Tagger
A trainable pipeline component to predict part-of-speech tags for any part-of-speech tag set.
In the pre-trained pipelines, the tag schemas vary by language; see the individual model pages for details.
Assigned Attributes
Predictions are assigned to Token.tag
.
Location | Value |
---|---|
Token.tag | The part of speech (hash). int |
Token.tag_ | The part of speech. str |
Config and implementation
The default config is defined by the pipeline component factory and describes
how the component should be configured. You can override its settings via the
config
argument on nlp.add_pipe
or in your
config.cfg
for training. See the
model architectures documentation for details on the
architectures and their arguments and hyperparameters.
Setting | Description |
---|---|
model | A model instance that predicts the tag probabilities. The output vectors should match the number of tags in size, and be normalized as probabilities (all scores between 0 and 1, with the rows summing to 1 ). Defaults to Tagger. Model[List[Doc], List[Floats2d]] |
overwrite v3.2 | Whether existing annotation is overwritten. Defaults to False . bool |
scorer v3.2 | The scoring method. Defaults to Scorer.score_token_attr for the attribute "tag" . Optional[Callable] |
neg_prefix v3.2.1 | The prefix used to specify incorrect tags while training. The tagger will learn not to predict exactly this tag. Defaults to ! . str |
label_smoothing v3.6 | Label smoothing factor. Defaults to 0.0 . float |
explosion/spaCy/master/spacy/pipeline/tagger.pyx
Tagger.__init__ method
Create a new pipeline instance. In your application, you would normally use a
shortcut for this and instantiate the component using its string name and
nlp.add_pipe
.
Name | Description |
---|---|
vocab | The shared vocabulary. Vocab |
model | A model instance that predicts the tag probabilities. The output vectors should match the number of tags in size, and be normalized as probabilities (all scores between 0 and 1, with the rows summing to 1 ). Model[List[Doc], List[Floats2d]] |
name | String name of the component instance. Used to add entries to the losses during training. str |
keyword-only | |
overwrite v3.2 | Whether existing annotation is overwritten. Defaults to False . bool |
scorer v3.2 | The scoring method. Defaults to Scorer.score_token_attr for the attribute "tag" . Optional[Callable] |
Tagger.__call__ method
Apply the pipe to one document. The document is modified in place, and returned.
This usually happens under the hood when the nlp
object is called on a text
and all pipeline components are applied to the Doc
in order. Both
__call__
and pipe
delegate to the
predict
and
set_annotations
methods.
Name | Description |
---|---|
doc | The document to process. Doc |
RETURNS | The processed document. Doc |
Tagger.pipe method
Apply the pipe to a stream of documents. This usually happens under the hood
when the nlp
object is called on a text and all pipeline components are
applied to the Doc
in order. Both __call__
and
pipe
delegate to the predict
and
set_annotations
methods.
Name | Description |
---|---|
stream | A stream of documents. Iterable[Doc] |
keyword-only | |
batch_size | The number of documents to buffer. Defaults to 128 . int |
YIELDS | The processed documents in order. Doc |
Tagger.initialize methodv3.0
Initialize the component for training. get_examples
should be a function that
returns an iterable of Example
objects. At least one example
should be supplied. The data examples are used to initialize the model of
the component and can either be the full training data or a representative
sample. Initialization includes validating the network,
inferring missing shapes and
setting up the label scheme based on the data. This method is typically called
by Language.initialize
and lets you customize
arguments it receives via the
[initialize.components]
block in the
config.
Name | Description |
---|---|
get_examples | Function that returns gold-standard annotations in the form of Example objects. Must contain at least one Example . Callable[[], Iterable[Example]] |
keyword-only | |
nlp | The current nlp object. Defaults to None . Optional[Language] |
labels | The label information to add to the component, as provided by the label_data property after initialization. To generate a reusable JSON file from your data, you should run the init labels command. If no labels are provided, the get_examples callback is used to extract the labels from the data, which may be a lot slower. Optional[Iterable[str]] |
Tagger.predict method
Apply the component’s model to a batch of Doc
objects, without
modifying them.
Name | Description |
---|---|
docs | The documents to predict. Iterable[Doc] |
RETURNS | The model’s prediction for each document. |
Tagger.set_annotations method
Modify a batch of Doc
objects, using pre-computed scores.
Name | Description |
---|---|
docs | The documents to modify. Iterable[Doc] |
scores | The scores to set, produced by Tagger.predict . |
Tagger.update method
Learn from a batch of Example
objects containing the
predictions and gold-standard annotations, and update the component’s model.
Delegates to predict
and
get_loss
.
Name | Description |
---|---|
examples | A batch of Example objects to learn from. Iterable[Example] |
keyword-only | |
drop | The dropout rate. float |
sgd | An optimizer. Will be created via create_optimizer if not set. Optional[Optimizer] |
losses | Optional record of the loss during training. Updated using the component name as the key. Optional[Dict[str, float]] |
RETURNS | The updated losses dictionary. Dict[str, float] |
Tagger.rehearse methodexperimentalv3.0
Perform a “rehearsal” update from a batch of data. Rehearsal updates teach the current model to make predictions similar to an initial model, to try to address the “catastrophic forgetting” problem. This feature is experimental.
Name | Description |
---|---|
examples | A batch of Example objects to learn from. Iterable[Example] |
keyword-only | |
drop | The dropout rate. float |
sgd | An optimizer. Will be created via create_optimizer if not set. Optional[Optimizer] |
losses | Optional record of the loss during training. Updated using the component name as the key. Optional[Dict[str, float]] |
RETURNS | The updated losses dictionary. Dict[str, float] |
Tagger.get_loss method
Find the loss and gradient of loss for the batch of documents and their predicted scores.
Name | Description |
---|---|
examples | The batch of examples. Iterable[Example] |
scores | Scores representing the model’s predictions. |
RETURNS | The loss and the gradient, i.e. (loss, gradient) . Tuple[float, float] |
Tagger.create_optimizer method
Create an optimizer for the pipeline component.
Name | Description |
---|---|
RETURNS | The optimizer. Optimizer |
Tagger.use_params methodcontextmanager
Modify the pipe’s model, to use the given parameter values. At the end of the context, the original parameters are restored.
Name | Description |
---|---|
params | The parameter values to use in the model. dict |
Tagger.add_label method
Add a new label to the pipe. Raises an error if the output dimension is already
set, or if the model has already been fully initialized. Note
that you don’t have to call this method if you provide a representative data
sample to the initialize
method. In this case, all labels
found in the sample will be automatically added to the model, and the output
dimension will be inferred
automatically.
Name | Description |
---|---|
label | The label to add. str |
RETURNS | 0 if the label is already present, otherwise 1 . int |
Tagger.to_disk method
Serialize the pipe to disk.
Name | Description |
---|---|
path | A path to a directory, which will be created if it doesn’t exist. Paths may be either strings or Path -like objects. Union[str,Path] |
keyword-only | |
exclude | String names of serialization fields to exclude. Iterable[str] |
Tagger.from_disk method
Load the pipe from disk. Modifies the object in place and returns it.
Name | Description |
---|---|
path | A path to a directory. Paths may be either strings or Path -like objects. Union[str,Path] |
keyword-only | |
exclude | String names of serialization fields to exclude. Iterable[str] |
RETURNS | The modified Tagger object. Tagger |
Tagger.to_bytes method
Serialize the pipe to a bytestring.
Name | Description |
---|---|
keyword-only | |
exclude | String names of serialization fields to exclude. Iterable[str] |
RETURNS | The serialized form of the Tagger object. bytes |
Tagger.from_bytes method
Load the pipe from a bytestring. Modifies the object in place and returns it.
Name | Description |
---|---|
bytes_data | The data to load from. bytes |
keyword-only | |
exclude | String names of serialization fields to exclude. Iterable[str] |
RETURNS | The Tagger object. Tagger |
Tagger.labels property
The labels currently added to the component.
Name | Description |
---|---|
RETURNS | The labels added to the component. Tuple[str, …] |
Tagger.label_data propertyv3.0
The labels currently added to the component and their internal meta information.
This is the data generated by init labels
and used by
Tagger.initialize
to initialize the model with a
pre-defined label set.
Name | Description |
---|---|
RETURNS | The label data added to the component. Tuple[str, …] |
Serialization fields
During serialization, spaCy will export several data fields used to restore
different aspects of the object. If needed, you can exclude them from
serialization by passing in the string names via the exclude
argument.
Name | Description |
---|---|
vocab | The shared Vocab . |
cfg | The config file. You usually don’t want to exclude this. |
model | The binary model data. You usually don’t want to exclude this. |