
            >>> from torchmetrics.text import Perplexity
            >>> metric = Perplexity()
            >>> metric.update(torch.rand(2, 8, 5), torch.randint(5, (2, 8)))
            >>> fig_, ax_ = metric.plot()

        .. plot::
            :scale: 75

            >>> # Example plotting multiple values
            >>> import torch
            >>> from torchmetrics.text import Perplexity
            >>> metric = Perplexity()
            >>> values = [ ]
            >>> for _ in range(10):
            ...     values.append(metric(torch.rand(2, 8, 5), torch.randint(5, (2, 8))))
            >>> fig_, ax_ = metric.plot(values)

        )_plot)r   r'   r(   r   r   r"   plot[   s   (r   )N)NN)__name__
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