
    קg                     t    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gZ G d de          ZdS )	    N)inf)constraints)Normal)TransformedDistribution)AbsTransform
HalfNormalc                        e Zd ZdZdej        iZej        ZdZ	d fd	Z
d fd	Zed             Zed             Zed	             Zed
             Zd Zd Zd Zd Z xZS )r   a  
    Creates a half-normal distribution parameterized by `scale` where::

        X ~ Normal(0, scale)
        Y = |X| ~ HalfNormal(scale)

    Example::

        >>> # xdoctest: +IGNORE_WANT("non-deterministic")
        >>> m = HalfNormal(torch.tensor([1.0]))
        >>> m.sample()  # half-normal distributed with scale=1
        tensor([ 0.1046])

    Args:
        scale (float or Tensor): scale of the full Normal distribution
    scaleTNc                     t          d|d          }t                                          |t                      |           d S )Nr   F)validate_args)r   super__init__r   )selfr
   r   	base_dist	__class__s       [/var/www/html/ai-engine/env/lib/python3.11/site-packages/torch/distributions/half_normal.pyr   zHalfNormal.__init__$   s@    1e5999	LNN-PPPPP    c                     |                      t          |          }t                                          ||          S )N)	_instance)_get_checked_instancer   r   expand)r   batch_shaper   newr   s       r   r   zHalfNormal.expand(   s2    ((Y??ww~~kS~999r   c                     | j         j        S N)r   r
   r   s    r   r
   zHalfNormal.scale,   s    ~##r   c                 T    | j         t          j        dt          j        z            z  S N   )r
   mathsqrtpir   s    r   meanzHalfNormal.mean0   s    zDIa$'k2222r   c                 4    t          j        | j                  S r   )torch
zeros_liker
   r   s    r   modezHalfNormal.mode4   s    
+++r   c                 \    | j                             d          ddt          j        z  z
  z  S Nr      )r
   powr    r"   r   s    r   variancezHalfNormal.variance8   s%    z~~a  ADGO44r   c                     | j         r|                     |           | j                            |          t	          j        d          z   }t          j        |dk    |t                     }|S )Nr   r   )	_validate_args_validate_sampler   log_probr    logr%   wherer   )r   valuer0   s      r   r0   zHalfNormal.log_prob<   sa     	)!!%(((>**511DHQKK?;uz8cT::r   c                 z    | j         r|                     |           d| j                            |          z  dz
  S r)   )r.   r/   r   cdf)r   r3   s     r   r5   zHalfNormal.cdfC   sA     	)!!%(((4>%%e,,,q00r   c                 B    | j                             |dz   dz            S )Nr*   r   )r   icdf)r   probs     r   r7   zHalfNormal.icdfH   s     ~""D1H>222r   c                 ^    | j                                         t          j        d          z
  S r   )r   entropyr    r1   r   s    r   r:   zHalfNormal.entropyK   s#    ~%%''$(1++55r   r   )__name__
__module____qualname____doc__r   positivearg_constraintsnonnegativesupporthas_rsampler   r   propertyr
   r#   r'   r,   r0   r5   r7   r:   __classcell__)r   s   @r   r   r      s/           45O%GKQ Q Q Q Q Q: : : : : : $ $ X$ 3 3 X3 , , X, 5 5 X5  1 1 1
3 3 36 6 6 6 6 6 6r   )r    r%   r   torch.distributionsr   torch.distributions.normalr   ,torch.distributions.transformed_distributionr   torch.distributions.transformsr   __all__r    r   r   <module>rL      s            + + + + + + - - - - - - P P P P P P 7 7 7 7 7 7 .=6 =6 =6 =6 =6( =6 =6 =6 =6 =6r   