1 static char help[] = "Demonstrates call PETSc first and then Trilinos in the same program.\n\n"; 2 3 /* 4 Example obtained from: http://trilinos.org/docs/dev/packages/tpetra/doc/html/Tpetra_Lesson01.html 5 */ 6 7 #include <petscsys.h> 8 #include <Teuchos_DefaultMpiComm.hpp> // wrapper for MPI_Comm 9 #include <Tpetra_Version.hpp> // Tpetra version string 10 11 // Do something with the given communicator. In this case, we just 12 // print Tpetra's version to stdout on Process 0 in the given 13 // communicator. 14 void exampleRoutine(const Teuchos::RCP<const Teuchos::Comm<int>> &comm) 15 { 16 if (comm->getRank() == 0) { 17 // On (MPI) Process 0, print out the Tpetra software version. 18 std::cout << Tpetra::version() << std::endl << std::endl; 19 } 20 } 21 22 int main(int argc, char **argv) 23 { 24 // These "using" declarations make the code more concise, in that 25 // you don't have to write the namespace along with the class or 26 // object name. This is especially helpful with commonly used 27 // things like std::endl or Teuchos::RCP. 28 using std::cout; 29 using std::endl; 30 using Teuchos::Comm; 31 using Teuchos::MpiComm; 32 using Teuchos::RCP; 33 using Teuchos::rcp; 34 35 /* 36 Every PETSc routine should begin with the PetscInitialize() routine. 37 argc, argv - These command line arguments are taken to extract the options 38 supplied to PETSc and options supplied to MPI. 39 help - When PETSc executable is invoked with the option -help, 40 it prints the various options that can be applied at 41 runtime. The user can use the "help" variable place 42 additional help messages in this printout. 43 */ 44 PetscFunctionBeginUser; 45 PetscCall(PetscInitialize(&argc, &argv, (char *)0, help)); 46 RCP<const Comm<int>> comm(new MpiComm<int>(PETSC_COMM_WORLD)); 47 // Get my process' rank, and the total number of processes. 48 // Equivalent to MPI_Comm_rank resp. MPI_Comm_size. 49 const int myRank = comm->getRank(); 50 const int size = comm->getSize(); 51 if (myRank == 0) cout << "Total number of processes: " << size << endl; 52 // Do something with the new communicator. 53 exampleRoutine(comm); 54 // This tells the Trilinos test framework that the test passed. 55 if (myRank == 0) cout << "End Result: TEST PASSED" << endl; 56 57 PetscCall(PetscFinalize()); 58 return 0; 59 } 60 61 /*TEST 62 63 build: 64 requires: trilinos 65 66 test: 67 nsize: 3 68 filter: grep -v "Tpetra in Trilinos" 69 70 TEST*/ 71