Conversions between GF and dependency trees, in particular UD (Universal Dependencies) but designed to be completely generic as for annotation scheme. This repository replaces the old gf-contrib/ud2gf code.

The conversions are based on algorithms presented in the papers

• P Kolachina and A Ranta, From Abstract Syntax to Universal Dependencies, LiLT (Linguistic Issues in Language Technology) 13, 2016 ("gf2ud") http://csli-lilt.stanford.edu/ojs/index.php/LiLT/article/view/71/73

• A Ranta and P Kolachina, From Universal Dependencies to Abstract Syntax, Proceedings of the NoDaLiDa 2017 Workshop on Universal Dependencies, 2017 ("ud2gf") https://www.aclweb.org/anthology/W17-0414.pdf

as well as some earlier code in gf-contrib/ud2gf and in gf-core/src/, mostly by Aarne Ranta and Prasanth Kolachina. Differences from those sources may be documented later.

To get started, you can test the following:

• cd grammars
• ln -s gf-summerschool-2018 # a sister Git repository
• make mini
• cd ..
• make compile
• cat test.conllu | ./gfud -ud2gf grammars/MiniLang Eng Utt at
• cat test.gftrees | ./gfud -gf2ud grammars/MiniLang Eng Utt ud
• echo "the black cat sees us" | ./gfud -string2gf2ud grammars/MiniLang Eng Utt

You can also follow the instructions in doc/training-and-testing.txt to test a combination with Malt parser.

The largest changes are perhaps in the format of dependency configurations. One goal was to merge the gf2ud and ud2gf annotations. See

• grammars/MiniLang.labels
• grammars/MiniLangEng.labels

for examples (to be documented properly later).

Other grammars to try are

• grammars/ShallowParse # wide-coverage, with WordNet words but without sense distinctions, uses sister repo gf-wordnet/
• grammars/Term # a grammar of arithmetic expression, completely different tagset

With ShallowParse, you can try out the included sample from https://github.com/UniversalDependencies/UD_English-PUD/blob/master/en_pud-ud-test.conllu

• cat upto12eng.conllu | ./gfud -ud2gf grammars/ShallowParse Eng Text at stat

But the results are still meager, and require additions in ShallowParse.labels and maybe in the algorithm.