diff --git a/ProgrammingAssignment_1/model.ipynb b/ProgrammingAssignment_1/model.ipynb
index bd26853d28bab1cd4d591d6a326a5215636d2ff6..8cc5da3eb03ddcdfce0f7bd9950d7e1ba0070e72 100644
--- a/ProgrammingAssignment_1/model.ipynb
+++ b/ProgrammingAssignment_1/model.ipynb
@@ -82,6 +82,8 @@
     "            1D array containing test set indices\n",
     "        val_indices: ndarray\n",
     "            1D array containing validation set indices\n",
+    "        train_indices: ndarray\n",
+    "            1D array containing training set indices\n",
     "    '''\n",
     "    \n",
     "    # number of test and validation examples\n",