spaCy/website/docs/usage/models.md
2020-08-19 00:28:37 +02:00

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---
title: Models & Languages
next: usage/facts-figures
menu:
- ['Quickstart', 'quickstart']
- ['Language Support', 'languages']
- ['Installation & Usage', 'download']
- ['Production Use', 'production']
---
spaCy's models can be installed as **Python packages**. This means that they're
a component of your application, just like any other module. They're versioned
and can be defined as a dependency in your `requirements.txt`. Models can be
installed from a download URL or a local directory, manually or via
[pip](https://pypi.python.org/pypi/pip). Their data can be located anywhere on
your file system.
> #### Important note
>
> If you're upgrading to spaCy v3.x, you need to **download the new models**. If
> you've trained statistical models that use spaCy's annotations, you should
> **retrain your models** after updating spaCy. If you don't retrain, you may
> suffer train/test skew, which might decrease your accuracy.
## Quickstart {hidden="true"}
import QuickstartModels from 'widgets/quickstart-models.js'
<QuickstartModels title="Quickstart" id="quickstart" description="Install a default model, get the code to load it from within spaCy and an example to test it. For more options, see the section on available models below." />
## Language support {#languages}
spaCy currently provides support for the following languages. You can help by
[improving the existing language data](/usage/adding-languages#language-data)
and extending the tokenization patterns.
[See here](https://github.com/explosion/spaCy/issues/3056) for details on how to
contribute to model development.
> #### Usage note
>
> If a model is available for a language, you can download it using the
> [`spacy download`](/api/cli#download) command. In order to use languages that
> don't yet come with a model, you have to import them directly, or use
> [`spacy.blank`](/api/top-level#spacy.blank):
>
> ```python
> from spacy.lang.fi import Finnish
> nlp = Finnish() # use directly
> nlp = spacy.blank("fi") # blank instance
> ```
>
> If lemmatization rules are available for your language, make sure to install
> spaCy with the `lookups` option, or install
> [`spacy-lookups-data`](https://github.com/explosion/spacy-lookups-data)
> separately in the same environment:
>
> ```bash
> $ pip install spacy[lookups]
> ```
import Languages from 'widgets/languages.js'
<Languages />
### Multi-language support {#multi-language new="2"}
> ```python
> # Standard import
> from spacy.lang.xx import MultiLanguage
> nlp = MultiLanguage()
>
> # With lazy-loading
> nlp = spacy.blank("xx")
> ```
spaCy also supports models trained on more than one language. This is especially
useful for named entity recognition. The language ID used for multi-language or
language-neutral models is `xx`. The language class, a generic subclass
containing only the base language data, can be found in
[`lang/xx`](https://github.com/explosion/spaCy/tree/master/spacy/lang/xx).
To train a model using the neutral multi-language class, you can set
`lang = "xx"` in your [training config](/usage/training#config). You can also
import the `MultiLanguage` class directly, or call
[`spacy.blank("xx")`](/api/top-level#spacy.blank) for lazy-loading.
### Chinese language support {#chinese new=2.3}
The Chinese language class supports three word segmentation options:
> ```python
> from spacy.lang.zh import Chinese
>
> # Character segmentation (default)
> nlp = Chinese()
>
> # Jieba
> cfg = {"segmenter": "jieba"}
> nlp = Chinese(meta={"tokenizer": {"config": cfg}})
>
> # PKUSeg with "default" model provided by pkuseg
> cfg = {"segmenter": "pkuseg", "pkuseg_model": "default"}
> nlp = Chinese(meta={"tokenizer": {"config": cfg}})
> ```
1. **Character segmentation:** Character segmentation is the default
segmentation option. It's enabled when you create a new `Chinese` language
class or call `spacy.blank("zh")`.
2. **Jieba:** `Chinese` uses [Jieba](https://github.com/fxsjy/jieba) for word
segmentation with the tokenizer option `{"segmenter": "jieba"}`.
3. **PKUSeg**: As of spaCy v2.3.0, support for
[PKUSeg](https://github.com/lancopku/PKUSeg-python) has been added to support
better segmentation for Chinese OntoNotes and the provided
[Chinese models](/models/zh). Enable PKUSeg with the tokenizer option
`{"segmenter": "pkuseg"}`.
<Infobox variant="warning">
In spaCy v3.0, the default Chinese word segmenter has switched from Jieba to
character segmentation. Also note that
[`pkuseg`](https://github.com/lancopku/pkuseg-python) doesn't yet ship with
pre-compiled wheels for Python 3.8. If you're running Python 3.8, you can
install it from our fork and compile it locally:
```bash
$ pip install https://github.com/honnibal/pkuseg-python/archive/master.zip
```
</Infobox>
<Accordion title="Details on spaCy's Chinese API">
The `meta` argument of the `Chinese` language class supports the following
following tokenizer config settings:
| Name | Description |
| ------------------ | --------------------------------------------------------------------------------------------------------------- |
| `segmenter` | Word segmenter: `char`, `jieba` or `pkuseg`. Defaults to `char`. ~~str~~ |
| `pkuseg_model` | **Required for `pkuseg`:** Name of a model provided by `pkuseg` or the path to a local model directory. ~~str~~ |
| `pkuseg_user_dict` | Optional path to a file with one word per line which overrides the default `pkuseg` user dictionary. ~~str~~ |
```python
### Examples
# Load "default" model
cfg = {"segmenter": "pkuseg", "pkuseg_model": "default"}
nlp = Chinese(config={"tokenizer": {"config": cfg}})
# Load local model
cfg = {"segmenter": "pkuseg", "pkuseg_model": "/path/to/pkuseg_model"}
nlp = Chinese(config={"tokenizer": {"config": cfg}})
# Override the user directory
cfg = {"segmenter": "pkuseg", "pkuseg_model": "default", "pkuseg_user_dict": "/path"}
nlp = Chinese(config={"tokenizer": {"config": cfg}})
```
You can also modify the user dictionary on-the-fly:
```python
# Append words to user dict
nlp.tokenizer.pkuseg_update_user_dict(["中国", "ABC"])
# Remove all words from user dict and replace with new words
nlp.tokenizer.pkuseg_update_user_dict(["中国"], reset=True)
# Remove all words from user dict
nlp.tokenizer.pkuseg_update_user_dict([], reset=True)
```
</Accordion>
<Accordion title="Details on pretrained and custom Chinese models" spaced>
The [Chinese models](/models/zh) provided by spaCy include a custom `pkuseg`
model trained only on
[Chinese OntoNotes 5.0](https://catalog.ldc.upenn.edu/LDC2013T19), since the
models provided by `pkuseg` include data restricted to research use. For
research use, `pkuseg` provides models for several different domains
(`"default"`, `"news"` `"web"`, `"medicine"`, `"tourism"`) and for other uses,
`pkuseg` provides a simple
[training API](https://github.com/lancopku/pkuseg-python/blob/master/readme/readme_english.md#usage):
```python
import pkuseg
from spacy.lang.zh import Chinese
# Train pkuseg model
pkuseg.train("train.utf8", "test.utf8", "/path/to/pkuseg_model")
# Load pkuseg model in spaCy Chinese tokenizer
nlp = Chinese(meta={"tokenizer": {"config": {"pkuseg_model": "/path/to/pkuseg_model", "require_pkuseg": True}}})
```
</Accordion>
### Japanese language support {#japanese new=2.3}
> ```python
> from spacy.lang.ja import Japanese
>
> # Load SudachiPy with split mode A (default)
> nlp = Japanese()
>
> # Load SudachiPy with split mode B
> cfg = {"split_mode": "B"}
> nlp = Japanese(meta={"tokenizer": {"config": cfg}})
> ```
The Japanese language class uses
[SudachiPy](https://github.com/WorksApplications/SudachiPy) for word
segmentation and part-of-speech tagging. The default Japanese language class and
the provided Japanese models use SudachiPy split mode `A`. The `meta` argument
of the `Japanese` language class can be used to configure the split mode to `A`,
`B` or `C`.
<Infobox variant="warning">
If you run into errors related to `sudachipy`, which is currently under active
development, we suggest downgrading to `sudachipy==0.4.5`, which is the version
used for training the current [Japanese models](/models/ja).
</Infobox>
## Installing and using models {#download}
The easiest way to download a model is via spaCy's
[`download`](/api/cli#download) command. It takes care of finding the
best-matching model compatible with your spaCy installation.
> #### Important note for v3.0
>
> Note that as of spaCy v3.0, model shortcut links that create (potentially
> brittle) symlinks in your spaCy installation are **deprecated**. To download
> and load an installed model, use its full name:
>
> ```diff
> - python -m spacy download en
> + python -m spacy dowmload en_core_web_sm
> ```
>
> ```diff
> - nlp = spacy.load("en")
> + nlp = spacy.load("en_core_web_sm")
> ```
```cli
# Download best-matching version of a model for your spaCy installation
$ python -m spacy download en_core_web_sm
# Download exact model version
$ python -m spacy download en_core_web_sm-3.0.0 --direct
```
The download command will [install the model](/usage/models#download-pip) via
pip and place the package in your `site-packages` directory.
```cli
$ pip install -U spacy
$ python -m spacy download en_core_web_sm
```
```python
import spacy
nlp = spacy.load("en_core_web_sm")
doc = nlp("This is a sentence.")
```
### Installation via pip {#download-pip}
To download a model directly using [pip](https://pypi.python.org/pypi/pip),
point `pip install` to the URL or local path of the archive file. To find the
direct link to a model, head over to the
[model releases](https://github.com/explosion/spacy-models/releases), right
click on the archive link and copy it to your clipboard.
```bash
# With external URL
$ pip install https://github.com/explosion/spacy-models/releases/download/en_core_web_sm-3.0.0/en_core_web_sm-3.0.0.tar.gz
# With local file
$ pip install /Users/you/en_core_web_sm-3.0.0.tar.gz
```
By default, this will install the model into your `site-packages` directory. You
can then use `spacy.load()` to load it via its package name or
[import it](#usage-import) explicitly as a module. If you need to download
models as part of an automated process, we recommend using pip with a direct
link, instead of relying on spaCy's [`download`](/api/cli#download) command.
You can also add the direct download link to your application's
`requirements.txt`. For more details, see the section on
[working with models in production](#production).
### Manual download and installation {#download-manual}
In some cases, you might prefer downloading the data manually, for example to
place it into a custom directory. You can download the model via your browser
from the [latest releases](https://github.com/explosion/spacy-models/releases),
or configure your own download script using the URL of the archive file. The
archive consists of a model directory that contains another directory with the
model data.
```yaml
### Directory structure {highlight="6"}
└── en_core_web_md-3.0.0.tar.gz # downloaded archive
├── setup.py # setup file for pip installation
├── meta.json # copy of model meta
└── en_core_web_md # 📦 model package
├── __init__.py # init for pip installation
└── en_core_web_md-3.0.0 # model data
├── config.cfg # model config
├── meta.json # model meta
└── ... # directories with component data
```
You can place the **model package directory** anywhere on your local file
system.
### Using models with spaCy {#usage}
To load a model, use [`spacy.load`](/api/top-level#spacy.load) with the model's
package name or a path to the data directory:
> #### Important note for v3.0
>
> Note that as of spaCy v3.0, model shortcut links that create (potentially
> brittle) symlinks in your spaCy installation are **deprecated**. To load an
> installed model, use its full name:
>
> ```diff
> - nlp = spacy.load("en")
> + nlp = spacy.load("en_core_web_sm")
> ```
```python
import spacy
nlp = spacy.load("en_core_web_sm") # load model package "en_core_web_sm"
nlp = spacy.load("/path/to/en_core_web_sm") # load package from a directory
doc = nlp("This is a sentence.")
```
<Infobox title="Tip: Preview model info" emoji="💡">
You can use the [`info`](/api/cli#info) command or
[`spacy.info()`](/api/top-level#spacy.info) method to print a model's meta data
before loading it. Each `Language` object with a loaded model also exposes the
model's meta data as the attribute `meta`. For example, `nlp.meta['version']`
will return the model's version.
</Infobox>
### Importing models as modules {#usage-import}
If you've installed a model via spaCy's downloader, or directly via pip, you can
also `import` it and then call its `load()` method with no arguments:
```python
### {executable="true"}
import en_core_web_sm
nlp = en_core_web_sm.load()
doc = nlp("This is a sentence.")
```
How you choose to load your models ultimately depends on personal preference.
However, **for larger code bases**, we usually recommend native imports, as this
will make it easier to integrate models with your existing build process,
continuous integration workflow and testing framework. It'll also prevent you
from ever trying to load a model that is not installed, as your code will raise
an `ImportError` immediately, instead of failing somewhere down the line when
calling `spacy.load()`.
For more details, see the section on
[working with models in production](#production).
### Using your own models {#own-models}
If you've trained your own model, for example for
[additional languages](/usage/adding-languages) or
[custom named entities](/usage/training#ner), you can save its state using the
[`Language.to_disk()`](/api/language#to_disk) method. To make the model more
convenient to deploy, we recommend wrapping it as a Python package.
For more information and a detailed guide on how to package your model, see the
documentation on [saving and loading models](/usage/saving-loading#models).
## Using models in production {#production}
If your application depends on one or more models, you'll usually want to
integrate them into your continuous integration workflow and build process.
While spaCy provides a range of useful helpers for downloading, linking and
loading models, the underlying functionality is entirely based on native Python
packages. This allows your application to handle a model like any other package
dependency.
<!-- TODO: reference relevant spaCy project -->
### Downloading and requiring model dependencies {#models-download}
spaCy's built-in [`download`](/api/cli#download) command is mostly intended as a
convenient, interactive wrapper. It performs compatibility checks and prints
detailed error messages and warnings. However, if you're downloading models as
part of an automated build process, this only adds an unnecessary layer of
complexity. If you know which models your application needs, you should be
specifying them directly.
Because all models are valid Python packages, you can add them to your
application's `requirements.txt`. If you're running your own internal PyPi
installation, you can upload the models there. pip's
[requirements file format](https://pip.pypa.io/en/latest/reference/pip_install/#requirements-file-format)
supports both package names to download via a PyPi server, as well as direct
URLs.
```text
### requirements.txt
spacy>=2.2.0,<3.0.0
https://github.com/explosion/spacy-models/releases/download/en_core_web_sm-2.2.0/en_core_web_sm-2.2.0.tar.gz#egg=en_core_web_sm
```
Specifying `#egg=` with the package name tells pip which package to expect from
the download URL. This way, the package won't be re-downloaded and overwritten
if it's already installed - just like when you're downloading a package from
PyPi.
All models are versioned and specify their spaCy dependency. This ensures
cross-compatibility and lets you specify exact version requirements for each
model. If you've trained your own model, you can use the
[`package`](/api/cli#package) command to generate the required meta data and
turn it into a loadable package.
### Loading and testing models {#models-loading}
Models are regular Python packages, so you can also import them as a package
using Python's native `import` syntax, and then call the `load` method to load
the model data and return an `nlp` object:
```python
import en_core_web_sm
nlp = en_core_web_sm.load()
```
In general, this approach is recommended for larger code bases, as it's more
"native", and doesn't depend on symlinks or rely on spaCy's loader to resolve
string names to model packages. If a model can't be imported, Python will raise
an `ImportError` immediately. And if a model is imported but not used, any
linter will catch that.
Similarly, it'll give you more flexibility when writing tests that require
loading models. For example, instead of writing your own `try` and `except`
logic around spaCy's loader, you can use
[pytest](http://pytest.readthedocs.io/en/latest/)'s
[`importorskip()`](https://docs.pytest.org/en/latest/builtin.html#_pytest.outcomes.importorskip)
method to only run a test if a specific model or model version is installed.
Each model package exposes a `__version__` attribute which you can also use to
perform your own version compatibility checks before loading a model.