+++ /dev/null
-from utilities import *
-from language_models import *
-from itertools import chain
-
-from logger import logger
-
-def make_cadenus_keycolumn(doubled_letters = 'vw', start='a', reverse=False):
- """Makes the key column for a Cadenus cipher (the column down between the
- rows of letters)
-
- >>> make_cadenus_keycolumn()['a']
- 0
- >>> make_cadenus_keycolumn()['b']
- 1
- >>> make_cadenus_keycolumn()['c']
- 2
- >>> make_cadenus_keycolumn()['v']
- 21
- >>> make_cadenus_keycolumn()['w']
- 21
- >>> make_cadenus_keycolumn()['z']
- 24
- >>> make_cadenus_keycolumn(doubled_letters='ij', start='b', reverse=True)['a']
- 1
- >>> make_cadenus_keycolumn(doubled_letters='ij', start='b', reverse=True)['b']
- 0
- >>> make_cadenus_keycolumn(doubled_letters='ij', start='b', reverse=True)['c']
- 24
- >>> make_cadenus_keycolumn(doubled_letters='ij', start='b', reverse=True)['i']
- 18
- >>> make_cadenus_keycolumn(doubled_letters='ij', start='b', reverse=True)['j']
- 18
- >>> make_cadenus_keycolumn(doubled_letters='ij', start='b', reverse=True)['v']
- 6
- >>> make_cadenus_keycolumn(doubled_letters='ij', start='b', reverse=True)['z']
- 2
- """
- index_to_remove = string.ascii_lowercase.find(doubled_letters[0])
- short_alphabet = string.ascii_lowercase[:index_to_remove] + string.ascii_lowercase[index_to_remove+1:]
- if reverse:
- short_alphabet = cat(reversed(short_alphabet))
- start_pos = short_alphabet.find(start)
- rotated_alphabet = short_alphabet[start_pos:] + short_alphabet[:start_pos]
- keycolumn = {l: i for i, l in enumerate(rotated_alphabet)}
- keycolumn[doubled_letters[0]] = keycolumn[doubled_letters[1]]
- return keycolumn
-
-def cadenus_encipher(message, keyword, keycolumn, fillvalue='a'):
- """Encipher with the Cadenus cipher
-
- >>> cadenus_encipher(sanitise('Whoever has made a voyage up the Hudson ' \
- 'must remember the Kaatskill mountains. ' \
- 'They are a dismembered branch of the great'), \
- 'wink', \
- make_cadenus_keycolumn(doubled_letters='vw', start='a', reverse=True))
- 'antodeleeeuhrsidrbhmhdrrhnimefmthgeaetakseomehetyaasuvoyegrastmmuuaeenabbtpchehtarorikswosmvaleatned'
- >>> cadenus_encipher(sanitise('a severe limitation on the usefulness of ' \
- 'the cadenus is that every message must be ' \
- 'a multiple of twenty-five letters long'), \
- 'easy', \
- make_cadenus_keycolumn(doubled_letters='vw', start='a', reverse=True))
- 'systretomtattlusoatleeesfiyheasdfnmschbhneuvsnpmtofarenuseieeieltarlmentieetogevesitfaisltngeeuvowul'
- """
- rows = chunks(message, len(message) // 25, fillvalue=fillvalue)
- columns = zip(*rows)
- rotated_columns = [col[start:] + col[:start] for start, col in zip([keycolumn[l] for l in keyword], columns)]
- rotated_rows = zip(*rotated_columns)
- transpositions = transpositions_of(keyword)
- transposed = [transpose(r, transpositions) for r in rotated_rows]
- return cat(chain(*transposed))
-
-def cadenus_decipher(message, keyword, keycolumn, fillvalue='a'):
- """
- >>> cadenus_decipher('antodeleeeuhrsidrbhmhdrrhnimefmthgeaetakseomehetyaa' \
- 'suvoyegrastmmuuaeenabbtpchehtarorikswosmvaleatned', \
- 'wink', \
- make_cadenus_keycolumn(reverse=True))
- 'whoeverhasmadeavoyageupthehudsonmustrememberthekaatskillmountainstheyareadismemberedbranchofthegreat'
- >>> cadenus_decipher('systretomtattlusoatleeesfiyheasdfnmschbhneuvsnpmtof' \
- 'arenuseieeieltarlmentieetogevesitfaisltngeeuvowul', \
- 'easy', \
- make_cadenus_keycolumn(reverse=True))
- 'aseverelimitationontheusefulnessofthecadenusisthateverymessagemustbeamultipleoftwentyfiveletterslong'
- """
- rows = chunks(message, len(message) // 25, fillvalue=fillvalue)
- transpositions = transpositions_of(keyword)
- untransposed_rows = [untranspose(r, transpositions) for r in rows]
- columns = zip(*untransposed_rows)
- rotated_columns = [col[-start:] + col[:-start] for start, col in zip([keycolumn[l] for l in keyword], columns)]
- rotated_rows = zip(*rotated_columns)
- # return rotated_columns
- return cat(chain(*rotated_rows))
-
-if __name__ == "__main__":
- import doctest
\ No newline at end of file