Update model.py

prevent xrange error: float cannot be interpreted as an integer

Author: petcarerx

model.py

@@ -198,7 +198,7 @@ def train(self, config):
         np.random.shuffle(self.data)
         batch_idxs = min(len(self.data), config.train_size) // config.batch_size
 
-      for idx in xrange(0, batch_idxs):
+      for idx in xrange(0, int(batch_idxs)):
         if config.dataset == 'mnist':
           batch_images = self.data_X[idx*config.batch_size:(idx+1)*config.batch_size]
           batch_labels = self.data_y[idx*config.batch_size:(idx+1)*config.batch_size]