Lttoolbox and lexc

This page describes some how lttoolbox and HFST's lexc are similar, so that people more familiar with one can get to grips more easily with the other.

Terminology

lttoolbox	lexc	Notes
Paradigm	Continuation lexicon	So each time you see LEXICON foo, think <pardef n="foo"/>
Section	Root lexicon
Left	Up	Both left and upper correspond to surface form
Right	Down	Corresponds to lexical form
Symbol	Multichar symbol	Sequences of one or more symbol which are treated as one symbol

Example

lttoolbox

<dictionary>
  <sdefs>
    <sdef n="n"/>
    <sdef n="pl"/>
    <sdef n="sg"/>
  </sdefs>
  <pardefs> 
    <pardef n="RegNounInfl">
      <e><p><l/><r><s n="n"/><s n="sg"/></r></p></e>
      <e><p><l>s</l><r><s n="n"/><s n="pl"/></r></p></e>
    </pardef>
  </pardefs>
  <section id="Root" type="standard">
    <e lm="cat"><i>cat</i><par n="RegNounInfl"/></e> <!-- A noun -->
  </section>
</dictionary>

And to compile and use this dictionary:

$ lt-comp lr test.dix test.bin
Root@standard 7 7

$ echo "cat" | lt-proc test.bin
^cat/cat<n><sg>$

$ echo "cats" | lt-proc test.bin
^cats/cat<n><pl>$

lexc

Multichar_Symbols

 +N +Pl +Sg

LEXICON Root

NounRoot ;

LEXICON NounRoot

cat RegNounInfl ; ! A noun

LEXICON RegNounInfl

+N+Sg:   # ;
+N+Pl:s   # ;

And to compile and use this dictionary:

$ hfst-lexc test.lexc -o test.gen.hfst
$ hfst-invert -i test.gen.hfst -o test.mor.hfst

$ echo "cat" | hfst-lookup test.mor.hfst 
cat	cat+N+Sg

$ echo "cats" | hfst-lookup test.mor.hfst 
cats	cat+N+Pl