xref: /petsc/src/mat/tests/ex130.c (revision daa037dfd3c3bec8dc8659548d2b20b07c1dc6de)
1 
2 static char help[] = "Tests external direct solvers. Simplified from ex125.c\n\
3 Example: mpiexec -n <np> ./ex130 -f <matrix binary file> -mat_solver_type 1 -mat_superlu_equil \n\n";
4 
5 #include <petscmat.h>
6 
7 int main(int argc,char **args)
8 {
9   Mat            A,F;
10   Vec            u,x,b;
11   PetscMPIInt    rank,size;
12   PetscInt       m,n,nfact,ipack=0;
13   PetscReal      norm,tol=1.e-12,Anorm;
14   IS             perm,iperm;
15   MatFactorInfo  info;
16   PetscBool      flg,testMatSolve=PETSC_TRUE;
17   PetscViewer    fd;              /* viewer */
18   char           file[PETSC_MAX_PATH_LEN]; /* input file name */
19 
20   PetscCall(PetscInitialize(&argc,&args,(char*)0,help));
21   PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));
22   PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size));
23 
24   /* Determine file from which we read the matrix A */
25   PetscCall(PetscOptionsGetString(NULL,NULL,"-f",file,sizeof(file),&flg));
26   PetscCheck(flg,PETSC_COMM_WORLD,PETSC_ERR_USER,"Must indicate binary file with the -f option");
27 
28   /* Load matrix A */
29   PetscCall(PetscViewerBinaryOpen(PETSC_COMM_WORLD,file,FILE_MODE_READ,&fd));
30   PetscCall(MatCreate(PETSC_COMM_WORLD,&A));
31   PetscCall(MatLoad(A,fd));
32   PetscCall(VecCreate(PETSC_COMM_WORLD,&b));
33   PetscCall(VecLoad(b,fd));
34   PetscCall(PetscViewerDestroy(&fd));
35   PetscCall(MatGetLocalSize(A,&m,&n));
36   PetscCheck(m == n,PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ, "This example is not intended for rectangular matrices (%d, %d)", m, n);
37   PetscCall(MatNorm(A,NORM_INFINITY,&Anorm));
38 
39   /* Create vectors */
40   PetscCall(VecDuplicate(b,&x));
41   PetscCall(VecDuplicate(x,&u)); /* save the true solution */
42 
43   /* Test LU Factorization */
44   PetscCall(MatGetOrdering(A,MATORDERINGNATURAL,&perm,&iperm));
45 
46   PetscCall(PetscOptionsGetInt(NULL,NULL,"-mat_solver_type",&ipack,NULL));
47   switch (ipack) {
48   case 1:
49 #if defined(PETSC_HAVE_SUPERLU)
50     if (rank == 0) printf(" SUPERLU LU:\n");
51     PetscCall(MatGetFactor(A,MATSOLVERSUPERLU,MAT_FACTOR_LU,&F));
52     break;
53 #endif
54   case 2:
55 #if defined(PETSC_HAVE_MUMPS)
56     if (rank == 0) printf(" MUMPS LU:\n");
57     PetscCall(MatGetFactor(A,MATSOLVERMUMPS,MAT_FACTOR_LU,&F));
58     {
59       /* test mumps options */
60       PetscInt icntl_7 = 5;
61       PetscCall(MatMumpsSetIcntl(F,7,icntl_7));
62     }
63     break;
64 #endif
65   default:
66     if (rank == 0) printf(" PETSC LU:\n");
67     PetscCall(MatGetFactor(A,MATSOLVERPETSC,MAT_FACTOR_LU,&F));
68   }
69 
70   info.fill = 5.0;
71   PetscCall(MatLUFactorSymbolic(F,A,perm,iperm,&info));
72 
73   for (nfact = 0; nfact < 1; nfact++) {
74     if (rank == 0) printf(" %d-the LU numfactorization \n",nfact);
75     PetscCall(MatLUFactorNumeric(F,A,&info));
76 
77     /* Test MatSolve() */
78     if (testMatSolve) {
79       PetscCall(MatSolve(F,b,x));
80 
81       /* Check the residual */
82       PetscCall(MatMult(A,x,u));
83       PetscCall(VecAXPY(u,-1.0,b));
84       PetscCall(VecNorm(u,NORM_INFINITY,&norm));
85       if (norm > tol) {
86         if (rank == 0) {
87           PetscCall(PetscPrintf(PETSC_COMM_SELF,"MatSolve: rel residual %g/%g = %g, LU numfact %d\n",norm,Anorm,norm/Anorm,nfact));
88         }
89       }
90     }
91   }
92 
93   /* Free data structures */
94   PetscCall(MatDestroy(&A));
95   PetscCall(MatDestroy(&F));
96   PetscCall(ISDestroy(&perm));
97   PetscCall(ISDestroy(&iperm));
98   PetscCall(VecDestroy(&x));
99   PetscCall(VecDestroy(&b));
100   PetscCall(VecDestroy(&u));
101   PetscCall(PetscFinalize());
102   return 0;
103 }
104