U
    ¯Ê¹j  ã                   @   s4   d Z ddlZddlZddlmZ G dd„ deƒZdS )z¯ AdamW Optimizer
Impl copied from PyTorch master

NOTE: Builtin optim.AdamW is used by the factory, this impl only serves as a Python based reference, will be removed
someday
é    N)Ú	Optimizerc                       s@   e Zd ZdZd‡ fdd„	Z‡ fd	d
„Ze ¡ ddd„ƒZ‡  Z	S )ÚAdamWaÃ  Implements AdamW algorithm.

    The original Adam algorithm was proposed in `Adam: A Method for Stochastic Optimization`_.
    The AdamW variant was proposed in `Decoupled Weight Decay Regularization`_.

    Arguments:
        params (iterable): iterable of parameters to optimize or dicts defining
            parameter groups
        lr (float, optional): learning rate (default: 1e-3)
        betas (Tuple[float, float], optional): coefficients used for computing
            running averages of gradient and its square (default: (0.9, 0.999))
        eps (float, optional): term added to the denominator to improve
            numerical stability (default: 1e-8)
        weight_decay (float, optional): weight decay coefficient (default: 1e-2)
        amsgrad (boolean, optional): whether to use the AMSGrad variant of this
            algorithm from the paper `On the Convergence of Adam and Beyond`_
            (default: False)

    .. _Adam\: A Method for Stochastic Optimization:
        https://arxiv.org/abs/1412.6980
    .. _Decoupled Weight Decay Regularization:
        https://arxiv.org/abs/1711.05101
    .. _On the Convergence of Adam and Beyond:
        https://openreview.net/forum?id=ryQu7f-RZ
    çü©ñÒMbP?©gÍÌÌÌÌÌì?g+‡ÙÎ÷ï?ç:Œ0âŽyE>ç{®Gáz„?Fc                    s¬   d|kst d |¡ƒ‚d|ks,t d |¡ƒ‚d|d   krDdk sXn t d |d ¡ƒ‚d|d   krpdk s„n t d |d ¡ƒ‚t|||||d	�}tt| ƒ ||¡ d S )
Ng        zInvalid learning rate: {}zInvalid epsilon value: {}r   g      ð?z%Invalid beta parameter at index 0: {}é   z%Invalid beta parameter at index 1: {})ÚlrÚbetasÚepsÚweight_decayÚamsgrad)Ú
ValueErrorÚformatÚdictÚsuperr   Ú__init__)ÚselfÚparamsr	   r
   r   r   r   Údefaults©Ú	__class__© úO/var/www/html/bwave/python/venv/lib/python3.8/site-packages/timm/optim/adamw.pyr   '   s     ÿzAdamW.__init__c                    s,   t t| ƒ |¡ | jD ]}| dd¡ qd S )Nr   F)r   r   Ú__setstate__Úparam_groupsÚ
setdefault)r   ÚstateÚgroupr   r   r   r   5   s    
zAdamW.__setstate__Nc              	   C   sÒ  d}|dk	r&t  ¡ � |ƒ }W 5 Q R X | jD �]ž}|d D �]Ž}|jdkrLq:|j d|d |d   ¡ |j}|jr|tdƒ‚|d }| j| }t	|ƒdkrÐd|d	< t  
|¡|d
< t  
|¡|d< |rÐt  
|¡|d< |d
 |d  }}	|rî|d }
|d \}}|d	  d7  < d||d	   }d||d	   }| |¡j|d| d� |	 |¡j||d| d� |�r�t j|
|	|
d� |
 ¡ t |¡  |d ¡}n|	 ¡ t |¡  |d ¡}|d | }|j||| d� q:q,|S )z¶Performs a single optimization step.

        Arguments:
            closure (callable, optional): A closure that reevaluates the model
                and returns the loss.
        Nr   r   r	   r   zJAdam does not support sparse gradients, please consider SparseAdam insteadr   r   ÚstepÚexp_avgÚ
exp_avg_sqÚmax_exp_avg_sqr
   )Úalpha)Úvalue)Úoutr   )ÚtorchZenable_gradr   ÚgradÚdataZmul_Z	is_sparseÚRuntimeErrorr   ÚlenZ
zeros_likeZadd_Zaddcmul_ÚmaxÚsqrtÚmathZaddcdiv_)r   ÚclosureZlossr   Úpr'   r   r   r    r!   r"   Zbeta1Zbeta2Zbias_correction1Zbias_correction2ÚdenomZ	step_sizer   r   r   r   :   sH    


z
AdamW.step)r   r   r   r   F)N)
Ú__name__Ú
__module__Ú__qualname__Ú__doc__r   r   r&   Zno_gradr   Ú__classcell__r   r   r   r   r      s       ÿr   )r4   r-   r&   Ztorch.optim.optimizerr   r   r   r   r   r   Ú<module>   s   