Tpetra_RowGraph_def.hpp

// @HEADER
// *****************************************************************************
//          Tpetra: Templated Linear Algebra Services Package
//
// Copyright 2008 NTESS and the Tpetra contributors.
// SPDX-License-Identifier: BSD-3-Clause
// *****************************************************************************
// @HEADER

#ifndef TPETRA_ROWGRAPH_DEF_HPP
#define TPETRA_ROWGRAPH_DEF_HPP

namespace Tpetra {
template <class LocalOrdinal, class GlobalOrdinal, class Node>
void RowGraph<LocalOrdinal, GlobalOrdinal, Node>::
    pack(const Teuchos::ArrayView<const LocalOrdinal>& exportLIDs,
         Teuchos::Array<GlobalOrdinal>& exports,
         const Teuchos::ArrayView<size_t>& numPacketsPerLID,
         size_t& constantNumPackets) const {
  using Teuchos::Array;
  typedef LocalOrdinal LO;
  typedef GlobalOrdinal GO;
  typedef Map<LO, GO, Node> map_type;
  const char tfecfFuncName[] = "packAndPrepare";

  TEUCHOS_TEST_FOR_EXCEPTION_CLASS_FUNC(
      exportLIDs.size() != numPacketsPerLID.size(), std::runtime_error,
      ": exportLIDs and numPacketsPerLID must have the same size.");

  const map_type& srcMap = *(this->getRowMap());
  constantNumPackets     = 0;

  // Set numPacketsPerLID[i] to the number of entries owned by the
  // calling process in (local) row exportLIDs[i] of the graph, that
  // the caller wants us to send out.  Compute the total number of
  // packets (that is, entries) owned by this process in all the
  // rows that the caller wants us to send out.
  size_t totalNumPackets = 0;
  nonconst_global_inds_host_view_type row;
  for (LO i = 0; i < exportLIDs.size(); ++i) {
    const GO GID        = srcMap.getGlobalElement(exportLIDs[i]);
    size_t row_length   = this->getNumEntriesInGlobalRow(GID);
    numPacketsPerLID[i] = row_length;
    totalNumPackets += row_length;
  }

  exports.resize(totalNumPackets);

  // Loop again over the rows to export, and pack rows of indices
  // into the output buffer.
  size_t exportsOffset = 0;
  for (LO i = 0; i < exportLIDs.size(); ++i) {
    const GO GID      = srcMap.getGlobalElement(exportLIDs[i]);
    size_t row_length = this->getNumEntriesInGlobalRow(GID);
    Kokkos::resize(row, row_length);
    size_t check_row_length = 0;
    this->getGlobalRowCopy(GID, row, check_row_length);

    for (size_t j = 0; j < row_length; ++j) {
      exports[exportsOffset + j] = row[j];
    }
    exportsOffset += row.extent(0);
  }
}

}  // namespace Tpetra

//
// Explicit instantiation macro
//
// Must be expanded from within the Tpetra namespace!
//

#define TPETRA_ROWGRAPH_INSTANT(LO, GO, NODE) \
  template class RowGraph<LO, GO, NODE>;

#endif  // TPETRA_ROWGRAPH_DEF_HPP