Another update from ingydotnet^djgoku

Task/Levenshtein-distance/Python/levenshtein-distance-1.py

@@ -1,4 +1,4 @@
-def levenshteinDistance(s1,s2):
+def minimumEditDistance(s1,s2):
     if len(s1) > len(s2):
         s1,s2 = s2,s1
     distances = range(len(s1) + 1)
@@ -14,5 +14,5 @@ def levenshteinDistance(s1,s2):
         distances = newDistances
     return distances[-1]
 
-print(levenshteinDistance("kitten","sitting"))
-print(levenshteinDistance("rosettacode","raisethysword"))
+print(minimumEditDistance("kitten","sitting"))
+print(minimumEditDistance("rosettacode","raisethysword"))

Task/Levenshtein-distance/Python/levenshtein-distance-2.py

@@ -1,13 +1,23 @@
->>> from functools import lru_cache
->>> @lru_cache(maxsize=4095)
-def ld(s, t):
-	if not s: return len(t)
-	if not t: return len(s)
-	if s[0] == t[0]: return ld(s[1:], t[1:])
-	l1 = ld(s, t[1:])
-	l2 = ld(s[1:], t)
-	l3 = ld(s[1:], t[1:])
-	return 1 + min(l1, l2, l3)
+def levenshteinDistance(str1, str2):
+    m = len(str1)
+    n = len(str2)
+    lensum = float(m + n)
+    d = []
+    for i in range(m+1):
+        d.append([i])
+    del d[0][0]
+    for j in range(n+1):
+        d[0].append(j)
+    for j in range(1,n+1):
+        for i in range(1,m+1):
+            if str1[i-1] == str2[j-1]:
+                d[i].insert(j,d[i-1][j-1])
+            else:
+                minimum = min(d[i-1][j]+1, d[i][j-1]+1, d[i-1][j-1]+2)
+                d[i].insert(j, minimum)
+    ldist = d[-1][-1]
+    ratio = (lensum - ldist)/lensum
+    return {'distance':ldist, 'ratio':ratio}
 
->>> print( ld("kitten","sitting"),ld("rosettacode","raisethysword") )
-3 8
+print(levenshteinDistance("kitten","sitting"))
+print(levenshteinDistance("rosettacode","raisethysword"))

Task/Levenshtein-distance/Python/levenshtein-distance-3.py

@@ -0,0 +1,13 @@
+>>> from functools import lru_cache
+>>> @lru_cache(maxsize=4095)
+def ld(s, t):
+	if not s: return len(t)
+	if not t: return len(s)
+	if s[0] == t[0]: return ld(s[1:], t[1:])
+	l1 = ld(s, t[1:])
+	l2 = ld(s[1:], t)
+	l3 = ld(s[1:], t[1:])
+	return 1 + min(l1, l2, l3)
+
+>>> print( ld("kitten","sitting"),ld("rosettacode","raisethysword") )
+3 8