6 replies to this topic

[JRowe]

I've been experimenting with Link Grammar for several weeks. It's somewhat akin to a reverse regular expression. You input a regular English (or German or Italian) sentence, and it outputs a pattern parsed from the structure of the sentence.

The Link Grammar Parser is a syntactic parser of English, based on link grammar, an original theory of English syntax. Given a sentence, the system assigns to it a syntactic structure, which consists of a set of labeled links connecting pairs of words. The parser also produces a "constituent" representation of a sentence (showing noun phrases, verb phrases, etc.).

This is used in a grammar checker for a word processor, various NLP software, and is also one of the core NLP components of OpenCog.

For those of you I've lost, this is what it actually does.

Give Link Grammar a sentence like:

 "My dog likes dog food."

It outputs:

    +------------------Xp-----------------+
    +----Wd----+    +------Ou------+    |
    |   +-Ds+--Ss--+    +---AN--+   |
    |   | |     |   |   |   |
LEFT-WALL my dog.n likes.v dog.n food.n-u . 

Or, even better, it chunks the input into phrases, similar to the way your english teacher had you do in school:

(S (NP My dog) (VP likes (NP dog food)) .)

Even better, Link Grammar can take words it's unsure of and make educated guesses about the grammatical structure. Let's invent a word, like foofsnarfle. foofsnarfle is a verb that means "to throw a cow at a rapidly moving target."

My input sentence is "My brother foofsnarfled a truck." The result is correct; Link Grammar determines that foofsnarfle is a verb and generates the proper diagram.

(S (NP My brother) (VP foofsnarfled (NP a truck)) .)

LG can also output PostScript format, along with a 2D list of word - type pairs, like so:

    My.f    Ds+ 
    dog.n   Wd- Ds- Ss+ 
    likes.v Ss- Ou+ 
    dog.n   AN+ 
    food.s  Ou- AN- 
    .   Xp- 

The latest news and documentation can be found on this page: http://www.abisource.com/projects/link-grammar/
This is the documentation of the English dictionary, and what the symbols mean: http://www.abisource.com/projects/link-grammar/dict/index.html
This is the API documentation, which contains all the functions I have wrapped: http://www.abisource.com/projects/link-grammar/api/index.html

There are two additional functions that aren't documented, required for different output. Those are:

Func _LG_LinkagePrintDisjuncts($hLinkage)
    $result = DllCall($_LG_DLL, "str:cdecl", "linkage_print_disjuncts", "ptr", $hLinkage)
    Return $result[0]
EndFunc

This function provides the list of word <-> type pairs.

The other function is :

Func _LG_LinkagePrintConstituentTree($hLinkage, $iOpt)
    ;char * linkage_print_constituent_tree(Linkage linkage int iOpt);
    $result = DllCall($_LG_DLL, "str:cdecl", "linkage_print_constituent_tree", "ptr", $hLinkage, "int", $iOpt)
    Return $result[0]
EndFunc ;==>_LG_LinkagePrintConstituentTree

This outputs the parsed phrase format, explained here: http://www.link.cs.cmu.edu/link/ph-explanation.html

Here's the sample code to get you going:

AutoIt        expandcollapse  popup

#include "_LinkGrammar.au3"

$Test = "My dog likes dog food."

$options = _LG_ParseOptionsCreate()
$dict = _LG_DictionaryCreateLang("en")
$Sentence = _LG_SentenceCreate($Test, $dict)
_LG_SentenceSplit($Sentence, $options)


$num_linkages = _LG_SentenceParse($Sentence, $options)

If $num_linkages > 0 Then
    $linkage = _LG_LinkageCreate(0, $Sentence, $options)
    $diagram = _LG_LinkagePrintDiagram($linkage)
    $diagram2 = _LG_LinkagePrintConstituentTree($linkage, 3)
    $diagram3 = _LG_LinkagePrintDisjuncts($linkage)

    ConsoleWrite($diagram & @CRLF)
    ConsoleWrite($diagram2 & @CRLF)
    ConsoleWrite($diagram3 & @CRLF)
EndIf

And finally: Here's the AutoIt packge, with the dll, the English, and the German dictionaries:
http://www.AutoIt.me/_LinkGrammar_au3.zip

Enjoy!

[wraithdu]

Let's invent a word, like foofsnarfle. foofsnarfle is a verb that means "to throw a cow at a rapidly moving target."

I think a sentence like this says so much about a person. This is the kind of thing that would be in the prison psychologist's file after you've gone all Hannibal Lecter.

[JRowe]

Let's play word association! "Foofsnarfle" "Arghniblewonk" "MurderStabKill!"
Yay, I want to do Rorschach blots now!

[Erion]

Hello,
I've tried to download the linked file, however the link is no longer valid. Could someone post a working link please?
Much thanks,
Erion

[ldub]

It lacks in the autoit package : dll, English, and German dictionaries.

Thanks

[HAMID]

hi JRowe
download link not work

[DJKMan]

I'm glad I kept an archive of most of the things I found interesting!

Attached Files

•  _LinkGrammar_au3.zip   577.82K   87 downloads