README updated with methods description and USAGE.

Author: coderjack

README.md

@@ -1 +1,43 @@
-# NLP_CODE
+#NLP_CODE
+
+This repository contains a single directory named sentence_autocomplete which is an assignment submission and is purely for academic purposes.
+Code description:
+   The code file contains a class named "MarkovChain" which contains all the essential methods for creating markov chain using trigrams from the data loaded from a output file which is inturn generated using an original input file containing raw tweets.
+   
+   Method wise description:
+      Class MarkovChain
+         Method : initialize(input_file)
+           Takes in a name of the file containing raw tweets and calls a method named "clean_data_and_save_to_file" which
+           is in a module named DataPreprocessing in the same code file. This method "clean_data_and_save_to_file"                  removes unwanted material like special characters except apostrophe and urls from the tweets and writes back 
+           the processed tweets to an output file. The initialize method then loads this file and read it line by line to
+           produce trigrams from the line and calls the "add" function to add the trigrams to the trigram hash(@word).
+         
+         Method : add(word, word1, word2)
+           Takes in three words and add the first two words as key in the dictionary(hash) and the third word as a hash 
+           this key with value as the frequency of the occurence of this trigram.
+
+         Method : get_possible_word(bigram)
+           This method takes in two word combination and look up to the dictionary we created in "add" method and finds 
+           all the keys under the main bigram. Then it calculates the weight of all the keys under this bigram and return
+           the key with highest probability or frequency of occurence.
+           Note that this method returns only one word.
+         
+         Method : print_dict
+           This method simply prints out the trigram dictionary @word.
+           
+
+USAGE:
+   Make an object of the class named "MarkovChain" and pass the input raw data text file.
+     markov_obj = MarkovChain.new(<in_file>)
+	 Pass last two words of an incomplete sentence to the method named "get_possible_word"	
+		 str = "American sniper is directed by"
+		 str_list = str.chomp.strip.split
+		 wrd1 = str_list[-2]
+		 wrd2 = str_list[-1]
+		 search_string = "#{wrd1} #{wrd2}"
+		 next_word = markov_obj.get_possible_word(search_string)
+		 
+	 To get the second possible word just pass the next_word generated before and the last word of the original incomplete sentence
+	 to the "get_possible_method" again.
+		
+