Moving to a different machine

[cipher-tools.git] / cipher.py

diff --git a/cipher.py b/cipher.py
index 7feaedf90fd289b9fda1da60f0dea9565e1108d1..6ef01c325d81a7055760d924c400f86b8b718340 100644 (file)
--- a/cipher.py
+++ b/cipher.py
@@ -1,7 +1,8 @@
 import string
 import collections
 import logging
 import string
 import collections
 import logging

-from itertools import zip_longest, cycle
+from itertools import zip_longest, cycle, chain
+from counts import *

 
 
 logger = logging.getLogger(__name__)
 
 
 logger = logging.getLogger(__name__)


@@ -11,6 +12,19 @@ logger.setLevel(logging.WARNING)
 #logger.setLevel(logging.DEBUG)
 
 
 #logger.setLevel(logging.DEBUG)
 
 

+english_counts = collections.defaultdict(int)
+with open('count_1l.txt', 'r') as f:
+    for line in f:
+        (letter, count) = line.split("\t")
+        english_counts[letter] = int(count)
+normalised_english_counts = norms.normalise(english_counts)
+
+choices, weights = zip(*weighted_choices)
+cumdist = list(itertools.accumulate(weights))
+x = random.random() * cumdist[-1]
+choices[bisect.bisect(cumdist, x)]
+
+

 modular_division_table = [[0]*26 for x in range(26)]
 for a in range(26):
     for b in range(26):
 modular_division_table = [[0]*26 for x in range(26)]
 for a in range(26):
     for b in range(26):


@@ -237,8 +251,9 @@ def affine_decipher_letter(letter, multiplier=1, adder=0, one_based=True):
             alphabet_start = ord('a')
         cipher_number = ord(letter) - alphabet_start
         if one_based: cipher_number += 1
             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] )
+        plaintext_number = ( 
+            modular_division_table[multiplier]
+                                  [(cipher_number - adder) % 26] )

         if one_based: plaintext_number -= 1
         return chr(plaintext_number % 26 + alphabet_start) 
     else:
         if one_based: plaintext_number -= 1
         return chr(plaintext_number % 26 + alphabet_start) 
     else:


@@ -407,8 +422,20 @@ def transpositions_of(keyword):
         transpositions = tuple(key.index(l) for l in sorted(key))
         return transpositions
 
         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=' ', 
 def column_transposition_encipher(message, keyword, fillvalue=' ', 

-      columnwise=False):
+      fillcolumnwise=False,
+      emptycolumnwise=False):

     """Enciphers using the column transposition cipher.
     Message is padded to allow all rows to be the same length.
 
     """Enciphers using the column transposition cipher.
     Message is padded to allow all rows to be the same length.
 


@@ -420,12 +447,17 @@ def column_transposition_encipher(message, keyword, fillvalue=' ',
     'htleehoelr'
     """
     transpositions = transpositions_of(keyword)
     'htleehoelr'
     """
     transpositions = transpositions_of(keyword)

+    message += pad(len(message), len(transpositions), fillvalue)
+    if fillcolumnwise:
+        rows = every_nth(message, len(transpositions))
+    else:
+        rows = chunks(mesage, len(transpositions))

     columns = every_nth(message, len(transpositions), fillvalue=fillvalue)
     columns = every_nth(message, len(transpositions), fillvalue=fillvalue)

-    transposed_columns = transpose(columns, transpositions)
-    if columnwise:
-        return ''.join(transposed_columns)
+    transposed = [transpose(r, transpositions) for r in rows]
+    if emptycolumnwise:
+        return combine_every_nth(transposed)

     else:
     else:

-        return combine_every_nth(transposed_columns)
+        return ''.join(chain(*transposed))

 
 def column_transposition_decipher(message, keyword, fillvalue=' ', 
       columnwise=False):
 
 def column_transposition_decipher(message, keyword, fillvalue=' ', 
       columnwise=False):