SpanFinder
The span finder identifies potentially overlapping, unlabeled spans. It
identifies tokens that start or end spans and annotates unlabeled spans between
starts and ends, with optional filters for min and max span length. It is
intended for use in combination with a component like
SpanCategorizer
that may further filter or label the
spans. Predicted spans will be saved in a SpanGroup
on the
doc under doc.spans[spans_key]
, where spans_key
is a component config
setting.
Assigned Attributes
Predictions will be saved to Doc.spans[spans_key]
as a
SpanGroup
.
spans_key
defaults to "sc"
, but can be passed as a parameter. The
span_finder
component will overwrite any existing spans under the spans key
doc.spans[spans_key]
.
Location | Value |
---|---|
Doc.spans[spans_key] | The unlabeled spans. SpanGroup |
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 is given a list of documents and predicts a probability for each token. Model[List[Doc],Floats2d] |
spans_key | Key of the Doc.spans dict to save the spans under. During initialization and training, the component will look for spans on the reference document under the same key. Defaults to "sc" . str |
threshold | Minimum probability to consider a prediction positive. Defaults to 0.5 . float |
max_length | Maximum length of the produced spans, defaults to 25 . Optional[int] |
min_length | Minimum length of the produced spans, defaults to None meaning shortest span length is 1. Optional[int] |
scorer | The scoring method. Defaults to Scorer.score_spans for Doc.spans[spans_key] with overlapping spans allowed. Optional[Callable] |
explosion/spaCy/master/spacy/pipeline/span_finder.py
SpanFinder.__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 is given a list of documents and predicts a probability for each token. Model[List[Doc],Floats2d] |
name | String name of the component instance. Used to add entries to the losses during training. str |
keyword-only | |
spans_key | Key of the Doc.spans dict to save the spans under. During initialization and training, the component will look for spans on the reference document under the same key. Defaults to "sc" . str |
threshold | Minimum probability to consider a prediction positive. Defaults to 0.5 . float |
max_length | Maximum length of the produced spans, defaults to None meaning unlimited length. Optional[int] |
min_length | Minimum length of the produced spans, defaults to None meaning shortest span length is 1. Optional[int] |
scorer | The scoring method. Defaults to Scorer.score_spans for Doc.spans[spans_key] with overlapping spans allowed. Optional[Callable] |
SpanFinder.__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 |
SpanFinder.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 |
SpanFinder.initialize method
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 and
inferring missing shapes 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] |
SpanFinder.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. |
SpanFinder.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 SpanFinder.predict . |
SpanFinder.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] |
SpanFinder.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] |
spans_scores | Scores representing the model’s predictions. Tuple[Ragged,Floats2d] |
RETURNS | The loss and the gradient, i.e. (loss, gradient) . Tuple[float,Floats2d] |
SpanFinder.create_optimizer method
Create an optimizer for the pipeline component.
Name | Description |
---|---|
RETURNS | The optimizer. Optimizer |
SpanFinder.use_params methodcontextmanager
Modify the pipe’s model to use the given parameter values.
Name | Description |
---|---|
params | The parameter values to use in the model. dict |
SpanFinder.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] |
SpanFinder.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 SpanFinder object. SpanFinder |
SpanFinder.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 SpanFinder object. bytes |
SpanFinder.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 SpanFinder object. SpanFinder |
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. |