+
+def vigenere_encipher(message, keyword):
+ """Vigenere encipher
+
+ >>> vigenere_encipher('hello', 'abc')
+ 'hfnlp'
+ """
+ shifts = [ord(l) - ord('a') for l in sanitise(keyword)]
+ pairs = zip(message, cycle(shifts))
+ return cat([caesar_encipher_letter(l, k) for l, k in pairs])
+
+def vigenere_decipher(message, keyword):
+ """Vigenere decipher
+
+ >>> vigenere_decipher('hfnlp', 'abc')
+ 'hello'
+ """
+ shifts = [ord(l) - ord('a') for l in sanitise(keyword)]
+ pairs = zip(message, cycle(shifts))
+ return cat([caesar_decipher_letter(l, k) for l, k in pairs])
+
+
+def beaufort_encipher(message, keyword):
+ """Beaufort encipher
+
+ >>> beaufort_encipher('inhisjournaldatedtheidesofoctober', 'arcanaimperii')
+ 'sevsvrusyrrxfayyxuteemazudmpjmmwr'
+ """
+ shifts = [pos(l) for l in sanitise(keyword)]
+ pairs = zip(message, cycle(shifts))
+ return cat([unpos(k - pos(l)) for l, k in pairs])
+
+beaufort_decipher = beaufort_encipher
+
+beaufort_variant_encipher=vigenere_decipher
+beaufort_variant_decipher=vigenere_encipher
+
+
+def polybius_grid(keyword, column_order, row_order, letters_to_merge=None,
+ wrap_alphabet=KeywordWrapAlphabet.from_a):
+ """Grid for a Polybius cipher, using a keyword to rearrange the
+ alphabet.
+
+
+ >>> polybius_grid('a', 'abcde', 'abcde')['x'] == ('e', 'c')
+ True
+ >>> polybius_grid('elephant', 'abcde', 'abcde')['e'] == ('a', 'a')
+ True
+ >>> polybius_grid('elephant', 'abcde', 'abcde')['b'] == ('b', 'c')
+ True
+ """
+ alphabet = keyword_cipher_alphabet_of(keyword, wrap_alphabet=wrap_alphabet)
+ if letters_to_merge is None:
+ letters_to_merge = {'j': 'i'}
+ grid = {l: k
+ for k, l in zip([(c, r) for c in column_order for r in row_order],
+ [l for l in alphabet if l not in letters_to_merge])}
+ for l in letters_to_merge:
+ grid[l] = grid[letters_to_merge[l]]
+ return grid
+
+def polybius_reverse_grid(keyword, column_order, row_order, letters_to_merge=None,
+ wrap_alphabet=KeywordWrapAlphabet.from_a):
+ """Grid for decrypting using a Polybius cipher, using a keyword to
+ rearrange the alphabet.
+
+ >>> polybius_reverse_grid('a', 'abcde', 'abcde')['e', 'c'] == 'x'
+ True
+ >>> polybius_reverse_grid('elephant', 'abcde', 'abcde')['a', 'a'] == 'e'
+ True
+ >>> polybius_reverse_grid('elephant', 'abcde', 'abcde')['b', 'c'] == 'b'
+ True
+ """
+ alphabet = keyword_cipher_alphabet_of(keyword, wrap_alphabet=wrap_alphabet)
+ if letters_to_merge is None:
+ letters_to_merge = {'j': 'i'}
+ grid = {k: l
+ for k, l in zip([(c, r) for c in column_order for r in row_order],
+ [l for l in alphabet if l not in letters_to_merge])}
+ return grid
+
+
+def polybius_flatten(pair, column_first):
+ """Convert a series of pairs into a single list of characters"""
+ if column_first:
+ return str(pair[1]) + str(pair[0])
+ else:
+ return str(pair[0]) + str(pair[1])
+
+def polybius_encipher(message, keyword, column_order, row_order,
+ column_first=False,
+ letters_to_merge=None, wrap_alphabet=KeywordWrapAlphabet.from_a):
+ """Encipher a message with Polybius cipher, using a keyword to rearrange
+ the alphabet
+
+
+ >>> polybius_encipher('this is a test message for the ' \
+ 'polybius decipherment', 'elephant', \
+ [1, 2, 3, 4, 5], [1, 2, 3, 4, 5], \
+ wrap_alphabet=KeywordWrapAlphabet.from_last)
+ '2214445544551522115522511155551543114252542214111352123234442355411135441314115451112122'
+ >>> polybius_encipher('this is a test message for the ' \
+ 'polybius decipherment', 'elephant', 'abcde', 'abcde', \
+ column_first=False)
+ 'bbadccddccddaebbaaddbbceaaddddaecbaacadadcbbadaaacdaabedbcccdeddbeaabdccacadaadcceaababb'
+ >>> polybius_encipher('this is a test message for the ' \
+ 'polybius decipherment', 'elephant', 'abcde', 'abcde', \
+ column_first=True)
+ 'bbdaccddccddeabbaaddbbecaaddddeabcaaacadcdbbdaaacaadbadecbccedddebaadbcccadaaacdecaaabbb'
+ """
+ grid = polybius_grid(keyword, column_order, row_order, letters_to_merge, wrap_alphabet)
+ return cat(polybius_flatten(grid[l], column_first)
+ for l in message
+ if l in grid)
+
+
+def polybius_decipher(message, keyword, column_order, row_order,
+ column_first=False,
+ letters_to_merge=None, wrap_alphabet=KeywordWrapAlphabet.from_a):
+ """Decipher a message with a Polybius cipher, using a keyword to rearrange
+ the alphabet
+
+ >>> polybius_decipher('bbdaccddccddeabbaaddbbecaaddddeabcaaacadcdbbdaaaca'\
+ 'adbadecbccedddebaadbcccadaaacdecaaabbb', 'elephant', 'abcde', 'abcde', \
+ column_first=False)
+ 'toisisvtestxessvbephktoefhnugiysweqifoekxelt'
+
+ >>> polybius_decipher('bbdaccddccddeabbaaddbbecaaddddeabcaaacadcdbbdaaaca'\
+ 'adbadecbccedddebaadbcccadaaacdecaaabbb', 'elephant', 'abcde', 'abcde', \
+ column_first=True)
+ 'thisisatestmessageforthepolybiusdecipherment'
+ """
+ grid = polybius_reverse_grid(keyword, column_order, row_order, letters_to_merge, wrap_alphabet)
+ column_index_type = type(column_order[0])
+ row_index_type = type(row_order[0])
+ if column_first:
+ pairs = [(column_index_type(p[1]), row_index_type(p[0])) for p in chunks(message, 2)]
+ else:
+ pairs = [(row_index_type(p[0]), column_index_type(p[1])) for p in chunks(message, 2)]
+ return cat(grid[p] for p in pairs if p in grid)
+
+
+def transpositions_of(keyword):
+ """Finds the transpostions given by a keyword. For instance, the keyword
+ 'clever' rearranges to 'celrv', so the first column (0) stays first, the
+ second column (1) moves to third, the third column (2) moves to second,
+ and so on.
+
+ If passed a tuple, assume it's already a transposition and just return it.
+
+ >>> transpositions_of('clever')
+ (0, 2, 1, 4, 3)
+ >>> transpositions_of('fred')
+ (3, 2, 0, 1)
+ >>> transpositions_of((3, 2, 0, 1))
+ (3, 2, 0, 1)
+ """
+ if isinstance(keyword, tuple):
+ return keyword
+ else:
+ key = deduplicate(keyword)
+ transpositions = tuple(key.index(l) for l in sorted(key))
+ return transpositions
+
+def pad(message_len, group_len, fillvalue):
+ padding_length = group_len - message_len % group_len
+ if padding_length == group_len: padding_length = 0
+ padding = ''
+ for i in range(padding_length):
+ if callable(fillvalue):
+ padding += fillvalue()
+ else:
+ padding += fillvalue
+ return padding
+
+def column_transposition_encipher(message, keyword, fillvalue=' ',
+ fillcolumnwise=False,
+ emptycolumnwise=False):
+ """Enciphers using the column transposition cipher.
+ Message is padded to allow all rows to be the same length.
+
+ >>> column_transposition_encipher('hellothere', 'abcdef', fillcolumnwise=True)
+ 'hlohr eltee '
+ >>> column_transposition_encipher('hellothere', 'abcdef', fillcolumnwise=True, emptycolumnwise=True)
+ 'hellothere '
+ >>> column_transposition_encipher('hellothere', 'abcdef')
+ 'hellothere '
+ >>> column_transposition_encipher('hellothere', 'abcde')
+ 'hellothere'
+ >>> column_transposition_encipher('hellothere', 'abcde', fillcolumnwise=True, emptycolumnwise=True)
+ 'hellothere'
+ >>> column_transposition_encipher('hellothere', 'abcde', fillcolumnwise=True, emptycolumnwise=False)
+ 'hlohreltee'
+ >>> column_transposition_encipher('hellothere', 'abcde', fillcolumnwise=False, emptycolumnwise=True)
+ 'htehlelroe'
+ >>> column_transposition_encipher('hellothere', 'abcde', fillcolumnwise=False, emptycolumnwise=False)
+ 'hellothere'
+ >>> column_transposition_encipher('hellothere', 'clever', fillcolumnwise=True, emptycolumnwise=True)
+ 'heotllrehe'
+ >>> column_transposition_encipher('hellothere', 'clever', fillcolumnwise=True, emptycolumnwise=False)
+ 'holrhetlee'
+ >>> column_transposition_encipher('hellothere', 'clever', fillcolumnwise=False, emptycolumnwise=True)
+ 'htleehoelr'
+ >>> column_transposition_encipher('hellothere', 'clever', fillcolumnwise=False, emptycolumnwise=False)
+ 'hleolteher'
+ >>> column_transposition_encipher('hellothere', 'cleverly')
+ 'hleolthre e '
+ >>> column_transposition_encipher('hellothere', 'cleverly', fillvalue='!')
+ 'hleolthre!e!'
+ >>> column_transposition_encipher('hellothere', 'cleverly', fillvalue=lambda: '*')
+ 'hleolthre*e*'
+ """
+ transpositions = transpositions_of(keyword)
+ message += pad(len(message), len(transpositions), fillvalue)
+ if fillcolumnwise:
+ rows = every_nth(message, len(message) // len(transpositions))
+ else:
+ rows = chunks(message, len(transpositions))
+ transposed = [transpose(r, transpositions) for r in rows]
+ if emptycolumnwise:
+ return combine_every_nth(transposed)
+ else:
+ return cat(chain(*transposed))
+
+def column_transposition_decipher(message, keyword, fillvalue=' ',
+ fillcolumnwise=False,
+ emptycolumnwise=False):
+ """Deciphers using the column transposition cipher.
+ Message is padded to allow all rows to be the same length.
+
+ >>> column_transposition_decipher('hellothere', 'abcde', fillcolumnwise=True, emptycolumnwise=True)
+ 'hellothere'
+ >>> column_transposition_decipher('hlohreltee', 'abcde', fillcolumnwise=True, emptycolumnwise=False)
+ 'hellothere'
+ >>> column_transposition_decipher('htehlelroe', 'abcde', fillcolumnwise=False, emptycolumnwise=True)
+ 'hellothere'
+ >>> column_transposition_decipher('hellothere', 'abcde', fillcolumnwise=False, emptycolumnwise=False)
+ 'hellothere'
+ >>> column_transposition_decipher('heotllrehe', 'clever', fillcolumnwise=True, emptycolumnwise=True)
+ 'hellothere'
+ >>> column_transposition_decipher('holrhetlee', 'clever', fillcolumnwise=True, emptycolumnwise=False)
+ 'hellothere'
+ >>> column_transposition_decipher('htleehoelr', 'clever', fillcolumnwise=False, emptycolumnwise=True)
+ 'hellothere'
+ >>> column_transposition_decipher('hleolteher', 'clever', fillcolumnwise=False, emptycolumnwise=False)
+ 'hellothere'
+ """
+ transpositions = transpositions_of(keyword)
+ message += pad(len(message), len(transpositions), fillvalue)
+ if emptycolumnwise:
+ rows = every_nth(message, len(message) // len(transpositions))
+ else:
+ rows = chunks(message, len(transpositions))
+ untransposed = [untranspose(r, transpositions) for r in rows]
+ if fillcolumnwise:
+ return combine_every_nth(untransposed)
+ else:
+ return cat(chain(*untransposed))
+
+def scytale_encipher(message, rows, fillvalue=' '):