Fix issue jwyang#452 for PyTorch 0.4.0

Author: benedictflorance

lib/roi_data_layer/roibatchLoader.py

@@ -51,7 +51,7 @@ def __init__(self, roidb, ratio_list, ratio_index, batch_size, num_classes, trai
             # for ratio cross 1, we make it to be 1.
             target_ratio = 1
 
-        self.ratio_list_batch[left_idx:(right_idx+1)] = target_ratio
+        self.ratio_list_batch[left_idx:(right_idx+1)] = torch.tensor(target_ratio.astype(np.float64)) # trainset ratio list ,each batch is same number
 
 
   def __getitem__(self, index):