spaCy/website/docs/api/language.md
2019-02-17 22:25:42 +01:00

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---
title: Language
teaser: A text-processing pipeline
tag: class
source: spacy/language.py
---
Usually you'll load this once per process as `nlp` and pass the instance around
your application. The `Language` class is created when you call
[`spacy.load()`](/api/top-level#spacy.load) and contains the shared vocabulary
and [language data](/usage/adding-languages), optional model data loaded from a
[model package](/models) or a path, and a
[processing pipeline](/usage/processing-pipelines) containing components like
the tagger or parser that are called on a document in order. You can also add
your own processing pipeline components that take a `Doc` object, modify it and
return it.
## Language.\_\_init\_\_ {#init tag="method"}
Initialize a `Language` object.
> #### Example
>
> ```python
> from spacy.vocab import Vocab
> from spacy.language import Language
> nlp = Language(Vocab())
>
> from spacy.lang.en import English
> nlp = English()
> ```
| Name | Type | Description |
| ----------- | ---------- | ------------------------------------------------------------------------------------------ |
| `vocab` | `Vocab` | A `Vocab` object. If `True`, a vocab is created via `Language.Defaults.create_vocab`. |
| `make_doc` | callable | A function that takes text and returns a `Doc` object. Usually a `Tokenizer`. |
| `meta` | dict | Custom meta data for the `Language` class. Is written to by models to add model meta data. |
| **RETURNS** | `Language` | The newly constructed object. |
## Language.\_\_call\_\_ {#call tag="method"}
Apply the pipeline to some text. The text can span multiple sentences, and can
contain arbitrary whitespace. Alignment into the original string is preserved.
> #### Example
>
> ```python
> doc = nlp(u"An example sentence. Another sentence.")
> assert (doc[0].text, doc[0].head.tag_) == ("An", "NN")
> ```
| Name | Type | Description |
| ----------- | ------- | --------------------------------------------------------------------------------- |
| `text` | unicode | The text to be processed. |
| `disable` | list | Names of pipeline components to [disable](/usage/processing-pipelines#disabling). |
| **RETURNS** | `Doc` | A container for accessing the annotations. |
<Infobox title="Changed in v2.0" variant="warning">
Pipeline components to prevent from being loaded can now be added as a list to
`disable`, instead of specifying one keyword argument per component.
```diff
- doc = nlp(u"I don't want parsed", parse=False)
+ doc = nlp(u"I don't want parsed", disable=["parser"])
```
</Infobox>
## Language.pipe {#pipe tag="method"}
Process texts as a stream, and yield `Doc` objects in order. This is usually
more efficient than processing texts one-by-one.
<Infobox title="Important note for spaCy v2.0.x" variant="danger">
Early versions of spaCy used simple statistical models that could be efficiently
multi-threaded, as we were able to entirely release Python's global interpreter
lock. The multi-threading was controlled using the `n_threads` keyword argument
to the `.pipe` method. This keyword argument is now deprecated as of v2.1.0.
Future versions may introduce a `n_process` argument for parallel inference via
multiprocessing.
</Infobox>
> #### Example
>
> ```python
> texts = [u"One document.", u"...", u"Lots of documents"]
> for doc in nlp.pipe(texts, batch_size=50):
> assert doc.is_parsed
> ```
| Name | Type | Description |
| ------------ | ----- | ---------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `texts` | - | A sequence of unicode objects. |
| `as_tuples` | bool | If set to `True`, inputs should be a sequence of `(text, context)` tuples. Output will then be a sequence of `(doc, context)` tuples. Defaults to `False`. |
| `batch_size` | int | The number of texts to buffer. |
| `disable` | list | Names of pipeline components to [disable](/usage/processing-pipelines#disabling). |
| **YIELDS** | `Doc` | Documents in the order of the original text. |
## Language.update {#update tag="method"}
Update the models in the pipeline.
> #### Example
>
> ```python
> for raw_text, entity_offsets in train_data:
> doc = nlp.make_doc(raw_text)
> gold = GoldParse(doc, entities=entity_offsets)
> nlp.update([doc], [gold], drop=0.5, sgd=optimizer)
> ```
| Name | Type | Description |
| ----------- | -------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `docs` | iterable | A batch of `Doc` objects or unicode. If unicode, a `Doc` object will be created from the text. |
| `golds` | iterable | A batch of `GoldParse` objects or dictionaries. Dictionaries will be used to create [`GoldParse`](/api/goldparse) objects. For the available keys and their usage, see [`GoldParse.__init__`](/api/goldparse#init). |
| `drop` | float | The dropout rate. |
| `sgd` | callable | An optimizer. |
| **RETURNS** | dict | Results from the update. |
## Language.begin_training {#begin_training tag="method"}
Allocate models, pre-process training data and acquire an optimizer.
> #### Example
>
> ```python
> optimizer = nlp.begin_training(gold_tuples)
> ```
| Name | Type | Description |
| ------------- | -------- | ---------------------------- |
| `gold_tuples` | iterable | Gold-standard training data. |
| `**cfg` | - | Config parameters. |
| **RETURNS** | callable | An optimizer. |
## Language.use_params {#use_params tag="contextmanager, method"}
Replace weights of models in the pipeline with those provided in the params
dictionary. Can be used as a context manager, in which case, models go back to
their original weights after the block.
> #### Example
>
> ```python
> with nlp.use_params(optimizer.averages):
> nlp.to_disk("/tmp/checkpoint")
> ```
| Name | Type | Description |
| -------- | ---- | --------------------------------------------- |
| `params` | dict | A dictionary of parameters keyed by model ID. |
| `**cfg` | - | Config parameters. |
## Language.preprocess_gold {#preprocess_gold tag="method"}
Can be called before training to pre-process gold data. By default, it handles
nonprojectivity and adds missing tags to the tag map.
| Name | Type | Description |
| ------------ | -------- | ---------------------------------------- |
| `docs_golds` | iterable | Tuples of `Doc` and `GoldParse` objects. |
| **YIELDS** | tuple | Tuples of `Doc` and `GoldParse` objects. |
## Language.create_pipe {#create_pipe tag="method" new="2"}
Create a pipeline component from a factory.
> #### Example
>
> ```python
> parser = nlp.create_pipe("parser")
> nlp.add_pipe(parser)
> ```
| Name | Type | Description |
| ----------- | -------- | ---------------------------------------------------------------------------------- |
| `name` | unicode | Factory name to look up in [`Language.factories`](/api/language#class-attributes). |
| `config` | dict | Configuration parameters to initialize component. |
| **RETURNS** | callable | The pipeline component. |
## Language.add_pipe {#add_pipe tag="method" new="2"}
Add a component to the processing pipeline. Valid components are callables that
take a `Doc` object, modify it and return it. Only one of `before`, `after`,
`first` or `last` can be set. Default behavior is `last=True`.
> #### Example
>
> ```python
> def component(doc):
> # modify Doc and return it return doc
>
> nlp.add_pipe(component, before="ner")
> nlp.add_pipe(component, name="custom_name", last=True)
> ```
| Name | Type | Description |
| ----------- | -------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| `component` | callable | The pipeline component. |
| `name` | unicode | Name of pipeline component. Overwrites existing `component.name` attribute if available. If no `name` is set and the component exposes no name attribute, `component.__name__` is used. An error is raised if the name already exists in the pipeline. |
| `before` | unicode | Component name to insert component directly before. |
| `after` | unicode | Component name to insert component directly after: |
| `first` | bool | Insert component first / not first in the pipeline. |
| `last` | bool | Insert component last / not last in the pipeline. |
## Language.has_pipe {#has_pipe tag="method" new="2"}
Check whether a component is present in the pipeline. Equivalent to
`name in nlp.pipe_names`.
> #### Example
>
> ```python
> nlp.add_pipe(lambda doc: doc, name="component")
> assert "component" in nlp.pipe_names
> assert nlp.has_pipe("component")
> ```
| Name | Type | Description |
| ----------- | ------- | -------------------------------------------------------- |
| `name` | unicode | Name of the pipeline component to check. |
| **RETURNS** | bool | Whether a component of that name exists in the pipeline. |
## Language.get_pipe {#get_pipe tag="method" new="2"}
Get a pipeline component for a given component name.
> #### Example
>
> ```python
> parser = nlp.get_pipe("parser")
> custom_component = nlp.get_pipe("custom_component")
> ```
| Name | Type | Description |
| ----------- | -------- | -------------------------------------- |
| `name` | unicode | Name of the pipeline component to get. |
| **RETURNS** | callable | The pipeline component. |
## Language.replace_pipe {#replace_pipe tag="method" new="2"}
Replace a component in the pipeline.
> #### Example
>
> ```python
> nlp.replace_pipe("parser", my_custom_parser)
> ```
| Name | Type | Description |
| ----------- | -------- | --------------------------------- |
| `name` | unicode | Name of the component to replace. |
| `component` | callable | The pipeline component to insert. |
## Language.rename_pipe {#rename_pipe tag="method" new="2"}
Rename a component in the pipeline. Useful to create custom names for
pre-defined and pre-loaded components. To change the default name of a component
added to the pipeline, you can also use the `name` argument on
[`add_pipe`](/api/language#add_pipe).
> #### Example
>
> ```python
> nlp.rename_pipe("parser", "spacy_parser")
> ```
| Name | Type | Description |
| ---------- | ------- | -------------------------------- |
| `old_name` | unicode | Name of the component to rename. |
| `new_name` | unicode | New name of the component. |
## Language.remove_pipe {#remove_pipe tag="method" new="2"}
Remove a component from the pipeline. Returns the removed component name and
component function.
> #### Example
>
> ```python
> name, component = nlp.remove_pipe("parser")
> assert name == "parser"
> ```
| Name | Type | Description |
| ----------- | ------- | ----------------------------------------------------- |
| `name` | unicode | Name of the component to remove. |
| **RETURNS** | tuple | A `(name, component)` tuple of the removed component. |
## Language.disable_pipes {#disable_pipes tag="contextmanager, method" new="2"}
Disable one or more pipeline components. If used as a context manager, the
pipeline will be restored to the initial state at the end of the block.
Otherwise, a `DisabledPipes` object is returned, that has a `.restore()` method
you can use to undo your changes.
> #### Example
>
> ```python
> with nlp.disable_pipes('tagger', 'parser'):
> nlp.begin_training()
>
> disabled = nlp.disable_pipes('tagger', 'parser')
> nlp.begin_training()
> disabled.restore()
> ```
| Name | Type | Description |
| ----------- | --------------- | ------------------------------------------------------------------------------------ |
| `*disabled` | unicode | Names of pipeline components to disable. |
| **RETURNS** | `DisabledPipes` | The disabled pipes that can be restored by calling the object's `.restore()` method. |
## Language.to_disk {#to_disk tag="method" new="2"}
Save the current state to a directory. If a model is loaded, this will **include
the model**.
> #### Example
>
> ```python
> nlp.to_disk("/path/to/models")
> ```
| Name | Type | Description |
| --------- | ---------------- | --------------------------------------------------------------------------------------------------------------------- |
| `path` | unicode / `Path` | A path to a directory, which will be created if it doesn't exist. Paths may be either strings or `Path`-like objects. |
| `disable` | list | Names of pipeline components to [disable](/usage/processing-pipelines#disabling) and prevent from being saved. |
## Language.from_disk {#from_disk tag="method" new="2"}
Loads state from a directory. Modifies the object in place and returns it. If
the saved `Language` object contains a model, the model will be loaded. Note
that this method is commonly used via the subclasses like `English` or `German`
to make language-specific functionality like the
[lexical attribute getters](/usage/adding-languages#lex-attrs) available to the
loaded object.
> #### Example
>
> ```python
> from spacy.language import Language
> nlp = Language().from_disk("/path/to/model")
>
> # using language-specific subclass
> from spacy.lang.en import English
> nlp = English().from_disk("/path/to/en_model")
> ```
| Name | Type | Description |
| ----------- | ---------------- | --------------------------------------------------------------------------------- |
| `path` | unicode / `Path` | A path to a directory. Paths may be either strings or `Path`-like objects. |
| `disable` | list | Names of pipeline components to [disable](/usage/processing-pipelines#disabling). |
| **RETURNS** | `Language` | The modified `Language` object. |
<Infobox title="Changed in v2.0" variant="warning">
As of spaCy v2.0, the `save_to_directory` method has been renamed to `to_disk`,
to improve consistency across classes. Pipeline components to prevent from being
loaded can now be added as a list to `disable`, instead of specifying one
keyword argument per component.
```diff
- nlp = spacy.load("en", tagger=False, entity=False)
+ nlp = English().from_disk("/model", disable=["tagger', 'ner"])
```
</Infobox>
## Language.to_bytes {#to_bytes tag="method"}
Serialize the current state to a binary string.
> #### Example
>
> ```python
> nlp_bytes = nlp.to_bytes()
> ```
| Name | Type | Description |
| ----------- | ----- | ------------------------------------------------------------------------------------------------------------------- |
| `disable` | list | Names of pipeline components to [disable](/usage/processing-pipelines#disabling) and prevent from being serialized. |
| **RETURNS** | bytes | The serialized form of the `Language` object. |
## Language.from_bytes {#from_bytes tag="method"}
Load state from a binary string. Note that this method is commonly used via the
subclasses like `English` or `German` to make language-specific functionality
like the [lexical attribute getters](/usage/adding-languages#lex-attrs)
available to the loaded object.
> #### Example
>
> ```python
> from spacy.lang.en import English
> nlp_bytes = nlp.to_bytes()
> nlp2 = English()
> nlp2.from_bytes(nlp_bytes)
> ```
| Name | Type | Description |
| ------------ | ---------- | --------------------------------------------------------------------------------- |
| `bytes_data` | bytes | The data to load from. |
| `disable` | list | Names of pipeline components to [disable](/usage/processing-pipelines#disabling). |
| **RETURNS** | `Language` | The `Language` object. |
<Infobox title="Changed in v2.0" variant="warning">
Pipeline components to prevent from being loaded can now be added as a list to
`disable`, instead of specifying one keyword argument per component.
```diff
- nlp = English().from_bytes(bytes, tagger=False, entity=False)
+ nlp = English().from_bytes(bytes, disable=["tagger", "ner"])
```
</Infobox>
## Attributes {#attributes}
| Name | Type | Description |
| --------------------------------------- | ------------------ | ----------------------------------------------------------------------------------------------- |
| `vocab` | `Vocab` | A container for the lexical types. |
| `tokenizer` | `Tokenizer` | The tokenizer. |
| `make_doc` | `lambda text: Doc` | Create a `Doc` object from unicode text. |
| `pipeline` | list | List of `(name, component)` tuples describing the current processing pipeline, in order. |
| `pipe_names` <Tag variant="new">2</Tag> | list | List of pipeline component names, in order. |
| `meta` | dict | Custom meta data for the Language class. If a model is loaded, contains meta data of the model. |
| `path` <Tag variant="new">2</Tag> | `Path` | Path to the model data directory, if a model is loaded. Otherwise `None`. |
## Class attributes {#class-attributes}
| Name | Type | Description |
| -------------------------------------- | ------- | ----------------------------------------------------------------------------------------------------------------------------------- |
| `Defaults` | class | Settings, data and factory methods for creating the `nlp` object and processing pipeline. |
| `lang` | unicode | Two-letter language ID, i.e. [ISO code](https://en.wikipedia.org/wiki/List_of_ISO_639-1_codes). |
| `factories` <Tag variant="new">2</Tag> | dict | Factories that create pre-defined pipeline components, e.g. the tagger, parser or entity recognizer, keyed by their component name. |