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GERMAN COMPOUND SPLITTER

Based on a greedy "detach word-by-word" heuristic.

PLEASE HELP WITH TEST CASES

They're much appreciated and needed. A list of test splits is in:

src/test/resources/test-compounds.utf8

It is a plain text file with a single compound on each line. For example:

lerneffekt lern.effekt

means "lerneffekt" should be split into "lern" and "effekt". Whenever there are glue morphemes, they are omitted in the split hint, as in here:

anwendungsprogrammschnittstelle anwendung.programm.schnittstelle

If there are more than one possible splits (ambiguity), they are comma-separated as in:

sünderecke sünde.recke,sünder.ecke

Add as many test cases as you want. Run them with:

mvn test

This launches a TestNG data-driven test suite.

COMPILING DICTIONARIES

A finite state automaton is created from:

src/data/morphy.txt (surface lemma POS_TAG) src/data/morphy-unknown.txt (surface lemma POS_TAG)

You can add new words to morphy-unknown.txt and recompile the automaton with:

mvn -Pfst

The result is in src/main/resources/words.fst. You'll need to refresh your IDE to pick up the changes.

TODO: PREFIXES

We need to think if "fixed" prefixes are indeed useful and should be detached/ removed in the initial stages of processing. Daniel came up with a list that I stored here:

src/data/compound-prefixes.txt

It is temporarily not used because I've tried this, for example:

$ grep -i "^abbrenn" ./consolidated.bycount abbrennen 4063 abbrennt 713 abbrennens 131 abbrennenden 80 abbrennende 62 abbrennung 56 abbrenne 45

this is Google 1-gram corpus from 1980-200(7?) and it is clear that this prefix is not a compound forming one at all.