Source code for indicngram.core

#!/usr/bin/env python
# -*- coding: utf-8 -*-
# Ngram
# Copyright 2008-2009 Santhosh Thottingal <santhosh.thottingal@gmail.com>
# http://www.smc.org.in
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
#
import indicsyllabifier


class Ngram:
    """
    Ngram class.You need to create an object to use the function
    """
    def syllableNgram(self, text, window_size=2):
        """
        :param text: The text to be split into ngrams.
        :type word: str.
        :param window_size: window size to be used while making the ngrams.
        :type window_size: int.
        :returns: list of syllable ngrams.
        """
        window_size = int(window_size)
        words = text.split(" ")
        ngrams = []
        for word in words:
            s = indicsyllabifier.getInstance()
            #TODO-Normalize before taking ngram!!!
            syllables = s.syllabify(word)
            syllable_count = len(syllables)
            window_start = 0
            window_end = 0
            while window_start + window_size <= syllable_count:
                if(window_start + window_size < syllable_count):
                    window_end = window_start + window_size
                else:
                    window_end = syllable_count
                ngrams.append(syllables[window_start:window_end])
                window_start = window_start+1
        return ngrams

    def letterNgram(self, word, window_size=2):
        """
        :param word: The word to be split into ngrams.
        :type word: str.
        :param window_size: window size to be used while making the ngrams.
        :type window_size: int.
        :returns: list of ngrams.
        """
        window_size = int(window_size)
        word = word.strip()
        ngrams = []
        #TODO-Normalize before taking ngram!!!
        letter_count = len(word)
        window_start = 0
        window_end = 0
        while window_start + window_size <= letter_count:
            if(window_start + window_size < letter_count):
                window_end = window_start + window_size
            else:
                window_end = letter_count
            ngrams.append(word[window_start:window_end])
            window_start = window_start+1
        return ngrams

    def wordNgram(self, text, window_size=2):
        """
        :param text: The text to be split into ngrams.
        :type word: str.
        :param window_size: window size to be used while making the ngrams.
        :type window_size: int.
        :returns: list of word ngrams.
        """
        window_size = int(window_size)
        words = text.split()
        ngrams = []
        word_count = len(words)
        window_start = 0
        window_end = 0
        while window_start + window_size <= word_count:
            if(window_start + window_size < word_count):
                window_end = window_start + window_size
            else:
                window_end = word_count
            words[window_start:window_end]
            ngrams.append(words[window_start:window_end])
            window_start = window_start+1
        return ngrams

    def get_module_name(self):
        """
        returns the module's name
        """
        return "Ngram Library"

    def get_info(self):
        """
        returns info on the module
        """
        return "Ngram Library for English and Indian languages"


def getInstance():
    return Ngram()