Installation
============

For stable version::

    pip install pythainlp

For development version::

    pip install --upgrade --pre pythainlp

For some functionalities, like named entity recognition, extra packages may be needed. Install them with these install options:

    pip install pythainlp[extra1,extra2,...]

where ``extras`` can be
  - ``attacut`` (to support attacut, a fast and accurate tokenizer)
  - ``icu`` (for ICU, International Components for Unicode, support in transliteration and tokenization)
  - ``ipa`` (for IPA, International Phonetic Alphabet, support in transliteration)
  - ``ml`` (to support ULMFiT models for classification)
  - ``ner`` (for named-entity recognizer)
  - ``thai2fit`` (for Thai word vector)
  - ``thai2rom`` (for machine-learnt romanization)
  - ``full`` (install everything)

For dependency details, look at `extras` variable in [`setup.py`](https://github.com/PyThaiNLP/pythainlp/blob/dev/setup.py).

Note for installation on Windows:

- ``PyICU`` libraries may required. You have two options to get them installed on Windows.

- Option 1 (recommended):
    - Find a pre-built package ("wheel") from https://www.lfd.uci.edu/~gohlke/pythonlibs/ 
    - Download a suitable wheel for your Python version (3.5, 3.6, etc.) and CPU architecture ("win32" for 32-bit Windows and "amd64" for 64-bit Windows)
    - Install them with pip. For example: `pip install PyICU-xxx‑cp36‑cp36m‑win32.whl`
    
- Option 2 (advanced):
    - You can also try to install them with a command: `pip install pyicu`
    - With this, pip will try to build the libraries directly from source files.
    - This will take some time and need a set of build tools to be installed in your system, for example Microsoft Visual C++ Compiler. It also requires some technical skills on how things are getting built on Windows system, as you may need to configure some environment variables to accommodate the build process.
    - For PyICU, before the installation, you have to set ``ICU_VERSION`` environment variable to ICU version in your system. For example, ``set ICU_VERSION=62.1``.
    - This approach is obviously take more time and effort, but the good side is the library will be optimized for your system. This could mean a better performance.


Runtime Configurations
----------------------

.. envvar:: PYTHAINLP_DATA_DIR

   This environment variable specifies the location where the downloaded data
   and the corpus database information are stored. If this directory
   does not exist, PyThaiNLP will automatically create a new one.
   By default, it is specified to the directory called ``pythainlp-data``
   within the home directory.