Transformers documentation

Processors

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Processors

Processors can mean two different things in the Transformers library:

  • the objects that pre-process inputs for multi-modal models such as Wav2Vec2 (speech and text) or CLIP (text and vision)
  • deprecated objects that were used in older versions of the library to preprocess data for GLUE or SQUAD.

Multi-modal processors

Any multi-modal model will require an object to encode or decode the data that groups several modalities (among text, vision and audio). This is handled by objects called processors, which group together two or more processing objects such as tokenizers (for the text modality), image processors (for vision) and feature extractors (for audio).

Those processors inherit from the following base class that implements the saving and loading functionality:

class transformers.ProcessorMixin

< >

( *args **kwargs )

This is a mixin used to provide saving/loading functionality for all processor classes.

apply_chat_template

< >

( conversation: list[dict[str, str]] | list[list[dict[str, str]]] chat_template: str | None = None **kwargs: typing_extensions.Unpack[transformers.processing_utils.AllKwargsForChatTemplate] )

Parameters

  • conversation (Union[list[Dict, [str, str]], list[list[dict[str, str]]]]) — The conversation to format.
  • chat_template (Optional[str], optional) — The Jinja template to use for formatting the conversation. If not provided, the tokenizer’s chat template is used.

Similar to the apply_chat_template method on tokenizers, this method applies a Jinja template to input conversations to turn them into a single tokenizable string.

The input is expected to be in the following format, where each message content is a list consisting of text and optionally image or video inputs. One can also provide an image, video, URL or local path which will be used to form pixel_values when return_dict=True. If not provided, one will get only the formatted text, optionally tokenized text.

conversation = [ { “role”: “user”, “content”: [ {“type”: “image”, “url”: “https://www.ilankelman.org/stopsigns/australia.jpg”}, {“type”: “text”, “text”: “Please describe this image in detail.”}, ], }, ]

batch_decode

< >

( *args **kwargs )

This method forwards all its arguments to PreTrainedTokenizer’s batch_decode(). Please refer to the docstring of this method for more information.

check_argument_for_proper_class

< >

( argument_name argument )

Checks the passed argument’s class against the expected transformers class. In case of an unexpected mismatch between expected and actual class, an error is raise. Otherwise, the proper retrieved class is returned.

decode

< >

( *args **kwargs )

This method forwards all its arguments to PreTrainedTokenizer’s decode(). Please refer to the docstring of this method for more information.

from_args_and_dict

< >

( args processor_dict: dict **kwargs ) ~processing_utils.ProcessingMixin

Parameters

  • processor_dict (dict[str, Any]) — Dictionary that will be used to instantiate the processor object. Such a dictionary can be retrieved from a pretrained checkpoint by leveraging the ~processing_utils.ProcessingMixin.to_dict method.
  • kwargs (dict[str, Any]) — Additional parameters from which to initialize the processor object.

Returns

~processing_utils.ProcessingMixin

The processor object instantiated from those parameters.

Instantiates a type of ~processing_utils.ProcessingMixin from a Python dictionary of parameters.

from_pretrained

< >

( pretrained_model_name_or_path: str | os.PathLike cache_dir: str | os.PathLike | None = None force_download: bool = False local_files_only: bool = False token: str | bool | None = None revision: str = 'main' **kwargs )

Parameters

  • pretrained_model_name_or_path (str or os.PathLike) — This can be either:

    • a string, the model id of a pretrained feature_extractor hosted inside a model repo on huggingface.co.
    • a path to a directory containing a feature extractor file saved using the save_pretrained() method, e.g., ./my_model_directory/.
    • a path or url to a saved feature extractor JSON file, e.g., ./my_model_directory/preprocessor_config.json.
  • **kwargs — Additional keyword arguments passed along to both from_pretrained() and ~tokenization_utils_base.PreTrainedTokenizer.from_pretrained.

Instantiate a processor associated with a pretrained model.

This class method is simply calling the feature extractor from_pretrained(), image processor ImageProcessingMixin and the tokenizer ~tokenization_utils_base.PreTrainedTokenizer.from_pretrained methods. Please refer to the docstrings of the methods above for more information.

get_processor_dict

< >

( pretrained_model_name_or_path: str | os.PathLike **kwargs ) tuple[Dict, Dict]

Parameters

  • pretrained_model_name_or_path (str or os.PathLike) — The identifier of the pre-trained checkpoint from which we want the dictionary of parameters.
  • subfolder (str, optional, defaults to "") — In case the relevant files are located inside a subfolder of the model repo on huggingface.co, you can specify the folder name here.

Returns

tuple[Dict, Dict]

The dictionary(ies) that will be used to instantiate the processor object.

From a pretrained_model_name_or_path, resolve to a dictionary of parameters, to be used for instantiating a processor of type ~processing_utils.ProcessingMixin using from_args_and_dict.

post_process_image_text_to_text

< >

( generated_outputs skip_special_tokens = True **kwargs ) list[str]

Parameters

  • generated_outputs (torch.Tensor or np.ndarray) — The output of the model generate function. The output is expected to be a tensor of shape (batch_size, sequence_length) or (sequence_length,).
  • skip_special_tokens (bool, optional, defaults to True) — Whether or not to remove special tokens in the output. Argument passed to the tokenizer’s decode method.
  • **kwargs — Additional arguments to be passed to the tokenizer’s decode method.

Returns

list[str]

The decoded text.

Post-process the output of a vlm to decode the text.

post_process_multimodal_output

< >

( generated_outputs skip_special_tokens = True generation_mode = None **kwargs ) list[str]

Parameters

  • generated_outputs (torch.Tensor or np.ndarray) — The output of the model generate function. The output is expected to be a tensor of shape (batch_size, sequence_length) or (sequence_length,).
  • skip_special_tokens (bool, optional, defaults to True) — Whether or not to remove special tokens in the output. Argument passed to the tokenizer’s batch_decode method.
  • generation_mode (str, optional) — Generation mode indicated which modality to output and can be one of ["text", "image", "audio"].
  • **kwargs — Additional arguments to be passed to the tokenizer’s batch_decode method.

Returns

list[str]

The decoded text.

Post-process the output of a multimodal model to return the requested modality output. If the model cannot generated the requested modality, an error will be raised.

push_to_hub

< >

( repo_id: str commit_message: str | None = None commit_description: str | None = None private: bool | None = None token: bool | str | None = None revision: str | None = None create_pr: bool = False max_shard_size: int | str | None = '50GB' tags: list[str] | None = None )

Parameters

  • repo_id (str) — The name of the repository you want to push your processor to. It should contain your organization name when pushing to a given organization.
  • commit_message (str, optional) — Message to commit while pushing. Will default to "Upload processor".
  • commit_description (str, optional) — The description of the commit that will be created
  • private (bool, optional) — Whether to make the repo private. If None (default), the repo will be public unless the organization’s default is private. This value is ignored if the repo already exists.
  • token (bool or str, optional) — The token to use as HTTP bearer authorization for remote files. If True (default), will use the token generated when running hf auth login (stored in ~/.huggingface).
  • revision (str, optional) — Branch to push the uploaded files to.
  • create_pr (bool, optional, defaults to False) — Whether or not to create a PR with the uploaded files or directly commit.
  • max_shard_size (int or str, optional, defaults to "50GB") — Only applicable for models. The maximum size for a checkpoint before being sharded. Checkpoints shard will then be each of size lower than this size. If expressed as a string, needs to be digits followed by a unit (like "5MB").
  • tags (list[str], optional) — List of tags to push on the Hub.

Upload the processor files to the 🤗 Model Hub.

Examples:

from transformers import AutoProcessor

processor = AutoProcessor.from_pretrained("google-bert/bert-base-cased")

# Push the processor to your namespace with the name "my-finetuned-bert".
processor.push_to_hub("my-finetuned-bert")

# Push the processor to an organization with the name "my-finetuned-bert".
processor.push_to_hub("huggingface/my-finetuned-bert")

register_for_auto_class

< >

( auto_class = 'AutoProcessor' )

Parameters

  • auto_class (str or type, optional, defaults to "AutoProcessor") — The auto class to register this new feature extractor with.

Register this class with a given auto class. This should only be used for custom feature extractors as the ones in the library are already mapped with AutoProcessor.

save_pretrained

< >

( save_directory push_to_hub: bool = False **kwargs )

Parameters

  • save_directory (str or os.PathLike) — Directory where the feature extractor JSON file and the tokenizer files will be saved (directory will be created if it does not exist).
  • push_to_hub (bool, optional, defaults to False) — Whether or not to push your model to the Hugging Face model hub after saving it. You can specify the repository you want to push to with repo_id (will default to the name of save_directory in your namespace).
  • kwargs (dict[str, Any], optional) — Additional key word arguments passed along to the push_to_hub() method.

Saves the attributes of this processor (feature extractor, tokenizer…) in the specified directory so that it can be reloaded using the from_pretrained() method.

This class method is simply calling save_pretrained() and save_pretrained(). Please refer to the docstrings of the methods above for more information.

to_dict

< >

( ) dict[str, Any]

Returns

dict[str, Any]

Dictionary of all the attributes that make up this processor instance.

Serializes this instance to a Python dictionary.

to_json_file

< >

( json_file_path: str | os.PathLike )

Parameters

  • json_file_path (str or os.PathLike) — Path to the JSON file in which this processor instance’s parameters will be saved.

Save this instance to a JSON file.

to_json_string

< >

( ) str

Returns

str

String containing all the attributes that make up this feature_extractor instance in JSON format.

Serializes this instance to a JSON string.

Processing kwargs

Processor __call__ methods accept keyword arguments organized by modality. The following TypedDict classes define the available keyword arguments for each modality. Model-specific processors may subclass these to add or override fields.

class transformers.ProcessingKwargs

< >

( )

Base class for kwargs passing to processors. In case a model has specific kwargs that are not present in the base class or default values for existing keys, it should have its own ModelProcessorKwargs class that inherits from ProcessingKwargs to provide: 1) Additional typed keys and that this model requires to process inputs. 2) Default values for existing keys under a _defaults attribute. New keys have to be defined as follows to ensure type hinting is done correctly.

# adding a new image kwarg for this model
class ModelImagesKwargs(ImagesKwargs, total=False):
    new_image_kwarg: Optional[bool]

class ModelProcessorKwargs(ProcessingKwargs, total=False):
    images_kwargs: ModelImagesKwargs
    _defaults = {
        "images_kwargs: {
            "new_image_kwarg": False,
        }
        "text_kwargs": {
            "padding": "max_length",
        },
    }

For Python 3.8 compatibility, when inheriting from this class and overriding one of the kwargs,

you need to manually update the annotations dictionary. This can be done as follows:

class CustomProcessorKwargs(ProcessingKwargs, total=False):
    images_kwargs: CustomImagesKwargs

CustomProcessorKwargs.__annotations__["images_kwargs"] = CustomImagesKwargs  # python 3.8 compatibility

class transformers.TextKwargs

< >

( )

Parameters

  • add_special_tokens (bool, optional) — Whether or not to add special tokens when encoding the sequences.
  • padding (bool, str or PaddingStrategy, optional) — Activates and controls padding.
  • truncation (bool, str or TruncationStrategy, optional) — Activates and controls truncation.
  • max_length (int, optional) — Controls the maximum length to use by one of the truncation/padding parameters.
  • stride (int, optional) — If set, the overflowing tokens will contain some tokens from the end of the truncated sequence.
  • is_split_into_words (bool, optional) — Whether or not the input is already pre-tokenized.
  • pad_to_multiple_of (int, optional) — If set, will pad the sequence to a multiple of the provided value.
  • return_token_type_ids (bool, optional) — Whether to return token type IDs.
  • return_attention_mask (bool, optional) — Whether to return the attention mask.
  • return_overflowing_tokens (bool, optional) — Whether or not to return overflowing token sequences.
  • return_special_tokens_mask (bool, optional) — Whether or not to return special tokens mask information.
  • return_offsets_mapping (bool, optional) — Whether or not to return (char_start, char_end) for each token.
  • return_length (bool, optional) — Whether or not to return the lengths of the encoded inputs.
  • verbose (bool, optional) — Whether or not to print more information and warnings.
  • padding_side (str, optional) — The side on which padding will be applied.
  • return_mm_token_type_ids (bool, optional) — Whether to return multimodal token type ids indicating mm placeholder token positions.
  • return_tensors (str or TensorType, optional) — If set, will return tensors of a particular framework. Acceptable values are:
    • 'pt': Return PyTorch torch.Tensor objects.
    • 'np': Return NumPy np.ndarray objects.

Keyword arguments for text processing. For extended documentation, check out tokenization_utils_base methods and docstrings associated.

class transformers.ImagesKwargs

< >

( )

Parameters

  • do_convert_rgb (bool) — Whether to convert the image to RGB format.
  • do_resize (bool, optional) — Whether to resize the image.
  • size (dict[str, int], optional) — Resize the shorter side of the input to size["shortest_edge"].
  • crop_size (dict[str, int], optional) — Desired output size when applying center-cropping.
  • resample (PILImageResampling, optional) — Resampling filter to use if resizing the image.
  • do_rescale (bool, optional) — Whether to rescale the image by the specified scale rescale_factor.
  • rescale_factor (int or float, optional) — Scale factor to use if rescaling the image.
  • do_normalize (bool, optional) — Whether to normalize the image.
  • image_mean (float or list[float] or tuple[float, float, float], optional) — Mean to use if normalizing the image.
  • image_std (float or list[float] or tuple[float, float, float], optional) — Standard deviation to use if normalizing the image.
  • do_pad (bool, optional) — Whether to pad the images in the batch.
  • pad_size (dict[str, int], optional) — The size {"height": int, "width" int} to pad the images to.
  • do_center_crop (bool, optional) — Whether to center crop the image.
  • data_format (ChannelDimension or str, optional) — The channel dimension format for the output image.
  • input_data_format (ChannelDimension or str, optional) — The channel dimension format for the input image.
  • device (Union[str, torch.Tensor], optional) — The device to use for processing (e.g. “cpu”, “cuda”), only relevant for fast image processing.
  • return_tensors (str or TensorType, optional) — If set, will return tensors of a particular framework. Acceptable values are:
    • 'pt': Return PyTorch torch.Tensor objects.
    • 'np': Return NumPy np.ndarray objects.
  • disable_grouping (bool, optional) — Whether to group images by shapes when processing or not, only relevant for fast image processing.
  • image_seq_length (int, optional) — The number of image tokens to be used for each image in the input. Added for backward compatibility but this should be set as a processor attribute in future models.

Keyword arguments for image processing. For extended documentation, check the appropriate ImageProcessor class methods and docstrings.

class transformers.VideosKwargs

< >

( )

Parameters

  • do_convert_rgb (bool) — Whether to convert the video to RGB format.
  • do_resize (bool) — Whether to resize the video.
  • size (dict[str, int], optional) — Resize the shorter side of the input to size["shortest_edge"].
  • default_to_square (bool, optional, defaults to self.default_to_square) — Whether to default to a square when resizing, if size is an int.
  • resample (PILImageResampling, optional) — Resampling filter to use if resizing the video.
  • do_rescale (bool, optional) — Whether to rescale the video by the specified scale rescale_factor.
  • rescale_factor (int or float, optional) — Scale factor to use if rescaling the video.
  • do_normalize (bool, optional) — Whether to normalize the video.
  • image_mean (float or list[float] or tuple[float, float, float], optional) — Mean to use if normalizing the video.
  • image_std (float or list[float] or tuple[float, float, float], optional) — Standard deviation to use if normalizing the video.
  • do_center_crop (bool, optional) — Whether to center crop the video.
  • do_pad (bool, optional) — Whether to pad the images in the batch.
  • do_sample_frames (bool, optional) — Whether to sample frames from the video before processing or to process the whole video.
  • video_metadata (Union[VideoMetadata, dict], optional) — Metadata of the video containing information about total duration, fps and total number of frames.
  • num_frames (int, optional) — Maximum number of frames to sample when do_sample_frames=True.
  • fps (int or float, optional) — Target frames to sample per second when do_sample_frames=True.
  • crop_size (dict[str, int], optional) — Desired output size when applying center-cropping.
  • data_format (ChannelDimension or str, optional) — The channel dimension format for the output video.
  • input_data_format (ChannelDimension or str, optional) — The channel dimension format for the input video.
  • device (Union[str, torch.Tensor], optional) — The device to use for processing (e.g. “cpu”, “cuda”), only relevant for fast image processing.
  • return_metadata (bool, optional) — Whether to return video metadata or not.
  • return_tensors (str or TensorType, optional) — If set, will return tensors of a particular framework. Acceptable values are:
    • 'pt': Return PyTorch torch.Tensor objects.
    • 'np': Return NumPy np.ndarray objects.

Keyword arguments for video processing.

class transformers.AudioKwargs

< >

( )

Parameters

  • sampling_rate (int, optional) — The sampling rate at which the raw_speech input was sampled.
  • raw_speech (np.ndarray, list[float], list[np.ndarray], list[list[float]]) — The sequence or batch of sequences to be padded. Each sequence can be a numpy array, a list of float values, a list of numpy arrays or a list of list of float values. Must be mono channel audio, not stereo, i.e. single float per timestep.
  • padding (bool, str or PaddingStrategy, optional) — Select a strategy to pad the returned sequences (according to the model’s padding side and padding index) among:

    • True or 'longest': Pad to the longest sequence in the batch (or no padding if only a single sequence if provided).
    • 'max_length': Pad to a maximum length specified with the argument max_length or to the maximum acceptable input length for the model if that argument is not provided.
    • False or 'do_not_pad'
  • max_length (int, optional) — Maximum length of the returned list and optionally padding length (see above).
  • truncation (bool, optional) — Activates truncation to cut input sequences longer than max_length to max_length.
  • pad_to_multiple_of (int, optional) — If set, will pad the sequence to a multiple of the provided value.
  • return_attention_mask (bool, optional) — Whether or not call() should return attention_mask.
  • return_tensors (str or TensorType, optional) — If set, will return tensors of a particular framework. Acceptable values are:

    • 'pt': Return PyTorch torch.Tensor objects.
    • 'np': Return NumPy np.ndarray objects.

Keyword arguments for audio processing.

Deprecated processors

All processors follow the same architecture which is that of the DataProcessor. The processor returns a list of InputExample. These InputExample can be converted to InputFeatures in order to be fed to the model.

class transformers.DataProcessor

< >

( )

Base class for data converters for sequence classification data sets.

get_dev_examples

< >

( data_dir )

Gets a collection of InputExample for the dev set.

get_example_from_tensor_dict

< >

( tensor_dict )

Parameters

  • tensor_dict — Keys and values should match the corresponding Glue tensorflow_dataset examples.

Gets an example from a dict.

get_labels

< >

( )

Gets the list of labels for this data set.

get_test_examples

< >

( data_dir )

Gets a collection of InputExample for the test set.

get_train_examples

< >

( data_dir )

Gets a collection of InputExample for the train set.

tfds_map

< >

( example )

Some tensorflow_datasets datasets are not formatted the same way the GLUE datasets are. This method converts examples to the correct format.

class transformers.InputExample

< >

( guid: str text_a: str text_b: str | None = None label: str | None = None )

Parameters

  • guid — Unique id for the example.
  • text_a — string. The untokenized text of the first sequence. For single sequence tasks, only this sequence must be specified.
  • text_b — (Optional) string. The untokenized text of the second sequence. Only must be specified for sequence pair tasks.
  • label — (Optional) string. The label of the example. This should be specified for train and dev examples, but not for test examples.

A single training/test example for simple sequence classification.

to_json_string

< >

( )

Serializes this instance to a JSON string.

class transformers.InputFeatures

< >

( input_ids: list attention_mask: list[int] | None = None token_type_ids: list[int] | None = None label: int | float | None = None )

Parameters

  • input_ids — Indices of input sequence tokens in the vocabulary.
  • attention_mask — Mask to avoid performing attention on padding token indices. Mask values selected in [0, 1]: Usually 1 for tokens that are NOT MASKED, 0 for MASKED (padded) tokens.
  • token_type_ids — (Optional) Segment token indices to indicate first and second portions of the inputs. Only some models use them.
  • label — (Optional) Label corresponding to the input. Int for classification problems, float for regression problems.

A single set of features of data. Property names are the same names as the corresponding inputs to a model.

to_json_string

< >

( )

Serializes this instance to a JSON string.

GLUE

General Language Understanding Evaluation (GLUE) is a benchmark that evaluates the performance of models across a diverse set of existing NLU tasks. It was released together with the paper GLUE: A multi-task benchmark and analysis platform for natural language understanding

This library hosts a total of 10 processors for the following tasks: MRPC, MNLI, MNLI (mismatched), CoLA, SST2, STSB, QQP, QNLI, RTE and WNLI.

Those processors are:

  • ~data.processors.utils.MrpcProcessor
  • ~data.processors.utils.MnliProcessor
  • ~data.processors.utils.MnliMismatchedProcessor
  • ~data.processors.utils.Sst2Processor
  • ~data.processors.utils.StsbProcessor
  • ~data.processors.utils.QqpProcessor
  • ~data.processors.utils.QnliProcessor
  • ~data.processors.utils.RteProcessor
  • ~data.processors.utils.WnliProcessor

Additionally, the following method can be used to load values from a data file and convert them to a list of InputExample.

transformers.glue_convert_examples_to_features

< >

( examples: list tokenizer: PythonBackend max_length: int | None = None task = None label_list = None output_mode = None )

Parameters

  • examples — List of InputExamples containing the examples.
  • tokenizer — Instance of a tokenizer that will tokenize the examples
  • max_length — Maximum example length. Defaults to the tokenizer’s max_len
  • task — GLUE task
  • label_list — List of labels. Can be obtained from the processor using the processor.get_labels() method
  • output_mode — String indicating the output mode. Either regression or classification

Loads a data file into a list of InputFeatures

XNLI

The Cross-Lingual NLI Corpus (XNLI) is a benchmark that evaluates the quality of cross-lingual text representations. XNLI is crowd-sourced dataset based on MultiNLI: pairs of text are labeled with textual entailment annotations for 15 different languages (including both high-resource language such as English and low-resource languages such as Swahili).

It was released together with the paper XNLI: Evaluating Cross-lingual Sentence Representations

This library hosts the processor to load the XNLI data:

  • ~data.processors.utils.XnliProcessor

Please note that since the gold labels are available on the test set, evaluation is performed on the test set.

An example using these processors is given in the run_xnli.py script.

SQuAD

The Stanford Question Answering Dataset (SQuAD) is a benchmark that evaluates the performance of models on question answering. Two versions are available, v1.1 and v2.0. The first version (v1.1) was released together with the paper SQuAD: 100,000+ Questions for Machine Comprehension of Text. The second version (v2.0) was released alongside the paper Know What You Don’t Know: Unanswerable Questions for SQuAD.

This library hosts a processor for each of the two versions:

Processors

Those processors are:

  • ~data.processors.utils.SquadV1Processor
  • ~data.processors.utils.SquadV2Processor

They both inherit from the abstract class ~data.processors.utils.SquadProcessor

class transformers.data.processors.squad.SquadProcessor

< >

( )

Processor for the SQuAD data set. overridden by SquadV1Processor and SquadV2Processor, used by the version 1.1 and version 2.0 of SQuAD, respectively.

get_dev_examples

< >

( data_dir filename = None )

Parameters

  • data_dir — Directory containing the data files used for training and evaluating.
  • filename — None by default, specify this if the evaluation file has a different name than the original one which is dev-v1.1.json and dev-v2.0.json for squad versions 1.1 and 2.0 respectively.

Returns the evaluation example from the data directory.

get_examples_from_dataset

< >

( dataset evaluate = False )

Parameters

  • dataset — The tfds dataset loaded from tensorflow_datasets.load(“squad”)
  • evaluate — Boolean specifying if in evaluation mode or in training mode

Creates a list of SquadExample using a TFDS dataset.

Examples:

>>> import tensorflow_datasets as tfds

>>> dataset = tfds.load("squad")

>>> training_examples = get_examples_from_dataset(dataset, evaluate=False)
>>> evaluation_examples = get_examples_from_dataset(dataset, evaluate=True)

get_train_examples

< >

( data_dir filename = None )

Parameters

  • data_dir — Directory containing the data files used for training and evaluating.
  • filename — None by default, specify this if the training file has a different name than the original one which is train-v1.1.json and train-v2.0.json for squad versions 1.1 and 2.0 respectively.

Returns the training examples from the data directory.

Additionally, the following method can be used to convert SQuAD examples into ~data.processors.utils.SquadFeatures that can be used as model inputs.

transformers.squad_convert_examples_to_features

< >

( examples tokenizer max_seq_length doc_stride max_query_length is_training padding_strategy = 'max_length' return_dataset = False threads = 1 tqdm_enabled = True )

Parameters

  • examples — list of SquadExample
  • tokenizer — an instance of a child of PreTrainedTokenizer
  • max_seq_length — The maximum sequence length of the inputs.
  • doc_stride — The stride used when the context is too large and is split across several features.
  • max_query_length — The maximum length of the query.
  • is_training — whether to create features for model evaluation or model training.
  • padding_strategy — Default to “max_length”. Which padding strategy to use
  • return_dataset — Default False. Can also be ‘pt’. if ‘pt’: returns a torch.data.TensorDataset.
  • threads — multiple processing threads.

Converts a list of examples into a list of features that can be directly given as input to a model. It is model-dependant and takes advantage of many of the tokenizer’s features to create the model’s inputs.

Example:

processor = SquadV2Processor()
examples = processor.get_dev_examples(data_dir)

features = squad_convert_examples_to_features(
    examples=examples,
    tokenizer=tokenizer,
    max_seq_length=args.max_seq_length,
    doc_stride=args.doc_stride,
    max_query_length=args.max_query_length,
    is_training=not evaluate,
)

These processors as well as the aforementioned method can be used with files containing the data as well as with the tensorflow_datasets package. Examples are given below.

Example usage

Here is an example using the processors as well as the conversion method using data files:

# Loading a V2 processor
processor = SquadV2Processor()
examples = processor.get_dev_examples(squad_v2_data_dir)

# Loading a V1 processor
processor = SquadV1Processor()
examples = processor.get_dev_examples(squad_v1_data_dir)

features = squad_convert_examples_to_features(
    examples=examples,
    tokenizer=tokenizer,
    max_seq_length=max_seq_length,
    doc_stride=args.doc_stride,
    max_query_length=max_query_length,
    is_training=not evaluate,
)

Using tensorflow_datasets is as easy as using a data file:

# tensorflow_datasets only handle Squad V1.
tfds_examples = tfds.load("squad")
examples = SquadV1Processor().get_examples_from_dataset(tfds_examples, evaluate=evaluate)

features = squad_convert_examples_to_features(
    examples=examples,
    tokenizer=tokenizer,
    max_seq_length=max_seq_length,
    doc_stride=args.doc_stride,
    max_query_length=max_query_length,
    is_training=not evaluate,
)

Another example using these processors is given in the run_squad.py script.

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