Apertium separable

Lttoolbox provides a module for reordering separable/discontiguous multiwords and processing them in the pipeline. Multiwords are manually written in an additional xml-format dictionary.

Installing

Prerequisites and compilation are the same as lttoolbox and apertium. See Installation. The code can be found at https://svn.code.sf.net/p/apertium/svn/branches/apertium-separable/src and instructions for compilation are below.

It is not currently part of distributed Apertium binaries.

Lexical transfer in the pipeline

lsx-proc runs between apertium-tagger and apertium-pretransfer:

… | apertium-tagger -g eng.prob | lsx-proc english.bin | apertium-pretransfer | …

Example

A sentence in plain text,

Thus, it was asserted that a tax on foreign workers would reduce the numbers coming in and “taking jobs away” from American citizens.

This is the output of feeding the sentence through apertium-tagger :

^thus<adv>$^,<cm>$ ^prpers<prn><subj><p3><nt><sg>$ ^be<vbser><past><p3><sg>$ ^assert<vblex><pp>$ ^that<prn><tn><mf><sg>$ ^a<det><ind><sg>$ ^tax<n><sg>$ ^on<pr>$ ^foreign<adj>$ ^worker<n><pl>$ ^would<vaux><inf>$ ^reduce<vblex><inf>$ ^the<det><def><sp>$ ^number<vblex><pri><p3><sg>$ ^come<vblex><ger># in$ ^and<cnjcoo>$ “^take<vblex><ger>$ ^job<n><pl>$ ^away<adv>$” ^from<pr>$ ^american<adj>$ ^citizen<n><pl>$^.<sent>$^.<sent>$

This is the output of feeding the output above through lsx-proc :

^thus<adv>$^,<cm>$ ^prpers<prn><subj><p3><nt><sg>$ ^be<vbser><past><p3><sg>$ ^assert<vblex><pp>$ ^that<prn><tn><mf><sg>$ ^a<det><ind><sg>$ ^tax<n><sg>$ ^on<pr>$ ^foreign<adj>$ ^worker<n><pl>$ ^would<vaux><inf>$ ^reduce<vblex><inf>$ ^the<det><def><sp>$ ^number<vblex><pri><p3><sg>$ ^come<vblex><ger># in$ ^and<cnjcoo>$ “^take# away<vblex><sep><ger>$ ^job<n><pl>$” ^from<pr>$ ^american<adj>$ ^citizen<n><pl>$^.<sent>$^.<sent>$

Compilation and Usage

Make a dictionary file:

<dictionary type="separable">
    <alphabet>ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz</alphabet>
    <sdefs>
        <sdef n="adj"/>
        <sdef n="adv"/>
        <sdef n="n"/>
        <sdef n="sep"/>
        <sdef n="vblex"/>
    </sdefs>
    <pardefs>
        <pardef n="adj">
            <e><i><w/><s n="adj"/><j/></i></e>
            <e><i><w/><s n="adj"/><t/><j/></i></e>
        </pardef>
        <pardef n="n">
            <e><i><w/><s n="n"/><t/><j/></i></e>
        </pardef>
        <pardef n="SN">
            <e><par n="n"/></e>
            <e><par n="adj"/><par n="n"/></e>
            <e><par n="adj"/><par n="adj"/><par n="n"/></e>
        </pardef>
        <pardef n="freq-adv">
            <e><i>always<s n="adv"/><j/></i></e>
            <e><i>anually<s n="adv"/><j/></i></e>
            <e><i>bianually<s n="adv"/><j/></i></e>
        </pardef>
    </pardefs>
    <section id="main" type="standard">
        <e lm="be late" c="llegar tarde">
            <p><l>be<s n="vblex"/></l><r>be<g><b/>late</g><s n="vblex"/><s n="sep"/></r></p><i><t/><j/></i>
            <par n="freq-adv"/><p><l>late<t/></l><r></r></p>
        </e>
        <e lm="take away" c="sacar, quitar">
            <p><l>take<s n="vblex"/></l><r>take<g><b/>away</g><s n="vblex"/><s n="sep"/></r></p><i><t/><j/></i>
            <par n="SN"/><p><l>away<t/></l><r></r></p>
        </e>
    </section>
</dictionary>

Note:

• <w/> stands for one or more alphabetic symbols
• <t/> stands for one or more tags (multicharacter symbols).

i.e.

• <e><w/><t/><j/></e> is equivalent to any-one-or-more-chars<adj><required-anytag><optional-anytag><...>
• <e><w/><j/></e> is equivalent to any-one-or-more-chars<adj><optional-anytag><...>

Then compile it:

$ lsx-comp dictionary.xml english.bin
main@standard 61 73

The input to lsx-proc is the output of apertium-tagger ,

$ echo '^thus<adv>$^,<cm>$ ^prpers<prn><subj><p3><nt><sg>$ ^be<vbser><past><p3><sg>$ ^assert<vblex><pp>$ ^that<prn><tn><mf><sg>$ ^a<det><ind><sg>$ ^tax<n><sg>$ ^on<pr>$ ^foreign<adj>$ ^worker<n><pl>$ ^would<vaux><inf>$ ^reduce<vblex><inf>$ ^the<det><def><sp>$ ^number<vblex><pri><p3><sg>$ ^come<vblex><ger># in$ ^and<cnjcoo>$ <b>“^take<vblex><ger>$ ^job<n><pl>$ ^away<adv>$”</b> ^from<pr>$ ^american<adj>$ ^citizen<n><pl>$^.<sent>$^.<sent>$' | lsx-proc english.bin

A larger example dictionary can be found at https://svn.code.sf.net/p/apertium/svn/branches/apertium-separable/examples/new-example.dix

Dictionary format

A paradigm is made up of:

A dictionary entry is made up of:

Preparedness of languages

Language	entries
apertium-eng	18,563

Todo and bugs

• Decide whether the lsx module is part of monolingual modules, language pairs, either, or both.
• Instead of dictionary.xml and english.bin and the like, we should have standardised naming conventions. Some options/proposals:
  • eng-cat.autolsx.xml, eng-cat.autolsx.bin
  • eng-cat.autosep.lsx, eng-cat.autosep.bin
  • ...

See also

• Apertium system architecture

References

• https://svn.code.sf.net/p/apertium/svn/branches/apertium-separable/src
• project proposal and workplan