FreeNLP

Motivation
After using NLTK and other wonderful python tools for a few years, 
it seems like it's time for dot net to have a library of similar NLP tools.

FreeNLP is an effort to enable the ease of use of nLTK in the dot net world 
without the effort of shoe-horning nltk libraries into IronPython.

currently the library only supports a couple of corpus readers and only a 
small amount of functionality in them:

The Corpus Reader support currently includes:
NLTK Treebank corpus - read raw sentences, tagged sentences, 
  and parsed sentences.

Treebank-3 corpus - read raw and parsed sentences in each of the available 
  subcorpora: ATIS Switchboard, wsj, and brown.

My plan is to provide quality corpus investigation tools which, when combined 
with Machine Learning packages like maxent or Infer.net, can be just as powerful 
as the tools available in java or python.

Use
FreeNLP is source code only.  clone the repo and compile the library.
Unlike nltk, FreeNLP does not come with any corpora.  you omust obtain the 
texts on your own.

Once you have the corpora you can do a couple of different things with FreeNLP.
Here's some usage examples below.

Example 1: Printing untagged sentences from Treebank-3

      // find Treebank-3
      var path = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments), @"Data\Treebank-3");
      
      // create a corpus reader
      var treebank = new Treebank3CorpusReader(path);

      // iterate on the contents of the corpus reader looking for text only.
      // print the first 10 sentences.
      foreach (var content in treebank.read_sents().Take(10))
      {
        Console.WriteLine(content);
      }

Example 2: split corpus terms by spaces

      var r = new Regex(@"([^\s]+)");
      foreach (var term in r.Split(FileAndFolders.AllFileContents(path)).Take(100))
      {
        Console.WriteLine(term);
      }

Example 3: get the first 100 trigrams from President washington's first inaugural address.
      // find the presidents' inaugural addresses.
      var path = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments), @"Data\inaugural");

      // open a TextCorpusReader for this corpus
      var inaugural = new TextCorpusReader(path);

      // read the first 100 trigrams ignoring commas
      foreach (var address in inaugural.words("1789-Washington.txt").Where((x) => x != ", ").NGram(3).Take(100))
        Console.WriteLine(address);

Example 4: get the 10 most frequent trigrams in all the presidents' inaugural addresses.
      // assume corpus reader as above..

      // build a frequency object for the trigrams in the corpus
      var f = new Frequencies();
      foreach (var address in inaugural.words().Where((x) => x != ", ").NGram(3))
      {
        // aggregate the trigram into a string.
        f.Add(address.DefaultIfEmpty("").Aggregate((a,b)=>a+" "+b));
      }

      // print the top 10
      foreach (var term in f.Generator().OrderBy(p => p.Value).Reverse().Take(10))
      {
        Console.WriteLine(String.Format(@"{0}: {1}", term.Key, term.Value));
      }


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License<br>
Copyright (c) 2012, Joe Dumoulin<br>
All rights reserved.<br>

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