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99a42f2b58
* Move files to strings-folder * moved the file "words" back to the original folder * moved "anagram.py" also back * fix the codespell ignore-list
121 lines
2.3 KiB
Python
121 lines
2.3 KiB
Python
# Frequency Finder
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# frequency taken from http://en.wikipedia.org/wiki/Letter_frequency
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englishLetterFreq = {
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"E": 12.70,
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"T": 9.06,
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"A": 8.17,
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"O": 7.51,
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"I": 6.97,
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"N": 6.75,
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"S": 6.33,
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"H": 6.09,
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"R": 5.99,
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"D": 4.25,
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"L": 4.03,
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"C": 2.78,
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"U": 2.76,
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"M": 2.41,
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"W": 2.36,
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"F": 2.23,
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"G": 2.02,
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"Y": 1.97,
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"P": 1.93,
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"B": 1.29,
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"V": 0.98,
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"K": 0.77,
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"J": 0.15,
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"X": 0.15,
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"Q": 0.10,
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"Z": 0.07,
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}
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ETAOIN = "ETAOINSHRDLCUMWFGYPBVKJXQZ"
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LETTERS = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
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def getLetterCount(message):
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letterCount = {
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"A": 0,
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"B": 0,
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"C": 0,
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"D": 0,
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"E": 0,
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"F": 0,
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"G": 0,
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"H": 0,
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"I": 0,
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"J": 0,
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"K": 0,
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"L": 0,
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"M": 0,
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"N": 0,
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"O": 0,
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"P": 0,
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"Q": 0,
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"R": 0,
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"S": 0,
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"T": 0,
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"U": 0,
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"V": 0,
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"W": 0,
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"X": 0,
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"Y": 0,
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"Z": 0,
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}
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for letter in message.upper():
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if letter in LETTERS:
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letterCount[letter] += 1
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return letterCount
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def getItemAtIndexZero(x):
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return x[0]
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def getFrequencyOrder(message):
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letterToFreq = getLetterCount(message)
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freqToLetter = {}
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for letter in LETTERS:
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if letterToFreq[letter] not in freqToLetter:
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freqToLetter[letterToFreq[letter]] = [letter]
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else:
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freqToLetter[letterToFreq[letter]].append(letter)
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for freq in freqToLetter:
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freqToLetter[freq].sort(key=ETAOIN.find, reverse=True)
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freqToLetter[freq] = "".join(freqToLetter[freq])
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freqPairs = list(freqToLetter.items())
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freqPairs.sort(key=getItemAtIndexZero, reverse=True)
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freqOrder = []
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for freqPair in freqPairs:
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freqOrder.append(freqPair[1])
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return "".join(freqOrder)
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def englishFreqMatchScore(message):
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"""
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>>> englishFreqMatchScore('Hello World')
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1
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"""
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freqOrder = getFrequencyOrder(message)
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matchScore = 0
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for commonLetter in ETAOIN[:6]:
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if commonLetter in freqOrder[:6]:
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matchScore += 1
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for uncommonLetter in ETAOIN[-6:]:
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if uncommonLetter in freqOrder[-6:]:
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matchScore += 1
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return matchScore
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if __name__ == "__main__":
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import doctest
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doctest.testmod()
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