From: Neil Smith <neil.git@njae.me.uk>
Date: Thu, 3 Oct 2013 19:34:21 +0000 (+0100)
Subject: Can now do frequency analysis
X-Git-Url: https://git.njae.me.uk/?a=commitdiff_plain;h=e6aea9194297e503e6b2887f1756ce5dc4d6f078;p=cipher-tools.git

Can now do frequency analysis
---

diff --git a/cipher.py b/cipher.py
index f938f36..c4b28ba 100644
--- a/cipher.py
+++ b/cipher.py
@@ -1,4 +1,5 @@
 import string
+import collections
 
 
 def caesar_cipher_letter(letter, shift):
@@ -21,3 +22,11 @@ def caesar_cipher_message(message, shift):
 
 def caesar_decipher_message(message, shift):
     return caesar_cipher_message(message, -shift)
+
+def letter_frequencies(message):
+    frequencies = collections.defaultdict(int)
+    for letter in message: 
+        if letter in  string.ascii_letters:
+            frequencies[letter.lower()]+=1
+    return frequencies
+