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    )annotations)Iterable)Tensornn)SentenceTransformer   )BatchHardTripletLoss$BatchHardTripletLossDistanceFunctionc                  z   ^  \ rS rSr\R
                  S4     SU 4S jjjrS	S jrS
S jr\	SS j5       r
SrU =r$ )BatchAllTripletLoss      c                F   > [         TU ]  5         Xl        X0l        X l        g)a
  
BatchAllTripletLoss takes a batch with (sentence, label) pairs and computes the loss for all possible, valid
triplets, i.e., anchor and positive must have the same label, anchor and negative a different label. The labels
must be integers, with same label indicating sentences from the same class. Your train dataset
must contain at least 2 examples per label class.

Args:
    model: SentenceTransformer model
    distance_metric: Function that returns a distance between
        two embeddings. The class SiameseDistanceMetric contains
        pre-defined metrics that can be used.
    margin: Negative samples should be at least margin further
        apart from the anchor than the positive.

References:
    * Source: https://github.com/NegatioN/OnlineMiningTripletLoss/blob/master/online_triplet_loss/losses.py
    * Paper: In Defense of the Triplet Loss for Person Re-Identification, https://arxiv.org/abs/1703.07737
    * Blog post: https://omoindrot.github.io/triplet-loss

Requirements:
    1. Each sentence must be labeled with a class.
    2. Your dataset must contain at least 2 examples per labels class.

Inputs:
    +------------------+--------+
    | Texts            | Labels |
    +==================+========+
    | single sentences | class  |
    +------------------+--------+

Recommendations:
    - Use ``BatchSamplers.GROUP_BY_LABEL`` (:class:`docs <sentence_transformers.training_args.BatchSamplers>`) to
      ensure that each batch contains 2+ examples per label class.

Relations:
    * :class:`BatchHardTripletLoss` uses only the hardest positive and negative samples, rather than all possible, valid triplets.
    * :class:`BatchHardSoftMarginTripletLoss` uses only the hardest positive and negative samples, rather than all possible, valid triplets.
      Also, it does not require setting a margin.
    * :class:`BatchSemiHardTripletLoss` uses only semi-hard triplets, valid triplets, rather than all possible, valid triplets.

Example:
    ::

        from sentence_transformers import SentenceTransformer, SentenceTransformerTrainer, losses
        from datasets import Dataset

        model = SentenceTransformer("microsoft/mpnet-base")
        # E.g. 0: sports, 1: economy, 2: politics
        train_dataset = Dataset.from_dict({
            "sentence": [
                "He played a great game.",
                "The stock is up 20%",
                "They won 2-1.",
                "The last goal was amazing.",
                "They all voted against the bill.",
            ],
            "label": [0, 1, 0, 0, 2],
        })
        loss = losses.BatchAllTripletLoss(model)

        trainer = SentenceTransformerTrainer(
            model=model,
            train_dataset=train_dataset,
            loss=loss,
        )
        trainer.train()

N)super__init__sentence_embeddertriplet_margindistance_metric)selfmodelr   margin	__class__s       h/var/www/html/shao/venv/lib/python3.13/site-packages/sentence_transformers/losses/BatchAllTripletLoss.pyr   BatchAllTripletLoss.__init__   s#    T 	!&$.    c                R    U R                  US   5      S   nU R                  X#5      $ )Nr   sentence_embedding)r   batch_all_triplet_loss)r   sentence_featureslabelsreps       r   forwardBatchAllTripletLoss.forward\   s/    $$%6q%9:;OP**677r   c                J   U R                  U5      nUR                  S5      nUR                  S5      nXE-
  U R                  -   n[        R                  " U5      nUR                  5       U-  nSXfS:  '   XfS:     nUR                  S5      n	UR                  5       U	S-   -  nU$ )a  Build the triplet loss over a batch of embeddings.
We generate all the valid triplets and average the loss over the positive ones.
Args:
    labels: labels of the batch, of size (batch_size,)
    embeddings: tensor of shape (batch_size, embed_dim)
    margin: margin for triplet loss
    squared: Boolean. If true, output is the pairwise squared euclidean distance matrix.
             If false, output is the pairwise euclidean distance matrix.
Returns:
    Label_Sentence_Triplet: scalar tensor containing the triplet loss
   r   r   gؗҜ<)r   	unsqueezer   r	   get_triplet_maskfloatsizesum)
r   r    
embeddingspairwise_distanchor_positive_distanchor_negative_disttriplet_lossmaskvalid_tripletsnum_positive_tripletss
             r   r   *BatchAllTripletLoss.batch_all_triplet_loss`   s     ,,Z8,66q9,66q9 ,BTEXEXX $44V<zz|l2 *+A%& &U&:; . 3 3A 6
 $'')-BU-JKr   c                    g)Na  
@misc{hermans2017defense,
    title={In Defense of the Triplet Loss for Person Re-Identification},
    author={Alexander Hermans and Lucas Beyer and Bastian Leibe},
    year={2017},
    eprint={1703.07737},
    archivePrefix={arXiv},
    primaryClass={cs.CV}
}
 )r   s    r   citationBatchAllTripletLoss.citation   s    	r   )r   r   r   )r   r   r   r(   returnNone)r   zIterable[dict[str, Tensor]]r    r   r8   r   )r    r   r+   r   r8   r   )r8   str)__name__
__module____qualname____firstlineno__r
   eucledian_distancer   r"   r   propertyr6   __static_attributes____classcell__)r   s   @r   r   r      s\     =OO	M/"M/ 	M/
 
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   Moduler   r5   r   r   <module>rH      s&    " $  I \J")) Jr   