Implementing-cryptography-using-python

134 Chapter 4 ■ Cryptographic Math and Frequency Analysis
def getTextOnly(text):
# Strip out all non-alphabet characters
# There are a number of ways to do this but this is the simplest to
understand
modifiedText = str(text.strip())
modifiedText = modifiedText.replace(" ", "")
modifiedText = " ".join(modifiedText.split())
modifiedText = modifiedText.lower()
return modifiedText
def getEncryptedData():
encryptedFilePath = "https://raw.githubusercontent.com/noidentity29/
AppliedCryptoPython/master/encryptedmoby.txt"
response = urllib.request.urlopen(encryptedFilePath, context=ssl._
create_unverified_context())
readText = response.read()
readText = readText.decode('utf-8')
textOnly = getTextOnly(readText)
return textOnly
def getFitnessScore(message, longerwords):
score = 0.0
for word in longerwords:
wordWeight = message.count(word)
if wordWeight>0:
score += wordWeight * 50 * len(word)
return score
def getDictionary():
commonWordsPath = "https://raw.githubusercontent.com/noidentity29/
AppliedCryptoPython/master/common_en_words.txt"
ALPHA = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
# create URL request
response = urllib.request.urlopen(commonWordsPath, context=ssl._
create_unverified_context())
readText = response.read()
# the file is in a binary format, decode
fileOfWords = readText.decode('utf-8')
# create an array for each word
words = fileOfWords.split()
# filter out the shorter words
longerwords = list(filter(lambda x: len(x)> 2, words))