Actual source code: ex45.cxx
1: static char help[] = "Demonstrates call PETSc first and then Trilinos in the same program.\n\n";
3: /*
4: Example obtained from: http://trilinos.org/docs/dev/packages/tpetra/doc/html/Tpetra_Lesson01.html
5: */
7: #include <petscsys.h>
8: #include <Teuchos_DefaultMpiComm.hpp> // wrapper for MPI_Comm
9: #include <Tpetra_Version.hpp> // Tpetra version string
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: }
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;
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, nullptr, 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;
57: PetscCall(PetscFinalize());
58: return 0;
59: }
61: /*TEST
63: build:
64: requires: trilinos
66: test:
67: nsize: 3
68: filter: grep -v "Tpetra in Trilinos"
70: TEST*/