How to use the CG-2 parser vislcg
How to use the vislcg parser
The command line looks like this (for sme, supposing you stand in the sme directory):
sme$ cat sometext.txt | preprocess --abbr=bin/abbr.txt | lookup -flags mbTT bin/sme.fst | ../script/lookup2cg | vislcg --grammar=src/sme-dis.rle | less
Flags and their use
The vislcg program contains 18 flags, or usage options. A list of the flags may be obtained by writing the following command:
i.e., by using the flag --help. The most relevant flags for our use are the following:
- This flag selects the grammar file. The "=" symbol is optional.
- This flag sets the number of CONSTRAINT sections that are applied. In this way it is possible to study the effects of one rule set at a time.
- This flag tells the parser to include information of what constraint rules are invoked in each concrete case. The flag is crucial for studying the effects of the different rules.
- The flag --minimal is used together with the flag --trace. With this flag only the line number of the rule is given. Without the --minimal flag, the parser also lists the rule in question.
For reference: Tapanainen's original CG-2 parser
Tapanainen's original CG-2 parser mdis is available from Connexor. A copy of the parser is available for staff and students on the computer of the ling.dept at the U of Helsinki, at ~tapanain/conexor/mdis/bin/. The parser cannot be used outside this computer.
The CG-2 parser is actually two different CG-2 parsers (Tap96 mentions 4 more parsers, this information is obsolete):
- mapping and disambiguation
- mapping and disambiguation, but with id numbers of the rules.
This list given here is not complete, but includes only relevant flags. For a full list, see Tap96.
- obligatorily for parsing (note the symbol "=*, in Tap96 this is still not included)
- sets the number (n) of CONSTRAINT sections. By default, all sections are applied.
- the parser does not apply rules
Thus, CG-2 differs from vislcg, that consists of only one parser (vislcg), but has more flags (also more flags than CG-2).
Tapanainen, Pasi 1996: The Constraint Grammar Parser CG-2. University of Helsinki Publications No. 27.