Rearranged files, added import paths

[cipher-tools.git] / caesar.py

diff --git a/caesar.py b/caesar.py
deleted file mode 100644 (file)
index 4d9a722..0000000
--- a/caesar.py
+++ /dev/null
@@ -1,120 +0,0 @@
-from utilities import *
-from language_models import *
-from logger import logger
-
-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 caesar_break(message, fitness=Pletters):
-    """Breaks a Caesar cipher using frequency analysis
-
-    >>> caesar_break('ibxcsyorsaqcheyklxivoexlevmrimwxsfiqevvmihrsasrxliwyrh' \
-          'ecjsppsamrkwleppfmergefifvmhixscsymjcsyqeoixlm') # doctest: +ELLIPSIS
-    (4, -130.849989015...)
-    >>> caesar_break('wxwmaxdgheetgwuxztgptedbgznitgwwhpguxyhkxbmhvvtlbhgtee' \
-          'raxlmhiixweblmxgxwmhmaxybkbgztgwztsxwbgmxgmert') # doctest: +ELLIPSIS
-    (19, -128.82410410...)
-    >>> caesar_break('yltbbqnqnzvguvaxurorgenafsbezqvagbnornfgsbevpnaabjurer' \
-          'svaquvzyvxrnznazlybequrvfohgriraabjtbaruraprur') # doctest: +ELLIPSIS
-    (13, -126.25403935...)
-    """
-    sanitised_message = sanitise(message)
-    best_shift = 0
-    best_fit = float('-inf')
-    for shift in range(26):
-        plaintext = caesar_decipher(sanitised_message, shift)
-        fit = fitness(plaintext)
-        logger.debug('Caesar break attempt using key {0} gives fit of {1} '
-                     'and decrypt starting: {2}'.format(shift, fit,
-                                                        plaintext[:50]))
-        if fit > best_fit:
-            best_fit = fit
-            best_shift = shift
-    logger.info('Caesar break best fit: key {0} gives fit of {1} and '
-                'decrypt starting: {2}'.format(best_shift, best_fit, 
-                    caesar_decipher(sanitised_message, best_shift)[:50]))
-    return best_shift, best_fit