some small fixes

Cryptography/README.md

@@ -3,6 +3,8 @@
 - https://www.cryptool.org/en/cryptool1-en
 
 - frequency analyses online: 
+http://www.simonsingh.net/The_Black_Chamber/hintsandtips.html
+http://www.xarg.org/tools/caesar-cipher/
 
 
 ## ROT13
@@ -21,7 +23,3 @@ In Python we can use: ```"YRIRY GJB CNFFJBEQ EBGGRA".decode(encoding="ROT13")```
 https://docs.python.org/2/library/codecs.html#codec-base-classes
 
 ---
-
-Online: 
-
-http://www.xarg.org/tools/caesar-cipher/

Cryptography/RotationCiphers/README.md

@@ -1,6 +0,0 @@
-CryptoAnalysis
-==============
-
-* Several implementations of Caesar cipher with frequency analysis.
-
-* Vinegere code.

Cryptography/RotationCiphers/caesarCipher.py

@@ -7,9 +7,7 @@ __author__ = "bt3gl"
 import string
 
 
-FREQ_ENGLISH = [0.0749, 0.0129, 0.0354, 0.0362, 0.1400, 0.0218, 0.0174, 0.0422, 0.0665, 0.0027, 0.0047, 0.0357,
-           0.0339, 0.0674, 0.0737, 0.0243, 0.0026, 0.0614, 0.0695, 0.0985, 0.0300, 0.0116, 0.0169, 0.0028,
-           0.0164, 0.0004]
+FREQ_ENGLISH = [0.0749, 0.0129, 0.0354, 0.0362, 0.1400, 0.0218, 0.0174, 0.0422, 0.0665, 0.0027, 0.0047, 0.0357,0.0339, 0.0674, 0.0737, 0.0243, 0.0026, 0.0614, 0.0695, 0.0985, 0.0300, 0.0116, 0.0169, 0.0028, 0.0164, 0.0004]
 
 
 
@@ -38,7 +36,7 @@ def frequency(msg):
     # Compute the word frequencies
     dict_freq = dict([(c,0) for c in string.lowercase])
     diff = 0.0
-    for c in msg:
+    for c in msg.lower():
         if 'a'<= c <= 'z':
             diff += 1
             dict_freq[c] += 1
@@ -50,14 +48,13 @@ def frequency(msg):
 
 def decipher(msg):
     # Decipher by frequency
-    min_delta = 1000
-    best_rotation = 0
+    min_delta, best_rotation = 20, 0.0
     freq = frequency(msg)
-    for key in range(26):
-        d = delta(freq, FREQ_ENGLISH)
+    for k in range(26):
+    	d = delta(freq[k:] + freq[:k], FREQ_ENGLISH)
         if d < min_delta:
             min_delta = d
-            best_rotation = key
+            best_rotation = k
     return cipher(msg, -best_rotation)
 
 
@@ -74,12 +71,17 @@ def decipher_simple(msg):
 
 if __name__ == '__main__':
 
+    # creating a cipher
     key = 13
     text = 'hacker school is awesome!'
-    cip = cipher(text, key)
-    dec = decipher(cip)
+    cipe = cipher(text, key)
+    print "Cipher: " + cipe
+  
+    # decyphering
+    with open('cipher.txt', 'r') as f:	
+	cip = f.readlines()
+	cip = cip[0].strip()
+        cipe =  decipher(cip)    	  	
+    	print "Decipher: " + cipe
 
-    print "Cipher: " + cip
-    print "Decipher: " + dec
-
-    assert(text == dec)
+