Merge pull request #534 from 2017pxy/master

FIX: fix bugs in set_distribution in sampler.

recbole/sampler/sampler.py

@@ -33,15 +33,24 @@ class AbstractSampler(object):
         used_ids (numpy.ndarray): The result of :meth:`get_used_ids`.
     """
     def __init__(self, distribution):
-        self.distribution = distribution
+        self.distribution = None
+        self.set_distribution(distribution)
+        self.used_ids = self.get_used_ids()
 
+    def set_distribution(self, distribution):
+        """Set the distribution of sampler.
+            
+        Args:
+            distribution (str): Distribution of the negative items.
+        """
+        if self.distribution == distribution:
+            return
+        self.distribution = distribution
         self.random_list = self.get_random_list()
         random.shuffle(self.random_list)
         self.random_pr = 0
         self.random_list_length = len(self.random_list)
 
-        self.used_ids = self.get_used_ids()
-
     def get_random_list(self):
         """
         Returns:
@@ -155,12 +164,6 @@ def get_used_ids(self):
             last = used_item_id[phase] = cur
         return used_item_id
 
-    def set_distribution(self, distribution):
-        if self.distribution == distribution:
-            return
-        self.distribution = distribution
-        self.random_list = self.get_random_list()
-
     def set_phase(self, phase):
         """Get the sampler of corresponding phase.
 
@@ -301,12 +304,6 @@ def get_random_list(self):
         else:
             raise NotImplementedError('Distribution [{}] has not been implemented'.format(self.distribution))
 
-    def set_distribution(self, distribution):
-        if self.distribution == distribution:
-            return
-        self.distribution = distribution
-        self.random_list = self.get_random_list()
-
     def get_used_ids(self):
         """
         Returns: