diff --git a/deepxde/data/quadruple.py b/deepxde/data/quadruple.py
index 2e9fc0ee4..efbe91767 100644
--- a/deepxde/data/quadruple.py
+++ b/deepxde/data/quadruple.py
@@ -94,7 +94,7 @@ def train_next_batch(self, batch_size=None):
             self.train_x[0][indices_branch],
             self.train_x[1][indices_branch],
             self.train_x[2][indices_trunk],
-        ), self.train_y[indices_branch, indices_trunk]
+        ), self.train_y[indices_branch][:, indices_trunk]
 
     def test(self):
         return self.test_x, self.test_y