Fix doc

cpp/include/raft/neighbors/ivf_flat.cuh

@@ -66,9 +66,9 @@ namespace detail = raft::spatial::knn::ivf_flat::detail;
  * @return the constructed ivf-flat index
  */
 template <typename T, typename IdxT>
-auto build(raft::device_resources const& handle,
-           const index_params& params,
-           raft::device_matrix_view<const T, IdxT, row_major> dataset) -> index<T, IdxT>
+index<T, IdxT> build(raft::device_resources const& handle,
+                     const index_params& params,
+                     raft::device_matrix_view<const T, IdxT, row_major> dataset)
 {
   IdxT n_rows = dataset.extent(0);
   IdxT dim    = dataset.extent(1);
@@ -232,7 +232,7 @@ void search(raft::device_resources const& handle,
                         handle.get_workspace_resource());
 }
 
-/** @} */
+/** @} */  // end group ivf_flat
 
 /**
  * @brief Build the index from the dataset for efficient search.
@@ -276,8 +276,6 @@ auto build(raft::device_resources const& handle,
   return detail::build(handle, params, dataset, n_rows, dim);
 }
 
-/** @} */  // end group ivf_flat
-
 /**
  * @brief Build a new index containing the data of the original plus new extra vectors.
  *

cpp/include/raft/neighbors/ivf_pq.cuh

@@ -52,9 +52,9 @@ namespace raft::neighbors::ivf_pq {
  * @return the constructed ivf-pq index
  */
 template <typename T, typename IdxT = uint32_t>
-auto build(raft::device_resources const& handle,
-           const index_params& params,
-           raft::device_matrix_view<const T, IdxT, row_major> dataset) -> index<IdxT>
+index<IdxT> build(raft::device_resources const& handle,
+                  const index_params& params,
+                  raft::device_matrix_view<const T, IdxT, row_major> dataset)
 {
   IdxT n_rows = dataset.extent(0);
   IdxT dim    = dataset.extent(1);
@@ -284,7 +284,6 @@ auto extend(raft::device_resources const& handle,
  * @param[in] new_indices a device/host pointer to a vector of indices [n_rows].
  *    If the original index is empty (`index.size() == 0`), you can pass `nullptr`
  *    here to imply a continuous range `[0...n_rows)`.
- * @param[inout] idx
  * @param n_rows the number of samples
  */
 template <typename T, typename IdxT>

cpp/include/raft/neighbors/ivf_pq_serialize.cuh

@@ -47,7 +47,6 @@ namespace raft::neighbors::ivf_pq {
  * @param[in] os output stream
  * @param[in] index IVF-PQ index
  *
- * @return raft::neighbors::ivf_pq::index<IdxT>
  */
 template <typename IdxT>
 void serialize(raft::device_resources const& handle, std::ostream& os, const index<IdxT>& index)
@@ -77,7 +76,6 @@ void serialize(raft::device_resources const& handle, std::ostream& os, const ind
  * @param[in] filename the file name for saving the index
  * @param[in] index IVF-PQ index
  *
- * @return raft::neighbors::ivf_pq::index<IdxT>
  */
 template <typename IdxT>
 void serialize(raft::device_resources const& handle,