U
    9%e@                     @   s   d Z ddlZddlmZmZmZmZ ddlZzddl	m
Z
 W n  ek
r\   ddlm
Z
 Y nX G dd dejjjjZdeeeeeeeee ee eeeee  dddZG dd de
ZG dd deZdS )z?Functions and classes related to optimization (weight updates).    N)CallableListOptionalUnion)Adamc                       s@   e Zd ZdZdeeeeed fddZdd Z	d	d
 Z
  ZS )WarmUpa  
    Applies a warmup schedule on a given learning rate decay schedule.

    Args:
        initial_learning_rate (`float`):
            The initial learning rate for the schedule after the warmup (so this will be the learning rate at the end
            of the warmup).
        decay_schedule_fn (`Callable`):
            The schedule function to apply after the warmup for the rest of training.
        warmup_steps (`int`):
            The number of steps for the warmup part of training.
        power (`float`, *optional*, defaults to 1):
            The power to use for the polynomial warmup (defaults is a linear warmup).
        name (`str`, *optional*):
            Optional name prefix for the returned tensors during the schedule.
          ?Ninitial_learning_ratedecay_schedule_fnwarmup_stepspowernamec                    s,   t    || _|| _|| _|| _|| _d S N)super__init__r
   r   r   r   r   )selfr
   r   r   r   r   	__class__ [/var/www/html/Darija-Ai-API/env/lib/python3.8/site-packages/transformers/optimization_tf.pyr   0   s    
zWarmUp.__init__c              
      s   t  jpdr}t t j}t  jt j}|| } jt j| j	 t j
||k fdd fdd|dW  5 Q R  S Q R X d S )Nr   c                      s    S r   r   r   )warmup_learning_rater   r   <lambda>I       z!WarmUp.__call__.<locals>.<lambda>c                      s      j S r   )r   r   r   )r   stepr   r   r   J   r   r   )tfZ
name_scoper   castZfloat32r   r
   mathpowr   Zcond)r   r   r   Zglobal_step_floatZwarmup_steps_floatZwarmup_percent_doner   )r   r   r   r   __call__?   s    
zWarmUp.__call__c                 C   s   | j | j| j| j| jdS )Nr	   r	   r   r   r   r   
get_configN   s    zWarmUp.get_config)r   N)__name__
__module____qualname____doc__floatr   intstrr   r    r"   __classcell__r   r   r   r   r      s     r           ?+?:0yE>r   )init_lrnum_train_stepsnum_warmup_stepsmin_lr_ratio
adam_beta1
adam_beta2adam_epsilonadam_clipnormadam_global_clipnormweight_decay_rater   include_in_weight_decayc                 C   s~   t jjjj| || | | |
d}|r2t| ||d}|	dkr\t||	|||||dddg|d	}nt jjj||||||d}||fS )	a  
    Creates an optimizer with a learning rate schedule using a warmup phase followed by a linear decay.

    Args:
        init_lr (`float`):
            The desired learning rate at the end of the warmup phase.
        num_train_steps (`int`):
            The total number of training steps.
        num_warmup_steps (`int`):
            The number of warmup steps.
        min_lr_ratio (`float`, *optional*, defaults to 0):
            The final learning rate at the end of the linear decay will be `init_lr * min_lr_ratio`.
        adam_beta1 (`float`, *optional*, defaults to 0.9):
            The beta1 to use in Adam.
        adam_beta2 (`float`, *optional*, defaults to 0.999):
            The beta2 to use in Adam.
        adam_epsilon (`float`, *optional*, defaults to 1e-8):
            The epsilon to use in Adam.
        adam_clipnorm (`float`, *optional*, defaults to `None`):
            If not `None`, clip the gradient norm for each weight tensor to this value.
        adam_global_clipnorm (`float`, *optional*, defaults to `None`)
            If not `None`, clip gradient norm to this value. When using this argument, the norm is computed over all
            weight tensors, as if they were concatenated into a single vector.
        weight_decay_rate (`float`, *optional*, defaults to 0):
            The weight decay to use.
        power (`float`, *optional*, defaults to 1.0):
            The power to use for PolynomialDecay.
        include_in_weight_decay (`List[str]`, *optional*):
            List of the parameter names (or re patterns) to apply weight decay to. If none is passed, weight decay is
            applied to all parameters except bias and layer norm parameters.
    )r
   Zdecay_stepsZend_learning_rater   )r
   r   r   r+   Z	LayerNormZ
layer_normZbias)	learning_rater8   beta_1beta_2epsilonclipnormglobal_clipnormexclude_from_weight_decayr9   )r:   r;   r<   r=   r>   r?   )r   keras
optimizers	schedulesZPolynomialDecayr   AdamWeightDecayr   )r/   r0   r1   r2   r3   r4   r5   r6   r7   r8   r   r9   Zlr_scheduleZ	optimizerr   r   r   create_optimizerX   sB    .

rE   c                       s   e Zd ZdZdeeejjj	j
f eeeeeeee  eee  ed		 fd
dZe fddZ fddZdd Zd fdd	Zdd Zd  fdd	Zd! fdd	Z fddZdd Z  ZS )"rD   at
  
    Adam enables L2 weight decay and clip_by_global_norm on gradients. Just adding the square of the weights to the
    loss function is *not* the correct way of using L2 regularization/weight decay with Adam, since that will interact
    with the m and v parameters in strange ways as shown in [Decoupled Weight Decay
    Regularization](https://arxiv.org/abs/1711.05101).

    Instead we want to decay the weights in a manner that doesn't interact with the m/v parameters. This is equivalent
    to adding the square of the weights to the loss with plain (non-momentum) SGD.

    Args:
        learning_rate (`Union[float, tf.keras.optimizers.schedules.LearningRateSchedule]`, *optional*, defaults to 1e-3):
            The learning rate to use or a schedule.
        beta_1 (`float`, *optional*, defaults to 0.9):
            The beta1 parameter in Adam, which is the exponential decay rate for the 1st momentum estimates.
        beta_2 (`float`, *optional*, defaults to 0.999):
            The beta2 parameter in Adam, which is the exponential decay rate for the 2nd momentum estimates.
        epsilon (`float`, *optional*, defaults to 1e-7):
            The epsilon parameter in Adam, which is a small constant for numerical stability.
        amsgrad (`bool`, *optional*, default to `False`):
            Whether to apply AMSGrad variant of this algorithm or not, see [On the Convergence of Adam and
            Beyond](https://arxiv.org/abs/1904.09237).
        weight_decay_rate (`float`, *optional*, defaults to 0):
            The weight decay to apply.
        include_in_weight_decay (`List[str]`, *optional*):
            List of the parameter names (or re patterns) to apply weight decay to. If none is passed, weight decay is
            applied to all parameters by default (unless they are in `exclude_from_weight_decay`).
        exclude_from_weight_decay (`List[str]`, *optional*):
            List of the parameter names (or re patterns) to exclude from applying weight decay to. If a
            `include_in_weight_decay` is passed, the names in it will supersede this list.
        name (`str`, *optional*, defaults to 'AdamWeightDecay'):
            Optional name for the operations created when applying gradients.
        kwargs (`Dict[str, Any]`, *optional*):
            Keyword arguments. Allowed to be {`clipnorm`, `clipvalue`, `lr`, `decay`}. `clipnorm` is clip gradients by
            norm; `clipvalue` is clip gradients by value, `decay` is included for backward compatibility to allow time
            inverse decay of learning rate. `lr` is included for backward compatibility, recommended to use
            `learning_rate` instead.
    MbP?r,   r-   Hz>Fr+   N)	r:   r;   r<   r=   amsgradr8   r9   r@   r   c
                    s0   t  j||||||	f|
 || _|| _|| _d S r   )r   r   r8   _include_in_weight_decay_exclude_from_weight_decay)r   r:   r;   r<   r=   rH   r8   r9   r@   r   kwargsr   r   r   r      s    zAdamWeightDecay.__init__c                    s   dt i}tt| j||dS )z?Creates an optimizer from its config with WarmUp custom object.r   )custom_objects)r   r   rD   from_config)clsconfigrL   r   r   r   rM      s    zAdamWeightDecay.from_configc                    s4   t t| ||| tj| jdd|||f d< d S )NZadam_weight_decay_rater   r8   )r   rD   _prepare_localr   constantr8   )r   
var_device	var_dtypeapply_stater   r   r   rP      s
     zAdamWeightDecay._prepare_localc                 C   sB   |  |j}|r:|j|| ||j|jjf d  | jdS t S )Nr8   )Zuse_locking)	_do_use_weight_decayr   Z
assign_subdevicedtype
base_dtypeZ_use_lockingr   Zno_op)r   varr:   rT   Zdo_decayr   r   r   _decay_weights_op   s    z!AdamWeightDecay._decay_weights_opc                    s2   t t| \}}tt| jt||fd|i|S )Nr   )listzipr   rD   apply_gradients)r   Zgrads_and_varsr   rK   Zgradstvarsr   r   r   r]      s    zAdamWeightDecay.apply_gradientsc                 C   s\   |dkr| j | i fS |pi }|||f}|dkrL| ||}||||f< |d d|ifS )z1Retrieves the learning rate with the given state.Nlr_trT   )Z_decayed_lr_tgetZ_fallback_apply_state)r   rR   rS   rT   Zcoefficientsr   r   r   _get_lr   s    zAdamWeightDecay._get_lrc              
      s`   |  |j|jj|\}}| |||}t|g$ tt| j	||f|W  5 Q R  S Q R X d S r   )
ra   rV   rW   rX   rZ   r   control_dependenciesr   rD   _resource_apply_dense)r   gradrY   rT   r_   rK   decayr   r   r   rc     s    z%AdamWeightDecay._resource_apply_densec              
      sb   |  |j|jj|\}}| |||}t|g& tt| j	|||f|W  5 Q R  S Q R X d S r   )
ra   rV   rW   rX   rZ   r   rb   r   rD   _resource_apply_sparse)r   rd   rY   indicesrT   r_   rK   re   r   r   r   rf     s    z&AdamWeightDecay._resource_apply_sparsec                    s   t   }|d| ji |S )Nr8   )r   r"   updater8   )r   rO   r   r   r   r"     s    
zAdamWeightDecay.get_configc                 C   sb   | j dkrdS | jr6| jD ]}t||dk	r dS q| jr^| jD ]}t||dk	rB dS qBdS )z0Whether to use L2 weight decay for `param_name`.r   FNT)r8   rI   researchrJ   )r   
param_namerr   r   r   rU     s    


z$AdamWeightDecay._do_use_weight_decay)	rF   r,   r-   rG   Fr+   NNrD   )N)N)N)r#   r$   r%   r&   r   r'   r   rA   rB   rC   LearningRateScheduleboolr   r   r)   r   classmethodrM   rP   rZ   r]   ra   rc   rf   r"   rU   r*   r   r   r   r   rD      s>   (         

	rD   c                   @   s@   e Zd ZdZdd Zedd Zedd Zdd	 Zd
d Z	dS )GradientAccumulatoraR  
    Gradient accumulation utility. When used with a distribution strategy, the accumulator should be called in a
    replica context. Gradients will be accumulated locally on each replica and without synchronization. Users should
    then call `.gradients`, scale the gradients if required, and pass the result to `apply_gradients`.
    c                 C   s   g | _ d| _dS )zInitializes the accumulator.N)
_gradients_accum_stepsr!   r   r   r   r   9  s    zGradientAccumulator.__init__c                 C   s<   | j dkr2tjtjdtjddtjjtjjd| _ | j 	 S )zNumber of accumulated steps.Nr   )rW   FZ	trainableZsynchronizationZaggregation)
rr   r   VariablerQ   Zint64VariableSynchronizationON_READVariableAggregationONLY_FIRST_REPLICAvaluer!   r   r   r   r   >  s    
zGradientAccumulator.stepc                 C   s   | j stddd | j D S )z1The accumulated gradients on the current replica.zBThe accumulator should be called first to initialize the gradientsc                 S   s    g | ]}|d k	r|  n|qS r   )ry   .0gradientr   r   r   
<listcomp>P  s     z1GradientAccumulator.gradients.<locals>.<listcomp>)rq   
ValueErrorr!   r   r   r   	gradientsK  s    zGradientAccumulator.gradientsc                 C   s   | j s"| j}| j dd |D  t|t| j krRtdt| j  dt| t| j |D ]"\}}|dk	r^|dk	r^|| q^| jd dS )z/Accumulates `gradients` on the current replica.c                 S   s8   g | ]0}|d k	r0t jt |dt jjt jjdn|qS )NFrs   )r   rt   
zeros_likeru   rv   rw   rx   rz   r   r   r   r}   W  s   	z0GradientAccumulator.__call__.<locals>.<listcomp>z	Expected z gradients, but got N   )rq   r   extendlenr~   r\   Z
assign_addrr   )r   r   _Zaccum_gradientr|   r   r   r   r    R  s    	zGradientAccumulator.__call__c                 C   s>   | j s
dS | jd | j D ]}|dk	r|t| qdS )z8Resets the accumulated gradients on the current replica.Nr   )rq   rr   Zassignr   r   )r   r|   r   r   r   resetl  s    
zGradientAccumulator.resetN)
r#   r$   r%   r&   r   propertyr   r   r    r   r   r   r   r   rp   .  s   


rp   )	r+   r,   r-   r.   NNr+   r   N)r&   ri   typingr   r   r   r   Z
tensorflowr   Z"tensorflow.keras.optimizers.legacyr   ImportErrorZtensorflow.keras.optimizersrA   rB   rC   rm   r   r'   r(   r)   rE   rD   objectrp   r   r   r   r   <module>   sD   >         
T 