X-Git-Url: https://git.njae.me.uk/?a=blobdiff_plain;f=cipher.py;h=2eb89f72306e30e4db99e539e36733aa792d13c4;hb=21c390a77d42729afa23844ef2f1295106bed3de;hp=e318aa46f8776fe24d9293e7d2b91def53d72663;hpb=d0a53e974970bc915d94280b5158b50f93054dc3;p=cipher-tools.git

diff --git a/cipher.py b/cipher.py
index e318aa4..2eb89f7 100644
--- a/cipher.py
+++ b/cipher.py
@@ -10,796 +10,17 @@ from language_models import *
 import pprint
 
 
-## Utility functions
-cat = ''.join
-wcat = ' '.join
-lcat = '\n'.join
-
-def pos(letter): 
-    if letter in string.ascii_lowercase:
-        return ord(letter) - ord('a')
-    elif letter in string.ascii_uppercase:
-        return ord(letter) - ord('A')
-    else:
-        return ''
-    
-def unpos(number): return chr(number % 26 + ord('a'))
-
-
-modular_division_table = [[0]*26 for _ in range(26)]
-for a in range(26):
-    for b in range(26):
-        c = (a * b) % 26
-        modular_division_table[b][c] = a
-
-
-def every_nth(text, n, fillvalue=''):
-    """Returns n strings, each of which consists of every nth character, 
-    starting with the 0th, 1st, 2nd, ... (n-1)th character
-    
-    >>> every_nth(string.ascii_lowercase, 5)
-    ['afkpuz', 'bglqv', 'chmrw', 'dinsx', 'ejoty']
-    >>> every_nth(string.ascii_lowercase, 1)
-    ['abcdefghijklmnopqrstuvwxyz']
-    >>> every_nth(string.ascii_lowercase, 26) # doctest: +NORMALIZE_WHITESPACE
-    ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 
-     'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z']
-    >>> every_nth(string.ascii_lowercase, 5, fillvalue='!')
-    ['afkpuz', 'bglqv!', 'chmrw!', 'dinsx!', 'ejoty!']
-    """
-    split_text = chunks(text, n, fillvalue)
-    return [cat(l) for l in zip_longest(*split_text, fillvalue=fillvalue)]
-
-def combine_every_nth(split_text):
-    """Reforms a text split into every_nth strings
-    
-    >>> combine_every_nth(every_nth(string.ascii_lowercase, 5))
-    'abcdefghijklmnopqrstuvwxyz'
-    >>> combine_every_nth(every_nth(string.ascii_lowercase, 1))
-    'abcdefghijklmnopqrstuvwxyz'
-    >>> combine_every_nth(every_nth(string.ascii_lowercase, 26))
-    'abcdefghijklmnopqrstuvwxyz'
-    """
-    return cat([cat(l) 
-                    for l in zip_longest(*split_text, fillvalue='')])
-
-def chunks(text, n, fillvalue=None):
-    """Split a text into chunks of n characters
-
-    >>> chunks('abcdefghi', 3)
-    ['abc', 'def', 'ghi']
-    >>> chunks('abcdefghi', 4)
-    ['abcd', 'efgh', 'i']
-    >>> chunks('abcdefghi', 4, fillvalue='!')
-    ['abcd', 'efgh', 'i!!!']
-    """
-    if fillvalue:
-        padding = fillvalue[0] * (n - len(text) % n)
-    else:
-        padding = ''
-    return [(text+padding)[i:i+n] for i in range(0, len(text), n)]
-
-def transpose(items, transposition):
-    """Moves items around according to the given transposition
-    
-    >>> transpose(['a', 'b', 'c', 'd'], (0,1,2,3))
-    ['a', 'b', 'c', 'd']
-    >>> transpose(['a', 'b', 'c', 'd'], (3,1,2,0))
-    ['d', 'b', 'c', 'a']
-    >>> transpose([10,11,12,13,14,15], (3,2,4,1,5,0))
-    [13, 12, 14, 11, 15, 10]
-    """
-    transposed = [''] * len(transposition)
-    for p, t in enumerate(transposition):
-       transposed[p] = items[t]
-    return transposed
-
-def untranspose(items, transposition):
-    """Undoes a transpose
-    
-    >>> untranspose(['a', 'b', 'c', 'd'], [0,1,2,3])
-    ['a', 'b', 'c', 'd']
-    >>> untranspose(['d', 'b', 'c', 'a'], [3,1,2,0])
-    ['a', 'b', 'c', 'd']
-    >>> untranspose([13, 12, 14, 11, 15, 10], [3,2,4,1,5,0])
-    [10, 11, 12, 13, 14, 15]
-    """
-    transposed = [''] * len(transposition)
-    for p, t in enumerate(transposition):
-       transposed[t] = items[p]
-    return transposed
-
-def deduplicate(text):
-    return list(collections.OrderedDict.fromkeys(text))
-
-
-def caesar_encipher_letter(accented_letter, shift):
-    """Encipher a letter, given a shift amount
-
-    >>> caesar_encipher_letter('a', 1)
-    'b'
-    >>> caesar_encipher_letter('a', 2)
-    'c'
-    >>> caesar_encipher_letter('b', 2)
-    'd'
-    >>> caesar_encipher_letter('x', 2)
-    'z'
-    >>> caesar_encipher_letter('y', 2)
-    'a'
-    >>> caesar_encipher_letter('z', 2)
-    'b'
-    >>> caesar_encipher_letter('z', -1)
-    'y'
-    >>> caesar_encipher_letter('a', -1)
-    'z'
-    >>> caesar_encipher_letter('A', 1)
-    'B'
-    >>> caesar_encipher_letter('é', 1)
-    'f'
-    """
-    # letter = unaccent(accented_letter)
-    # if letter in string.ascii_letters:
-    #     if letter in string.ascii_uppercase:
-    #         alphabet_start = ord('A')
-    #     else:
-    #         alphabet_start = ord('a')
-    #     return chr(((ord(letter) - alphabet_start + shift) % 26) + 
-    #                alphabet_start)
-    # else:
-    #     return letter
-
-    letter = unaccent(accented_letter)
-    if letter in string.ascii_letters:
-        cipherletter = unpos(pos(letter) + shift)
-        if letter in string.ascii_uppercase:
-            return cipherletter.upper()
-        else:
-            return cipherletter
-    else:
-        return letter
-
-def caesar_decipher_letter(letter, shift):
-    """Decipher a letter, given a shift amount
-    
-    >>> caesar_decipher_letter('b', 1)
-    'a'
-    >>> caesar_decipher_letter('b', 2)
-    'z'
-    """
-    return caesar_encipher_letter(letter, -shift)
-
-def caesar_encipher(message, shift):
-    """Encipher a message with the Caesar cipher of given shift
-    
-    >>> caesar_encipher('abc', 1)
-    'bcd'
-    >>> caesar_encipher('abc', 2)
-    'cde'
-    >>> caesar_encipher('abcxyz', 2)
-    'cdezab'
-    >>> caesar_encipher('ab cx yz', 2)
-    'cd ez ab'
-    >>> caesar_encipher('Héllo World!', 2)
-    'Jgnnq Yqtnf!'
-    """
-    enciphered = [caesar_encipher_letter(l, shift) for l in message]
-    return cat(enciphered)
-
-def caesar_decipher(message, shift):
-    """Decipher a message with the Caesar cipher of given shift
-    
-    >>> caesar_decipher('bcd', 1)
-    'abc'
-    >>> caesar_decipher('cde', 2)
-    'abc'
-    >>> caesar_decipher('cd ez ab', 2)
-    'ab cx yz'
-    >>> caesar_decipher('Jgnnq Yqtnf!', 2)
-    'Hello World!'
-    """
-    return caesar_encipher(message, -shift)
-
-def affine_encipher_letter(accented_letter, multiplier=1, adder=0, one_based=True):
-    """Encipher a letter, given a multiplier and adder
-    
-    >>> cat(affine_encipher_letter(l, 3, 5, True) \
-            for l in string.ascii_letters)
-    'hknqtwzcfiloruxadgjmpsvybeHKNQTWZCFILORUXADGJMPSVYBE'
-    >>> cat(affine_encipher_letter(l, 3, 5, False) \
-            for l in string.ascii_letters)
-    'filoruxadgjmpsvybehknqtwzcFILORUXADGJMPSVYBEHKNQTWZC'
-    """
-    # letter = unaccent(accented_letter)
-    # if letter in string.ascii_letters:
-    #     if letter in string.ascii_uppercase:
-    #         alphabet_start = ord('A')
-    #     else:
-    #         alphabet_start = ord('a')
-    #     letter_number = ord(letter) - alphabet_start
-    #     if one_based: letter_number += 1
-    #     cipher_number = (letter_number * multiplier + adder) % 26
-    #     if one_based: cipher_number -= 1
-    #     return chr(cipher_number % 26 + alphabet_start)
-    # else:
-    #     return letter
-    letter = unaccent(accented_letter)
-    if letter in string.ascii_letters:
-        letter_number = pos(letter)
-        if one_based: letter_number += 1
-        cipher_number = (letter_number * multiplier + adder) % 26
-        if one_based: cipher_number -= 1
-        if letter in string.ascii_uppercase:
-            return unpos(cipher_number).upper()
-        else:
-            return unpos(cipher_number)
-    else:
-        return letter
-
-def affine_decipher_letter(letter, multiplier=1, adder=0, one_based=True):
-    """Encipher a letter, given a multiplier and adder
-    
-    >>> cat(affine_decipher_letter(l, 3, 5, True) \
-            for l in 'hknqtwzcfiloruxadgjmpsvybeHKNQTWZCFILORUXADGJMPSVYBE')
-    'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'
-    >>> cat(affine_decipher_letter(l, 3, 5, False) \
-            for l in 'filoruxadgjmpsvybehknqtwzcFILORUXADGJMPSVYBEHKNQTWZC')
-    'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'
-    """
-    # if letter in string.ascii_letters:
-    #     if letter in string.ascii_uppercase:
-    #         alphabet_start = ord('A')
-    #     else:
-    #         alphabet_start = ord('a')
-    #     cipher_number = ord(letter) - alphabet_start
-    #     if one_based: cipher_number += 1
-    #     plaintext_number = ( 
-    #         modular_division_table[multiplier]
-    #                               [(cipher_number - adder) % 26])
-    #     if one_based: plaintext_number -= 1
-    #     return chr(plaintext_number % 26 + alphabet_start) 
-    # else:
-    #     return letter
-    if letter in string.ascii_letters:
-        cipher_number = pos(letter)
-        if one_based: cipher_number += 1
-        plaintext_number = ( 
-            modular_division_table[multiplier]
-                                  [(cipher_number - adder) % 26])
-        if one_based: plaintext_number -= 1
-        if letter in string.ascii_uppercase:
-            return unpos(plaintext_number).upper()
-        else:
-            return unpos(plaintext_number) 
-    else:
-        return letter
-
-def affine_encipher(message, multiplier=1, adder=0, one_based=True):
-    """Encipher a message
-    
-    >>> affine_encipher('hours passed during which jerico tried every ' \
-           'trick he could think of', 15, 22, True)
-    'lmyfu bkuusd dyfaxw claol psfaom jfasd snsfg jfaoe ls omytd jlaxe mh'
-    """
-    enciphered = [affine_encipher_letter(l, multiplier, adder, one_based) 
-                  for l in message]
-    return cat(enciphered)
-
-def affine_decipher(message, multiplier=1, adder=0, one_based=True):
-    """Decipher a message
-    
-    >>> affine_decipher('lmyfu bkuusd dyfaxw claol psfaom jfasd snsfg ' \
-           'jfaoe ls omytd jlaxe mh', 15, 22, True)
-    'hours passed during which jerico tried every trick he could think of'
-    """
-    enciphered = [affine_decipher_letter(l, multiplier, adder, one_based) 
-                  for l in message]
-    return cat(enciphered)
-
-
-class KeywordWrapAlphabet(Enum):
-    from_a = 1
-    from_last = 2
-    from_largest = 3
-
-
-def keyword_cipher_alphabet_of(keyword, wrap_alphabet=KeywordWrapAlphabet.from_a):
-    """Find the cipher alphabet given a keyword.
-    wrap_alphabet controls how the rest of the alphabet is added
-    after the keyword.
-
-    >>> keyword_cipher_alphabet_of('bayes')
-    'bayescdfghijklmnopqrtuvwxz'
-    >>> keyword_cipher_alphabet_of('bayes', KeywordWrapAlphabet.from_a)
-    'bayescdfghijklmnopqrtuvwxz'
-    >>> keyword_cipher_alphabet_of('bayes', KeywordWrapAlphabet.from_last)
-    'bayestuvwxzcdfghijklmnopqr'
-    >>> keyword_cipher_alphabet_of('bayes', KeywordWrapAlphabet.from_largest)
-    'bayeszcdfghijklmnopqrtuvwx'
-    """
-    if wrap_alphabet == KeywordWrapAlphabet.from_a:
-        cipher_alphabet = cat(deduplicate(sanitise(keyword) + 
-                                              string.ascii_lowercase))
-    else:
-        if wrap_alphabet == KeywordWrapAlphabet.from_last:
-            last_keyword_letter = deduplicate(sanitise(keyword))[-1]
-        else:
-            last_keyword_letter = sorted(sanitise(keyword))[-1]
-        last_keyword_position = string.ascii_lowercase.find(
-            last_keyword_letter) + 1
-        cipher_alphabet = cat(
-            deduplicate(sanitise(keyword) + 
-                        string.ascii_lowercase[last_keyword_position:] + 
-                        string.ascii_lowercase))
-    return cipher_alphabet
-
-
-def keyword_encipher(message, keyword, wrap_alphabet=KeywordWrapAlphabet.from_a):
-    """Enciphers a message with a keyword substitution cipher.
-    wrap_alphabet controls how the rest of the alphabet is added
-    after the keyword.
-    0 : from 'a'
-    1 : from the last letter in the sanitised keyword
-    2 : from the largest letter in the sanitised keyword
-
-    >>> keyword_encipher('test message', 'bayes')
-    'rsqr ksqqbds'
-    >>> keyword_encipher('test message', 'bayes', KeywordWrapAlphabet.from_a)
-    'rsqr ksqqbds'
-    >>> keyword_encipher('test message', 'bayes', KeywordWrapAlphabet.from_last)
-    'lskl dskkbus'
-    >>> keyword_encipher('test message', 'bayes', KeywordWrapAlphabet.from_largest)
-    'qspq jsppbcs'
-    """
-    cipher_alphabet = keyword_cipher_alphabet_of(keyword, wrap_alphabet)
-    cipher_translation = ''.maketrans(string.ascii_lowercase, cipher_alphabet)
-    return unaccent(message).lower().translate(cipher_translation)
-
-def keyword_decipher(message, keyword, wrap_alphabet=KeywordWrapAlphabet.from_a):
-    """Deciphers a message with a keyword substitution cipher.
-    wrap_alphabet controls how the rest of the alphabet is added
-    after the keyword.
-    0 : from 'a'
-    1 : from the last letter in the sanitised keyword
-    2 : from the largest letter in the sanitised keyword
-    
-    >>> keyword_decipher('rsqr ksqqbds', 'bayes')
-    'test message'
-    >>> keyword_decipher('rsqr ksqqbds', 'bayes', KeywordWrapAlphabet.from_a)
-    'test message'
-    >>> keyword_decipher('lskl dskkbus', 'bayes', KeywordWrapAlphabet.from_last)
-    'test message'
-    >>> keyword_decipher('qspq jsppbcs', 'bayes', KeywordWrapAlphabet.from_largest)
-    'test message'
-    """
-    cipher_alphabet = keyword_cipher_alphabet_of(keyword, wrap_alphabet)
-    cipher_translation = ''.maketrans(cipher_alphabet, string.ascii_lowercase)
-    return message.lower().translate(cipher_translation)
-
-
-def vigenere_encipher(message, keyword):
-    """Vigenere encipher
-
-    >>> vigenere_encipher('hello', 'abc')
-    'hfnlp'
-    """
-    shifts = [pos(l) 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 = [pos(l) 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
 
+from utilities import *
+from segment import *
 
-    >>> 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.
+from caesar import *
+from affine import *
+from keyword import *
+from polybius import *
+from column_transposition import *
+from railfence import *
 
-    >>> 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=' '):
-    """Enciphers using the scytale transposition cipher.
-    Message is padded with spaces to allow all rows to be the same length.
-
-    >>> scytale_encipher('thequickbrownfox', 3)
-    'tcnhkfeboqrxuo iw '
-    >>> scytale_encipher('thequickbrownfox', 4)
-    'tubnhirfecooqkwx'
-    >>> scytale_encipher('thequickbrownfox', 5)
-    'tubn hirf ecoo qkwx '
-    >>> scytale_encipher('thequickbrownfox', 6)
-    'tqcrnxhukof eibwo '
-    >>> scytale_encipher('thequickbrownfox', 7)
-    'tqcrnx hukof  eibwo  '
-    """
-    # transpositions = [i for i in range(math.ceil(len(message) / rows))]
-    # return column_transposition_encipher(message, transpositions, 
-    #     fillvalue=fillvalue, fillcolumnwise=False, emptycolumnwise=True)
-    transpositions = [i for i in range(rows)]
-    return column_transposition_encipher(message, transpositions, 
-        fillvalue=fillvalue, fillcolumnwise=True, emptycolumnwise=False)
-
-def scytale_decipher(message, rows):
-    """Deciphers using the scytale transposition cipher.
-    Assumes the message is padded so that all rows are the same length.
-    
-    >>> scytale_decipher('tcnhkfeboqrxuo iw ', 3)
-    'thequickbrownfox  '
-    >>> scytale_decipher('tubnhirfecooqkwx', 4)
-    'thequickbrownfox'
-    >>> scytale_decipher('tubn hirf ecoo qkwx ', 5)
-    'thequickbrownfox    '
-    >>> scytale_decipher('tqcrnxhukof eibwo ', 6)
-    'thequickbrownfox  '
-    >>> scytale_decipher('tqcrnx hukof  eibwo  ', 7)
-    'thequickbrownfox     '
-    """
-    # transpositions = [i for i in range(math.ceil(len(message) / rows))]
-    # return column_transposition_decipher(message, transpositions, 
-    #     fillcolumnwise=False, emptycolumnwise=True)
-    transpositions = [i for i in range(rows)]
-    return column_transposition_decipher(message, transpositions, 
-        fillcolumnwise=True, emptycolumnwise=False)
-
-
-def railfence_encipher(message, height, fillvalue=''):
-    """Railfence cipher.
-    Works by splitting the text into sections, then reading across them to
-    generate the rows in the cipher. The rows are then combined to form the
-    ciphertext.
-
-    Example: the plaintext "hellotherefriends", with a height of four, written 
-    out in the railfence as 
-       h h i
-       etere*
-       lorfns
-       l e d
-    (with the * showing the one character to finish the last section). 
-    Each 'section' is two columns, but unfolded. In the example, the first
-    section is 'hellot'.
-
-    >>> railfence_encipher('hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers', 2, fillvalue='!')
-    'hlohraateerishsslnpeefetotsigaleccpeselteevsmhatetiiaogicotxfretnrifneihr!'
-    >>> railfence_encipher('hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers', 3, fillvalue='!')
-    'horaersslpeeosglcpselteevsmhatetiiaogicotxfretnrifneihr!!lhateihsnefttiaece!'
-    >>> railfence_encipher('hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers', 5, fillvalue='!')
-    'hresleogcseeemhetaocofrnrner!!lhateihsnefttiaece!!ltvsatiigitxetifih!!oarspeslp!'
-    >>> railfence_encipher('hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers', 10, fillvalue='!')
-    'hepisehagitnr!!lernesge!!lmtocerh!!otiletap!!tseaorii!!hassfolc!!evtitffe!!rahsetec!!eixn!'
-    >>> railfence_encipher('hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers', 3)
-    'horaersslpeeosglcpselteevsmhatetiiaogicotxfretnrifneihrlhateihsnefttiaece'
-    >>> railfence_encipher('hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers', 5)
-    'hresleogcseeemhetaocofrnrnerlhateihsnefttiaeceltvsatiigitxetifihoarspeslp'
-    >>> railfence_encipher('hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers', 7)
-    'haspolsevsetgifrifrlatihnettaeelemtiocxernhorersleesgcptehaiaottneihesfic'
-    """
-    sections = chunks(message, (height - 1) * 2, fillvalue=fillvalue)
-    n_sections = len(sections)
-    # Add the top row
-    rows = [cat([s[0] for s in sections])]
-    # process the middle rows of the grid
-    for r in range(1, height-1):
-        rows += [cat([s[r:r+1] + s[height*2-r-2:height*2-r-1] for s in sections])]
-    # process the bottom row
-    rows += [cat([s[height - 1:height] for s in sections])]
-    # rows += [wcat([s[height - 1] for s in sections])]
-    return cat(rows)
-
-def railfence_decipher(message, height, fillvalue=''):
-    """Railfence decipher. 
-    Works by reconstructing the grid used to generate the ciphertext, then
-    unfolding the sections so the text can be concatenated together.
-
-    Example: given the ciphertext 'hhieterelorfnsled' and a height of 4, first
-    work out that the second row has a character missing, find the rows of the
-    grid, then split the section into its two columns.
-
-    'hhieterelorfnsled' is split into
-        h h i
-        etere
-        lorfns
-        l e d
-    (spaces added for clarity), which is stored in 'rows'. This is then split
-    into 'down_rows' and 'up_rows':
-
-    down_rows:
-       hhi
-       eee
-       lrn
-       led
-
-    up_rows:
-       tr
-       ofs
-
-    These are then zipped together (after the up_rows are reversed) to recover 
-    the plaintext.
-
-    Most of the procedure is about finding the correct lengths for each row then
-    splitting the ciphertext into those rows.
-
-    >>> railfence_decipher('hlohraateerishsslnpeefetotsigaleccpeselteevsmhatetiiaogicotxfretnrifneihr!', 2).strip('!')
-    'hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers'
-    >>> railfence_decipher('horaersslpeeosglcpselteevsmhatetiiaogicotxfretnrifneihr!!lhateihsnefttiaece!', 3).strip('!')
-    'hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers'
-    >>> railfence_decipher('hresleogcseeemhetaocofrnrner!!lhateihsnefttiaece!!ltvsatiigitxetifih!!oarspeslp!', 5).strip('!')
-    'hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers'
-    >>> railfence_decipher('hepisehagitnr!!lernesge!!lmtocerh!!otiletap!!tseaorii!!hassfolc!!evtitffe!!rahsetec!!eixn!', 10).strip('!')
-    'hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers'
-    >>> railfence_decipher('horaersslpeeosglcpselteevsmhatetiiaogicotxfretnrifneihrlhateihsnefttiaece', 3)
-    'hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers'
-    >>> railfence_decipher('hresleogcseeemhetaocofrnrnerlhateihsnefttiaeceltvsatiigitxetifihoarspeslp', 5)
-    'hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers'
-    >>> railfence_decipher('haspolsevsetgifrifrlatihnettaeelemtiocxernhorersleesgcptehaiaottneihesfic', 7)
-    'hellothereavastmeheartiesthisisalongpieceoftextfortestingrailfenceciphers'
-    """
-    # find the number and size of the sections, including how many characters
-    #   are missing for a full grid
-    n_sections = math.ceil(len(message) / ((height - 1) * 2))
-    padding_to_add = n_sections * (height - 1) * 2 - len(message)
-    # row_lengths are for the both up rows and down rows
-    row_lengths = [n_sections] * (height - 1) * 2
-    for i in range((height - 1) * 2 - 1, (height - 1) * 2 - (padding_to_add + 1), -1):
-        row_lengths[i] -= 1
-    # folded_rows are the combined row lengths in the middle of the railfence
-    folded_row_lengths = [row_lengths[0]]
-    for i in range(1, height-1):
-        folded_row_lengths += [row_lengths[i] + row_lengths[-i]]
-    folded_row_lengths += [row_lengths[height - 1]]
-    # find the rows that form the railfence grid
-    rows = []
-    row_start = 0
-    for i in folded_row_lengths:
-        rows += [message[row_start:row_start + i]]
-        row_start += i
-    # split the rows into the 'down_rows' (those that form the first column of
-    #   a section) and the 'up_rows' (those that ofrm the second column of a 
-    #   section).
-    down_rows = [rows[0]]
-    up_rows = []
-    for i in range(1, height-1):
-        down_rows += [cat([c for n, c in enumerate(rows[i]) if n % 2 == 0])]
-        up_rows += [cat([c for n, c in enumerate(rows[i]) if n % 2 == 1])]
-    down_rows += [rows[-1]]
-    up_rows.reverse()
-    return cat(c for r in zip_longest(*(down_rows + up_rows), fillvalue='') for c in r)
 
 def make_cadenus_keycolumn(doubled_letters = 'vw', start='a', reverse=False):
     """Makes the key column for a Cadenus cipher (the column down between the