Installing OpenFST Native Python Extension on MacOS

openfst_python_on_macos.md

Installing OpenFst Native Python Extension on MacOS

Starting from version 1.5, OpenFst has offered a native Python module, making the use of external wrappers like PyFst unnecessary. This has been greatly helpful since PyFst doesn't support Python 3.

1. Install OpenFst

• Download OpenFst 1.5.4 or above from http://openfst.cs.nyu.edu/twiki/bin/view/FST/FstDownload

• Unzip, untar: $ tar xzvf openfst-1.5.4.tar.gz

• $ ./configure --enable-python --enable-far

  • --enable-far will make OpenFst install the library files needed for the Python OpenFst extension.
  • --enable-python will install the pywrapfst Python module, but not neccessarily to the Python version you intend to use. You may need to set the global Python version to 2.7, for example using pyenv.

• $ ./make

• $ ./make install

2. Optional: create a Python virtual environment

Say you want to use Python 3.6:

• $ virtualenv -p $(which python3.6) venv
• $ source venv/bin/activate

3. Install the OpenFst Python package

• $ export CFLAGS="-std=c++11 -stdlib=libc++ -mmacosx-version-min=10.7"
  • -std=c++11 makes the compiler use the correct C standard for OpenFst
  • -stdlib=libc++ makes the compiler use the standard C library OpenFst uses
• $ pip install openfst

4. Using the Python module

See http://www.openfst.org/twiki/bin/view/FST/PythonExtension

Nur Lan 2016 https://github.com/0xnurl

If we run into installation issues with make, can we do to fix?

make[3]: *** [fstarcsort] Error 1
make[2]: *** [all-recursive] Error 1
make[1]: *** [all-recursive] Error 1