Function XGDMatrixSliceDMatrixEx

src/c_api/c_api.cc:601–612

}

XGB_DLL int XGDMatrixSliceDMatrixEx(DMatrixHandle handle, const int *idxset, xgboost::bst_ulong len,
                                    DMatrixHandle *out, int allow_groups) {
  API_BEGIN();
  CHECK_HANDLE();
  if (!allow_groups) {
    CHECK_EQ(static_cast<std::shared_ptr<DMatrix> *>(handle)->get()->Info().group_ptr_.size(), 0U)
        << "slice does not support group structure";
  }
  DMatrix *dmat = static_cast<std::shared_ptr<DMatrix> *>(handle)->get();
  *out = new std::shared_ptr<DMatrix>(dmat->Slice({idxset, static_cast<std::size_t>(len)}));
  API_END();
}

XGB_DLL int XGDMatrixFree(DMatrixHandle handle) {
  API_BEGIN();