xref: /petsc/src/sys/tests/ex45.cxx (revision c4762a1b19cd2af06abeed90e8f9d34fb975dd94)
1*c4762a1bSJed Brown 
2*c4762a1bSJed Brown static char help[] = "Demonstrates call PETSc first and then Trilinos in the same program.\n\n";
3*c4762a1bSJed Brown 
4*c4762a1bSJed Brown /*T
5*c4762a1bSJed Brown    Concepts: introduction to PETSc^Trilinos
6*c4762a1bSJed Brown    Processors: n
7*c4762a1bSJed Brown 
8*c4762a1bSJed Brown    Example obtained from: http://trilinos.org/docs/dev/packages/tpetra/doc/html/Tpetra_Lesson01.html
9*c4762a1bSJed Brown T*/
10*c4762a1bSJed Brown 
11*c4762a1bSJed Brown 
12*c4762a1bSJed Brown 
13*c4762a1bSJed Brown #include <petscsys.h>
14*c4762a1bSJed Brown #include <Teuchos_DefaultMpiComm.hpp> // wrapper for MPI_Comm
15*c4762a1bSJed Brown #include <Tpetra_Version.hpp> // Tpetra version string
16*c4762a1bSJed Brown 
17*c4762a1bSJed Brown // Do something with the given communicator.  In this case, we just
18*c4762a1bSJed Brown // print Tpetra's version to stdout on Process 0 in the given
19*c4762a1bSJed Brown // communicator.
20*c4762a1bSJed Brown void
21*c4762a1bSJed Brown exampleRoutine (const Teuchos::RCP<const Teuchos::Comm<int> >& comm)
22*c4762a1bSJed Brown {
23*c4762a1bSJed Brown   if (comm->getRank () == 0) {
24*c4762a1bSJed Brown     // On (MPI) Process 0, print out the Tpetra software version.
25*c4762a1bSJed Brown     std::cout << Tpetra::version () << std::endl << std::endl;
26*c4762a1bSJed Brown   }
27*c4762a1bSJed Brown }
28*c4762a1bSJed Brown 
29*c4762a1bSJed Brown int main(int argc,char **argv)
30*c4762a1bSJed Brown {
31*c4762a1bSJed Brown   PetscErrorCode ierr;
32*c4762a1bSJed Brown   // These "using" declarations make the code more concise, in that
33*c4762a1bSJed Brown   // you don't have to write the namespace along with the class or
34*c4762a1bSJed Brown   // object name.  This is especially helpful with commonly used
35*c4762a1bSJed Brown   // things like std::endl or Teuchos::RCP.
36*c4762a1bSJed Brown   using std::cout;
37*c4762a1bSJed Brown   using std::endl;
38*c4762a1bSJed Brown   using Teuchos::Comm;
39*c4762a1bSJed Brown   using Teuchos::MpiComm;
40*c4762a1bSJed Brown   using Teuchos::RCP;
41*c4762a1bSJed Brown   using Teuchos::rcp;
42*c4762a1bSJed Brown 
43*c4762a1bSJed Brown   /*
44*c4762a1bSJed Brown     Every PETSc routine should begin with the PetscInitialize() routine.
45*c4762a1bSJed Brown     argc, argv - These command line arguments are taken to extract the options
46*c4762a1bSJed Brown                  supplied to PETSc and options supplied to MPI.
47*c4762a1bSJed Brown     help       - When PETSc executable is invoked with the option -help,
48*c4762a1bSJed Brown                  it prints the various options that can be applied at
49*c4762a1bSJed Brown                  runtime.  The user can use the "help" variable place
50*c4762a1bSJed Brown                  additional help messages in this printout.
51*c4762a1bSJed Brown   */
52*c4762a1bSJed Brown   ierr = PetscInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr;
53*c4762a1bSJed Brown   RCP<const Comm<int> > comm (new MpiComm<int> (PETSC_COMM_WORLD));
54*c4762a1bSJed Brown   // Get my process' rank, and the total number of processes.
55*c4762a1bSJed Brown   // Equivalent to MPI_Comm_rank resp. MPI_Comm_size.
56*c4762a1bSJed Brown   const int myRank = comm->getRank ();
57*c4762a1bSJed Brown   const int size = comm->getSize ();
58*c4762a1bSJed Brown   if (myRank == 0) {
59*c4762a1bSJed Brown     cout << "Total number of processes: " << size << endl;
60*c4762a1bSJed Brown   }
61*c4762a1bSJed Brown   // Do something with the new communicator.
62*c4762a1bSJed Brown   exampleRoutine (comm);
63*c4762a1bSJed Brown   // This tells the Trilinos test framework that the test passed.
64*c4762a1bSJed Brown   if (myRank == 0) {
65*c4762a1bSJed Brown     cout << "End Result: TEST PASSED" << endl;
66*c4762a1bSJed Brown   }
67*c4762a1bSJed Brown 
68*c4762a1bSJed Brown   ierr = PetscFinalize();
69*c4762a1bSJed Brown   return ierr;
70*c4762a1bSJed Brown }
71*c4762a1bSJed Brown 
72*c4762a1bSJed Brown 
73*c4762a1bSJed Brown /*TEST
74*c4762a1bSJed Brown 
75*c4762a1bSJed Brown    build:
76*c4762a1bSJed Brown      requires: trilinos
77*c4762a1bSJed Brown 
78*c4762a1bSJed Brown    test:
79*c4762a1bSJed Brown       nsize: 3
80*c4762a1bSJed Brown       filter: grep -v "Tpetra in Trilinos"
81*c4762a1bSJed Brown 
82*c4762a1bSJed Brown TEST*/
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