Fix bug of binarizing rating values in Reader (#211)

Author: tqtg

cornac/data/reader.py

@@ -116,7 +116,8 @@ def __init__(self, user_set=None, item_set=None, min_user_freq=1, min_item_freq=
 
     def filter(self, tuples):
         if self.bin_threshold is not None:
-            tuples = [tup for tup in tuples if tup[2] >= self.bin_threshold]
+            def binarize(t): t = list(t); t[2] = 1; return tuple(t)
+            tuples = [binarize(t) for t in tuples if t[2] >= self.bin_threshold]
 
         if self.users is not None:
             if isinstance(self.users, list):

tests/cornac/data/test_reader.py

@@ -50,7 +50,9 @@ def test_read_uir(self):
 
     def test_filter(self):
         reader = Reader(bin_threshold=4.0)
-        self.assertEqual(len(reader.read(self.data_file)), 8)
+        data = reader.read(self.data_file)
+        self.assertEqual(len(data), 8)
+        self.assertListEqual([x[2] for x in data], [1] * len(data))
 
         reader = Reader(min_user_freq=2)
         self.assertEqual(len(reader.read(self.data_file)), 0)