Anagrams/Deranged anagrams

Two or more words are said to be anagrams if they have the same characters, but in a different order. By analogy with derangements we define a deranged anagram as two words with the same characters, but in which the same character does not appear in the same position in both words.

Anagrams/Deranged anagrams is a draft programming task. It is not yet considered ready to be promoted as a complete task, for reasons that should be found in its talk page.

The task is to use the word list at http://www.puzzlers.org/pub/wordlists/unixdict.txt to find and show the longest deranged anagram.

Python

<lang python>import urllib.request from collections import defaultdict from itertools import combinations

def getwords(url='http://www.puzzlers.org/pub/wordlists/unixdict.txt'):

   return list(set(urllib.request.urlopen(url).read().decode().split()))

def find_anagrams(words):

   anagram = defaultdict(list) # map sorted chars to anagrams
   for word in words:
       anagram[tuple(sorted(word))].append( word )
   return dict((key, words) for key, words in anagram.items()
               if len(words) > 1)

def is_deranged(words):

   'returns pairs of words that have no character in the same position'
   return [ (word1, word2)
            for word1,word2 in combinations(words, 2)
            if all(ch1 != ch2 for ch1, ch2 in zip(word1, word2)) ]

def largest_deranged_ana(anagrams):

   ordered_anagrams = sorted(anagrams.items(),
                             key=lambda x:(-len(x[0]), x[0]))
   for _, words in ordered_anagrams:
       deranged_pairs = is_deranged(words)
       if deranged_pairs:
           return deranged_pairs
   return []

if __name__ == '__main__':

   words = getwords('http://www.puzzlers.org/pub/wordlists/unixdict.txt')
   print("Word count:", len(words))

   anagrams = find_anagrams(words)
   print("Anagram count:", len(anagrams),"\n")

   print("Longest anagrams with no characters in the same position:")
   print('  ' + '\n  '.join(', '.join(pairs)
                            for pairs in largest_deranged_ana(anagrams)))</lang>

Sample output

Word count: 25104
Anagram count: 1303 

Longest anagrams with no characters in the same position:
  excitation, intoxicate