[doc] install cpu version by default in notebooks (#7186)

notebooks/stochastic_training/link_prediction.ipynb

@@ -43,10 +43,11 @@
         "os.environ['TORCH'] = torch.__version__\n",
         "os.environ['DGLBACKEND'] = \"pytorch\"\n",
         "\n",
-        "# Install the CUDA version. If you want to install CPU version, please\n",
-        "# refer to https://www.dgl.ai/pages/start.html.\n",
-        "device = torch.device(\"cuda\")\n",
-        "!pip install --pre dgl -f https://data.dgl.ai/wheels-test/cu121/repo.html\n",
+        "# Install the CPU version in default. If you want to install CUDA version,\n",
+        "# please refer to https://www.dgl.ai/pages/start.html and change runtime type\n",
+        "# accordingly.\n",
+        "device = torch.device(\"cpu\")\n",
+        "!pip install --pre dgl -f https://data.dgl.ai/wheels-test/repo.html\n",
         "\n",
         "try:\n",
         "    import dgl\n",
@@ -348,8 +349,7 @@
   "metadata": {
     "colab": {
       "private_outputs": true,
-      "provenance": [],
-      "gpuType": "T4"
+      "provenance": []
     },
     "kernelspec": {
       "display_name": "Python 3",
@@ -366,8 +366,7 @@
       "nbconvert_exporter": "python",
       "pygments_lexer": "ipython3",
       "version": "3.10.12"
-    },
-    "accelerator": "GPU"
+    }
   },
   "nbformat": 4,
   "nbformat_minor": 0

notebooks/stochastic_training/node_classification.ipynb

@@ -44,10 +44,11 @@
         "os.environ['TORCH'] = torch.__version__\n",
         "os.environ['DGLBACKEND'] = \"pytorch\"\n",
         "\n",
-        "# Install the CUDA version. If you want to install CPU version, please\n",
-        "# refer to https://www.dgl.ai/pages/start.html.\n",
-        "device = torch.device(\"cuda\")\n",
-        "!pip install --pre dgl -f https://data.dgl.ai/wheels-test/cu121/repo.html\n",
+        "# Install the CPU version in default. If you want to install CUDA version,\n",
+        "# please refer to https://www.dgl.ai/pages/start.html and change runtime type\n",
+        "# accordingly.\n",
+        "device = torch.device(\"cpu\")\n",
+        "!pip install --pre dgl -f https://data.dgl.ai/wheels-test/repo.html\n",
         "\n",
         "try:\n",
         "    import dgl\n",
@@ -351,9 +352,7 @@
     }
   ],
   "metadata": {
-    "accelerator": "GPU",
     "colab": {
-      "gpuType": "T4",
       "private_outputs": true,
       "provenance": []
     },