Remove duplicated lines (#301)

Author: eigenvivek

diffdrr/drr.py

@@ -66,11 +66,6 @@ def __init__(
         # Initialize the volume and world geometry
         self.subject = subject
         self.volume = subject.volume.data.squeeze()
-        self.register_buffer(
-            "density",
-            subject.density.data.squeeze(),
-            persistent=persistent,
-        )
         self.register_buffer(
             "_affine",
             torch.as_tensor(subject.volume.affine, dtype=torch.float32).unsqueeze(0),

notebooks/api/00_drr.ipynb

@@ -162,11 +162,6 @@
     "        self.subject = subject\n",
     "        self.volume = subject.volume.data.squeeze()\n",
     "        self.register_buffer(\n",
-    "            \"density\",\n",
-    "            subject.density.data.squeeze(),\n",
-    "            persistent=persistent,\n",
-    "        )\n",
-    "        self.register_buffer(\n",
     "            \"_affine\",\n",
     "            torch.as_tensor(subject.volume.affine, dtype=torch.float32).unsqueeze(0),\n",
     "            persistent=persistent,\n",