NAME

Alvis::TermTagger - Perl extension for tagging terms in a corpus

SYNOPSIS

use Alvis::TermTagger;

Alvis::TermTagger::termtagging($termlist, $outputfile);

DESCRIPTION

This module is used to tag a corpus with terms. Corpus (given on the STDIN) is a file with one sentence per line. Term list ($termlist) is a file containing one term per line. For each term, additionnal information (as canonical form) can be given after a column. Each line of the output file ($outputfile) contains the sentence number, the term, additional information, all separated by a tabulation character.

This module is mainly used in the Alvis NLP Platform.

METHODS

`termtagging()`

    termtagging($term_list_filename, $output_filename);

This is the main method of module. It loads the term list ($term_list_filename) and tags the corpus ($corpus_filename). It produces the list of matching terms and the sentence offset (and additional information given in the input file) where the terms can be found. The file $output_filename contains this output.

`load_TermList()`

    load_TermList($term_list_filename,\@term_list);

This method loads the term list ($term_list_filename is the file name) in the array given by reference (\@term_list). Each element of term list contains a reference to a two element array (the term and its canonical form).

`get_Regex_TermList()`

    get_Regex_TermList(\@term_list, \@regex_term_list);

This method generates the regular expression from the term list (\@term_list). stored in the specific array (\@regex_term_list)

`load_Corpus()`

    load_Corpus($corpus_filename\%corpus, \%lc_corpus);

This method loads the corpus ($corpus_filename) in hashtable (\%corpus) and prepares the corpus in lower case (recorded in a specific hashtable, \%lc_corpus)

`corpus_Indexing()`

    corpus_Indexing(\%lc_corpus, \%corpus_index);

This method indexes the lower case version of the corpus (\%lc_corpus) according the words \%corpus_index (the index is a hashtable given by reference).

`term_Selection()`

    term_Selection(\%corpus_index, \@term_list, \%idtrm_select);

This method selects the terms from the term list (\@term_list) potentially appearing in the corpus (that is the indexed corpus, \%corpus_index). Results are recorded in the hash table \%idtrm_select.

`term_tagging_offset()`

    term_tagging_offset(\@term_list, \@regex_term_list, \%idtrm_select, \%corpus, $output_filename);

`term_tagging_offset_tab()`

    term_tagging_offset(\@term_list, \@regex_term_list, \%idtrm_select, \%corpus, \@tab_results);

    term_tagging_offset(\@term_list, \@regex_term_list, \%idtrm_select, \%corpus, \%tabh_results);

This method tags the corpus \%corpus with the terms (issued from the term list \@term_list, \@regex_term_list is the term list with regular expression), and selected in a previous step (\%idtrm_select). Resulting selected terms are recorded with their offset, and additional information in the array @tab_results (values are sentence id, selected terms and additional information separated by tabulation) or in the hashtable %tabh_results (keys form is ``sentenceid_selectedterm'', values are an array reference containing sentence id, selected terms and additional ifnormation).

printMatchingTerm

    printMatchingTerm($descriptor, $ref_matching_term, $sentence_id);

This method prints into the file descriptor $descriptor, the sentence id ($sentence_id) and the matching term (named by its reference $ref_matching_term). Both data are on a line and are separated by a tabulation character.

printMatchingTerm_tab

    printMatchingTerm_tab($ref_matching_term, $sentence_id, $ref_tab_results);

This method stores into $ref_tab_results, the sentence id ($sentence_id) and the matching term (named by its reference $ref_matching_term). $ref_tab_results can be a array or a hash table. In case of an array, both data are concatanated in a line and are separated by a tabulation character. In case of a hash table, both data are stored in an array, hash key is the concatenation of the sentence id and the matching term.

AUTHORS

Thierry Hamon <thierry.hamon@lipn.univ-paris13.fr>

LICENSE

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.6 or, at your option, any later version of Perl 5 you may have available.

Alvis::TermTagger - Perl extension for tagging terms in a corpus