170 http://inventwithpython.com/hacking

Email questions to the author: [email protected]

29. if possibleWords == []:


30. return 0.0 # no words at all, so return 0.0


31. 
    


32. matches = 0


33. for word in possibleWords:


34. if word in ENGLISH_WORDS:


35. matches += 1


36. return float(matches) / len(possibleWords)


37. 
    


38. 
    


39. def removeNonLetters(message):


40. lettersOnly = []


41. for symbol in message:


42. if symbol in LETTERS_AND_SPACE:


43. lettersOnly.append(symbol)


44. return ''.join(lettersOnly)


45. 
    


46. 
    


47. def isEnglish(message, wordPercentage=20, letterPercentage= 85 ):


48. 
    

    By default, 20% of the words must exist in the dictionary file, and

    
    


49. 
    

    85% of all the characters in the message must be letters or spaces

    
    


50. 
    

    (not punctuation or numbers).

    
    


51. wordsMatch = getEnglishCount(message) * 100 >= wordPercentage


52. numLetters = len(removeNonLetters(message))


53. messageLettersPercentage = float(numLetters) / len(message) * 100


54. lettersMatch = messageLettersPercentage >= letterPercentage


55. return wordsMatch and lettersMatch

How the Program Works..........................................................................................................................................

detectEnglish.py

1. 
   

   Detect English module

   
   


2. 
   

   http://inventwithpython.com/hacking (BSD Licensed)

   
   


3. 
   


4. 
   

   To use, type this code:

   
   


5. 
   

   import detectEnglish

   
   


6. 
   

   detectEnglish.isEnglish(someString) # returns True or False

   
   


7. 
   

   (There must be a "dictionary.txt" file in this directory with all English

   
   


8. 
   

   words in it, one word per line. You can download this from

   
   


9. 
   

   http://invpy.com/dictionary.txt))

   
   

These comments at the top of the file give instructions to programmers on how to use this
module. They give the important reminder that if there is no file named dictionary.txt in the same