Treebank transformation tool. A vintage 2008 code, revived for Universal Dependencies treebank conversions.

Running

Apply rewrite rules from example_rules.lp2lp to a small fragment of the English UD treebank. CoNLL-U in. CoNLL-U out.

./dtree_dep2dep.sh -r example_rules.lp2lp < ud_english_example.conllu > ud_english_example_tr.conllu

Rule syntax

Documented in example_rules.lp2lp.

Installation

dep2dep uses Prolog as the back-end rule application engine, and a little shimming module to pass data between Python and Prolog, which needs to be compiled (no Cython back then). On a newish system, this should be as easy as installing a handful of packages and then typing make.

Ubuntu

The following is tested to work on the official Ubuntu cloud image 16.04

sudo apt install git build-essential swi-prolog-nox libpcre3-dev python-dev 
git clone https://github.com/TurkuNLP/dep2dep.git
cd dep2dep
make
./dtree_dep2dep.sh -r example_rules.lp2lp < ud_english_example.conllu

Generic instructions

In order to successfully compile the lp2lp transformation library, you need to have the following environment:

1. Installation of SWI prolog with the development tools

   • header files in (by default) /usr/lib/swi-prolog/include (you can edit the Makefile if the headers are elsewhere)
   • libraries (at least):
     • libpl (prolog)
     • libgmp (numerical library for prolog)
   • the plld program (comes with SWI prolog)

2. Installation of PCRE with the development tools

   • header files (pcre.h)
   • libraries
     • libpcre

3. A 2.X Python with header files

Then just type 'make'.

Debugging

The Makefile and dtree_dep2dep.sh have few hard-coded paths. So if you have libraries and headers in non-standard locations, then you may get errors about missing symbols and the like. Just check and fix these paths.