Merge pull request #921 from Danushka2/master

Levenshtein distance between two words

Author: geekcomputers

levenshtein_distance.py

@@ -0,0 +1,52 @@
+	
+def levenshtein_dis(wordA, wordB):
+    
+    wordA = wordA.lower()                       #making the wordA lower case
+    wordB = wordB.lower()                       #making the wordB lower case
+
+
+    #get the length of the words and defining the variables
+    length_A = len(wordA)
+    length_B = len(wordB)
+    max_len = 0
+    diff = 0
+    distances = []
+    distance = 0
+
+
+    #check the difference of the word to decide how many letter should be delete or add 
+    #also store that value in the 'diff' variable and get the max length of the user given words
+    if length_A > length_B:
+        diff =  length_A - length_B
+        max_len = length_A
+    elif length_A < length_B:
+        diff = length_B - length_A
+        max_len = length_B
+    else:
+        diff = 0
+        max_len = length_A
+
+    
+    #starting from the front of the words and compare the letters of the both user given words
+    for x in range(max_len-diff):
+        if wordA[x] != wordB[x]:
+            distance += 1
+            
+    #add the 'distance' value to the 'distances' array
+    distances.append(distance)
+    distance = 0
+
+    #starting from the back of the words and compare the letters of the both user given words
+    for x in range(max_len-diff):
+        if wordA[-(x+1)] != wordB[-(x+1)]:
+            distance += 1
+
+    #add the 'distance' value to the 'distances' array
+    distances.append(distance)
+
+    #get the minimun value of the 'distances' array and add it with the 'diff' values and 
+    #store them in the 'diff' variable
+    diff = diff + min(distances)
+
+    #return the value
+    return diff