added at:: namespace

Author: rusty1s

cpu/grid.cpp

@@ -8,8 +8,8 @@ at::Tensor grid(at::Tensor pos, at::Tensor size, at::Tensor start,
   num_voxels = num_voxels.cumprod(0);
 
   num_voxels = at::cat({at::ones(1, num_voxels.options()), num_voxels}, 0);
-  auto index = empty(size.size(0), num_voxels.options());
-  arange_out(index, size.size(0));
+  auto index = at::empty(size.size(0), num_voxels.options());
+  at::arange_out(index, size.size(0));
   num_voxels = num_voxels.index_select(0, index);
 
   auto cluster = (pos / size.view({1, -1})).toType(at::kLong);