U
    ‰d¹*  ã                   @   sÆ   d dl Z d dlZd dlmZ ddlmZ ddlmZ ddl	m
Z ddl	mZ d d	l mZmZ d d
lmZmZmZ G dd„ deƒZG dd„ deƒZeeee ef ZG dd„ deƒZG dd„ deƒZdS )é    N)Ú	Parameteré   )ÚModule)ÚCrossMapLRN2dé   )Ú
functional)Úinit)ÚTensorÚSize)ÚUnionÚListÚTuplec                       sv   e Zd ZU dZddddgZeed< eed< eed< eed< deeeed	d
œ‡ fdd„Ze	e	dœdd„Z
dd„ Z‡  ZS )ÚLocalResponseNormau  Applies local response normalization over an input signal composed
    of several input planes, where channels occupy the second dimension.
    Applies normalization across channels.

    .. math::
        b_{c} = a_{c}\left(k + \frac{\alpha}{n}
        \sum_{c'=\max(0, c-n/2)}^{\min(N-1,c+n/2)}a_{c'}^2\right)^{-\beta}

    Args:
        size: amount of neighbouring channels used for normalization
        alpha: multiplicative factor. Default: 0.0001
        beta: exponent. Default: 0.75
        k: additive factor. Default: 1

    Shape:
        - Input: :math:`(N, C, *)`
        - Output: :math:`(N, C, *)` (same shape as input)

    Examples::

        >>> lrn = nn.LocalResponseNorm(2)
        >>> signal_2d = torch.randn(32, 5, 24, 24)
        >>> signal_4d = torch.randn(16, 5, 7, 7, 7, 7)
        >>> output_2d = lrn(signal_2d)
        >>> output_4d = lrn(signal_4d)

    ÚsizeÚalphaÚbetaÚkç-Cëâ6?ç      è?ç      ð?N©r   r   r   r   Úreturnc                    s*   t t| ƒ ¡  || _|| _|| _|| _d S ©N)Úsuperr   Ú__init__r   r   r   r   ©Úselfr   r   r   r   ©Ú	__class__© úB/tmp/pip-unpacked-wheel-ua33x9lu/torch/nn/modules/normalization.pyr   /   s
    zLocalResponseNorm.__init__©Úinputr   c                 C   s   t  || j| j| j| j¡S r   )ÚFZlocal_response_normr   r   r   r   ©r   r"   r   r   r    Úforward6   s    ÿzLocalResponseNorm.forwardc                 C   s   dj f | jŽS ©Nz){size}, alpha={alpha}, beta={beta}, k={k}©ÚformatÚ__dict__©r   r   r   r    Ú
extra_repr:   s    zLocalResponseNorm.extra_repr)r   r   r   )Ú__name__Ú
__module__Ú__qualname__Ú__doc__Ú__constants__ÚintÚ__annotations__Úfloatr   r	   r%   r+   Ú__classcell__r   r   r   r    r      s   
r   c                       sl   e Zd ZU eed< eed< eed< eed< deeeedd	œ‡ fd
d„Zeedœdd„Ze	dœdd„Z
‡  ZS )r   r   r   r   r   r   r   r   Nr   c                    s*   t t| ƒ ¡  || _|| _|| _|| _d S r   )r   r   r   r   r   r   r   r   r   r   r    r   D   s
    zCrossMapLRN2d.__init__r!   c                 C   s   t  || j| j| j| j¡S r   )Ú_cross_map_lrn2dÚapplyr   r   r   r   r$   r   r   r    r%   K   s    ÿzCrossMapLRN2d.forward©r   c                 C   s   dj f | jŽS r&   r'   r*   r   r   r    r+   O   s    zCrossMapLRN2d.extra_repr)r   r   r   )r,   r-   r.   r1   r2   r3   r   r	   r%   Ústrr+   r4   r   r   r   r    r   >   s   
r   c                       s†   e Zd ZU dZdddgZeedf ed< eed< e	ed< de
ee	dd	œ‡ fd
d„Zddœdd„Zeedœdd„Zedœdd„Z‡  ZS )Ú	LayerNormaõ  Applies Layer Normalization over a mini-batch of inputs as described in
    the paper `Layer Normalization <https://arxiv.org/abs/1607.06450>`__

    .. math::
        y = \frac{x - \mathrm{E}[x]}{ \sqrt{\mathrm{Var}[x] + \epsilon}} * \gamma + \beta

    The mean and standard-deviation are calculated over the last `D` dimensions, where `D`
    is the dimension of :attr:`normalized_shape`. For example, if :attr:`normalized_shape`
    is ``(3, 5)`` (a 2-dimensional shape), the mean and standard-deviation are computed over
    the last 2 dimensions of the input (i.e. ``input.mean((-2, -1))``).
    :math:`\gamma` and :math:`\beta` are learnable affine transform parameters of
    :attr:`normalized_shape` if :attr:`elementwise_affine` is ``True``.
    The standard-deviation is calculated via the biased estimator, equivalent to
    `torch.var(input, unbiased=False)`.

    .. note::
        Unlike Batch Normalization and Instance Normalization, which applies
        scalar scale and bias for each entire channel/plane with the
        :attr:`affine` option, Layer Normalization applies per-element scale and
        bias with :attr:`elementwise_affine`.

    This layer uses statistics computed from input data in both training and
    evaluation modes.

    Args:
        normalized_shape (int or list or torch.Size): input shape from an expected input
            of size

            .. math::
                [* \times \text{normalized\_shape}[0] \times \text{normalized\_shape}[1]
                    \times \ldots \times \text{normalized\_shape}[-1]]

            If a single integer is used, it is treated as a singleton list, and this module will
            normalize over the last dimension which is expected to be of that specific size.
        eps: a value added to the denominator for numerical stability. Default: 1e-5
        elementwise_affine: a boolean value that when set to ``True``, this module
            has learnable per-element affine parameters initialized to ones (for weights)
            and zeros (for biases). Default: ``True``.

    Attributes:
        weight: the learnable weights of the module of shape
            :math:`\text{normalized\_shape}` when :attr:`elementwise_affine` is set to ``True``.
            The values are initialized to 1.
        bias:   the learnable bias of the module of shape
                :math:`\text{normalized\_shape}` when :attr:`elementwise_affine` is set to ``True``.
                The values are initialized to 0.

    Shape:
        - Input: :math:`(N, *)`
        - Output: :math:`(N, *)` (same shape as input)

    Examples::

        >>> # NLP Example
        >>> batch, sentence_length, embedding_dim = 20, 5, 10
        >>> embedding = torch.randn(batch, sentence_length, embedding_dim)
        >>> layer_norm = nn.LayerNorm(embedding_dim)
        >>> # Activate module
        >>> layer_norm(embedding)
        >>>
        >>> # Image Example
        >>> N, C, H, W = 20, 5, 10, 10
        >>> input = torch.randn(N, C, H, W)
        >>> # Normalize over the last three dimensions (i.e. the channel and spatial dimensions)
        >>> # as shown in the image below
        >>> layer_norm = nn.LayerNorm([C, H, W])
        >>> output = layer_norm(input)

    .. image:: ../_static/img/nn/layer_norm.jpg
        :scale: 50 %

    Únormalized_shapeÚepsÚelementwise_affine.çñhãˆµøä>TN)r:   r;   r<   r   c                    s˜   ||dœ}t t| ƒ ¡  t|tjƒr*|f}t|ƒ| _|| _|| _	| j	rtt
tj| jf|Žƒ| _t
tj| jf|Žƒ| _n|  dd ¡ |  dd ¡ |  ¡  d S )N©ÚdeviceÚdtypeÚweightÚbias)r   r9   r   Ú
isinstanceÚnumbersÚIntegralÚtupler:   r;   r<   r   ÚtorchÚemptyrA   rB   Úregister_parameterÚreset_parameters)r   r:   r;   r<   r?   r@   Úfactory_kwargsr   r   r    r   ¤   s    

zLayerNorm.__init__r7   c                 C   s"   | j rt | j¡ t | j¡ d S r   )r<   r   Úones_rA   Úzeros_rB   r*   r   r   r    rJ   ·   s    zLayerNorm.reset_parametersr!   c                 C   s   t  || j| j| j| j¡S r   )r#   Z
layer_normr:   rA   rB   r;   r$   r   r   r    r%   ¼   s        ÿzLayerNorm.forwardc                 C   s   dj f | jŽS )NzF{normalized_shape}, eps={eps}, elementwise_affine={elementwise_affine}r'   r*   r   r   r    r+   À   s    ÿzLayerNorm.extra_repr)r=   TNN)r,   r-   r.   r/   r0   r   r1   r2   r3   ÚboolÚ_shape_tr   rJ   r	   r%   r8   r+   r4   r   r   r   r    r9   V   s   
H
    ÿÿr9   c                       sŠ   e Zd ZU dZddddgZeed< eed< eed< eed< deeeedd	œ‡ fd
d„Z	ddœdd„Z
eedœdd„Zedœdd„Z‡  ZS )Ú	GroupNormaŸ  Applies Group Normalization over a mini-batch of inputs as described in
    the paper `Group Normalization <https://arxiv.org/abs/1803.08494>`__

    .. math::
        y = \frac{x - \mathrm{E}[x]}{ \sqrt{\mathrm{Var}[x] + \epsilon}} * \gamma + \beta

    The input channels are separated into :attr:`num_groups` groups, each containing
    ``num_channels / num_groups`` channels. :attr:`num_channels` must be divisible by
    :attr:`num_groups`. The mean and standard-deviation are calculated
    separately over the each group. :math:`\gamma` and :math:`\beta` are learnable
    per-channel affine transform parameter vectors of size :attr:`num_channels` if
    :attr:`affine` is ``True``.
    The standard-deviation is calculated via the biased estimator, equivalent to
    `torch.var(input, unbiased=False)`.

    This layer uses statistics computed from input data in both training and
    evaluation modes.

    Args:
        num_groups (int): number of groups to separate the channels into
        num_channels (int): number of channels expected in input
        eps: a value added to the denominator for numerical stability. Default: 1e-5
        affine: a boolean value that when set to ``True``, this module
            has learnable per-channel affine parameters initialized to ones (for weights)
            and zeros (for biases). Default: ``True``.

    Shape:
        - Input: :math:`(N, C, *)` where :math:`C=\text{num\_channels}`
        - Output: :math:`(N, C, *)` (same shape as input)

    Examples::

        >>> input = torch.randn(20, 6, 10, 10)
        >>> # Separate 6 channels into 3 groups
        >>> m = nn.GroupNorm(3, 6)
        >>> # Separate 6 channels into 6 groups (equivalent with InstanceNorm)
        >>> m = nn.GroupNorm(6, 6)
        >>> # Put all 6 channels into a single group (equivalent with LayerNorm)
        >>> m = nn.GroupNorm(1, 6)
        >>> # Activating the module
        >>> output = m(input)
    Ú
num_groupsÚnum_channelsr;   Úaffiner=   TN)rQ   rR   r;   rS   r   c                    s˜   ||dœ}t t| ƒ ¡  || dkr,tdƒ‚|| _|| _|| _|| _| jrttt	j
|f|Žƒ| _tt	j
|f|Žƒ| _n|  dd ¡ |  dd ¡ |  ¡  d S )Nr>   r   z,num_channels must be divisible by num_groupsrA   rB   )r   rP   r   Ú
ValueErrorrQ   rR   r;   rS   r   rG   rH   rA   rB   rI   rJ   )r   rQ   rR   r;   rS   r?   r@   rK   r   r   r    r   ö   s    
zGroupNorm.__init__r7   c                 C   s"   | j rt | j¡ t | j¡ d S r   )rS   r   rL   rA   rM   rB   r*   r   r   r    rJ   
  s    zGroupNorm.reset_parametersr!   c                 C   s   t  || j| j| j| j¡S r   )r#   Z
group_normrQ   rA   rB   r;   r$   r   r   r    r%     s        ÿzGroupNorm.forwardc                 C   s   dj f | jŽS )Nz8{num_groups}, {num_channels}, eps={eps}, affine={affine}r'   r*   r   r   r    r+     s    ÿzGroupNorm.extra_repr)r=   TNN)r,   r-   r.   r/   r0   r1   r2   r3   rN   r   rJ   r	   r%   r8   r+   r4   r   r   r   r    rP   Å   s   
*    ÿ
ÿrP   )rG   rD   Ztorch.nn.parameterr   Úmoduler   Z
_functionsr   r5   Ú r   r#   r   r	   r
   Útypingr   r   r   r   r1   rO   r9   rP   r   r   r   r    Ú<module>   s   1o