Issue nltk#1859: Add method definition for abstract method max in Ran…

…domProbDist and MutableProbDist

AUTHORS.md

@@ -1,4 +1,4 @@
-# Natural Language Toolkit (NLTK) Authors
+# Natural Language Toolkit (NLTK) Authors
 
 ## Original Authors
 
@@ -223,6 +223,7 @@
 - Stoytcho Stoytchev
 - Lakhdar Benzahia
 - Oleg Chislov
+- Pavan Gururaj Joshi <https://github.com/PavanGJ>
 
 ## Others whose work we've taken and included in NLTK, but who didn't directly contribute it:
 ### Contributors to the Porter Stemmer
@@ -239,4 +240,4 @@
 ### Authors of snowball arabic stemmer algorithm
 - Assem Chelli
 - Abdelkrim Aries
-- Lakhdar Benzahia
+- Lakhdar Benzahia

nltk/probability.py

@@ -603,6 +603,11 @@ def unirand(cls, samples):
 
         return dict((s, randrow[i]) for i, s in enumerate(samples))
 
+    def max(self):
+        if not hasattr(self, '_max'):
+            self._max = max((p,v) for (v,p) in self._probs.items())[1]
+        return self._max
+
     def prob(self, sample):
         return self._probs.get(sample, 0)
 
@@ -1522,6 +1527,10 @@ def __init__(self, prob_dist, samples, store_logs=True):
                 self._data[i] = prob_dist.prob(samples[i])
         self._logs = store_logs
 
+    def max(self):
+        # inherit documentation
+        return max((p,v) for (v,p) in self._sample_dict.items())[1]
+
     def samples(self):
         # inherit documentation
         return self._samples