A very simple sample program using the library is depicted below. It reads text from stdin, morphologically analyzes it, and processes the obtained results. Depending on the application, the input text could be obtained from a speech recongnition system, or from a XML parser, or from any source suiting the application goals.
int main() { string text; list<word> lw; list<sentence> ls; // create analyzers tokenizer tk("myTokenizerFile.dat"); splitter sp(false,0); // morphological analysis has a lot of options, and for simplicity they are packed up // in a maco_options object. First, create the maco_options object with default values. maco_options opt("es"); // set required options opt.noQuantitiesDetection = true; // deactivate quantities submodule // Data files for morphological submodules. Note that it is not necessary // to set opt.CurrencyFile, since quantities module was deactivated. opt.LocutionsFile="myMultiwordsFile.dat"; opt.SuffixFile="mySuffixesFile.dat"; opt.ProbabilityFile="myProbabilitiesFile.dat"; opt.DictionaryFile="myDictionaryFile.dat"; opt.NPdataFile="myNPdatafile.dat"; opt.PunctuationFile="myPunctuationFile.dat"; // create the analyzer with the given set of maco_options maco morfo(opt); // create a hmm tagger hmm_tagger tagger("es", "myTaggerFile.dat"); // get plain text input lines while not EOF. while (getline(cin,text)) { // clear temporary lists; lw.clear(); ls.clear(); // tokenize input line into a list of words lw=tk.tokenize(text); // accumulate list of words in splitter buffer, returning a list of sentences. // The resulting list of sentences may be empty if the splitter has still not // enough evidence to decide that a complete sentence has been found. The list // may contain more than one sentence (since a single input line may consist // of several complete sentences). ls=sp.split(lw, false); // analyze all words in all sentences of the list, enriching them with lemma and PoS // information. Some of the words may be glued in one (e.g. dates, multiwords, etc.) morfo.analyze(ls); // disambiguate words in each sentence of given sentence list. tagger.analyze(ls); // Process the enriched/disambiguated objects in the list of sentences ProcessResults(ls); } // No more lines to read. Make sure the splitter doesn't retain anything ls=sp.split(lw, true); // morphologically enrich and disambiguate last sentence(s) morfo.analyze(ls); tagger.analyze(ls); // process last sentence(s) ProcessResults(ls); }
The processing performed on the obtained results would obviously depend on the goal of the application (translation, indexation, etc.). In order to illustrate the structure of the linguistic data objects, a simple procedure is presented below, in which the processing consists of merely printing the results to stdout in XML format.
void ProcessResults(const list<sentence> &ls) { list<sentence>::const_iterator s; word::const_iterator a; //iterator over all analysis of a word sentence::const_iterator w; // for each sentence in list for (s=ls.begin(); s!=ls.end(); s++) { // print sentence XML tag cout<<"<SENT>"<<endl; // for each word in sentence for (w=s->begin(); w!=s->end(); w++) { // print word form, with PoS and lemma chosen by the tagger cout<<" <WORD form=\""<<w->get_form(); cout<<"\" lemma=\""<<w->get_lemma(); cout<<"\" pos=\""<<w->get_parole(); cout<<"\">"<<endl; // for each possible analysis in word, output lemma, parole and probability for (a=w->analysis_begin(); a!=w->analysis_end(); ++a) { // print analysis info cout<<" <ANALYSIS lemma=\""<<a->get_lemma(); cout<<"\" pos=\""<<a->get_parole(); cout<<"\" prob=\""<<a->get_prob(); cout<<"\"/>"<<endl; } // close word XML tag after list of analysis cout<<"</WORD>"<<endl; } // close sentence XML tag cout<<"</SENT>"<<endl; } }
The above sample program may be found in file FreeLing-build-dir/src/main/sample.cc
Once you have compiled and installed FreeLing, you can build this
sample program (or any other you may want to write) with the command:
g++ -o sample sample.cc -lmorfo -ldb_cxx -lpcre -lomlet -fries
Option -lmorfo links with libmorfo library, which is the final result of the
FreeLing compilation process. The oher options refer to above
mentioned libraries required by FreeLing.
You may have to add some -I and/or -L options to the
compilation command depending on where the headers and code of
required libraries are located. For instance, if you installed some
of the libraries in /usr/local/mylib instead of the default
place /usr/local, you'll have to add the options
-I/usr/local/mylib/include -L/usr/local/mylib/lib
to the command above.
More clues on how to use the freeling library from your own program may be obtained by looking at the source code of the main program provided in the package. The program is quite simple and commented, so it should be easy to understand what it does. The source can be found in file FreeLing-build-dir/src/main/analyzer.cc
2008-01-24