xref: /petsc/src/mat/tests/ex130.c (revision 030f984af8d8bb4c203755d35bded3c05b3d83ce)
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   PetscErrorCode ierr;
12   PetscMPIInt    rank,size;
13   PetscInt       m,n,nfact,ipack=0;
14   PetscReal      norm,tol=1.e-12,Anorm;
15   IS             perm,iperm;
16   MatFactorInfo  info;
17   PetscBool      flg,testMatSolve=PETSC_TRUE;
18   PetscViewer    fd;              /* viewer */
19   char           file[PETSC_MAX_PATH_LEN]; /* input file name */
20 
21   ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr;
22   ierr = MPI_Comm_rank(PETSC_COMM_WORLD, &rank);CHKERRMPI(ierr);
23   ierr = MPI_Comm_size(PETSC_COMM_WORLD, &size);CHKERRMPI(ierr);
24 
25   /* Determine file from which we read the matrix A */
26   ierr = PetscOptionsGetString(NULL,NULL,"-f",file,sizeof(file),&flg);CHKERRQ(ierr);
27   if (!flg) SETERRQ(PETSC_COMM_WORLD,PETSC_ERR_USER,"Must indicate binary file with the -f option");
28 
29   /* Load matrix A */
30   ierr = PetscViewerBinaryOpen(PETSC_COMM_WORLD,file,FILE_MODE_READ,&fd);CHKERRQ(ierr);
31   ierr = MatCreate(PETSC_COMM_WORLD,&A);CHKERRQ(ierr);
32   ierr = MatLoad(A,fd);CHKERRQ(ierr);
33   ierr = VecCreate(PETSC_COMM_WORLD,&b);CHKERRQ(ierr);
34   ierr = VecLoad(b,fd);CHKERRQ(ierr);
35   ierr = PetscViewerDestroy(&fd);CHKERRQ(ierr);
36   ierr = MatGetLocalSize(A,&m,&n);CHKERRQ(ierr);
37   if (m != n) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ, "This example is not intended for rectangular matrices (%d, %d)", m, n);
38   ierr = MatNorm(A,NORM_INFINITY,&Anorm);CHKERRQ(ierr);
39 
40   /* Create vectors */
41   ierr = VecDuplicate(b,&x);CHKERRQ(ierr);
42   ierr = VecDuplicate(x,&u);CHKERRQ(ierr); /* save the true solution */
43 
44   /* Test LU Factorization */
45   ierr = MatGetOrdering(A,MATORDERINGNATURAL,&perm,&iperm);CHKERRQ(ierr);
46 
47   ierr = PetscOptionsGetInt(NULL,NULL,"-mat_solver_type",&ipack,NULL);CHKERRQ(ierr);
48   switch (ipack) {
49   case 1:
50 #if defined(PETSC_HAVE_SUPERLU)
51     if (!rank) printf(" SUPERLU LU:\n");
52     ierr = MatGetFactor(A,MATSOLVERSUPERLU,MAT_FACTOR_LU,&F);CHKERRQ(ierr);
53     break;
54 #endif
55   case 2:
56 #if defined(PETSC_HAVE_MUMPS)
57     if (!rank) printf(" MUMPS LU:\n");
58     ierr = MatGetFactor(A,MATSOLVERMUMPS,MAT_FACTOR_LU,&F);CHKERRQ(ierr);
59     {
60       /* test mumps options */
61       PetscInt icntl_7 = 5;
62       ierr = MatMumpsSetIcntl(F,7,icntl_7);CHKERRQ(ierr);
63     }
64     break;
65 #endif
66   default:
67     if (!rank) printf(" PETSC LU:\n");
68     ierr = MatGetFactor(A,MATSOLVERPETSC,MAT_FACTOR_LU,&F);CHKERRQ(ierr);
69   }
70 
71   info.fill = 5.0;
72   ierr      = MatLUFactorSymbolic(F,A,perm,iperm,&info);CHKERRQ(ierr);
73 
74   for (nfact = 0; nfact < 1; nfact++) {
75     if (!rank) printf(" %d-the LU numfactorization \n",nfact);
76     ierr = MatLUFactorNumeric(F,A,&info);CHKERRQ(ierr);
77 
78     /* Test MatSolve() */
79     if (testMatSolve) {
80       ierr = MatSolve(F,b,x);CHKERRQ(ierr);
81 
82       /* Check the residual */
83       ierr = MatMult(A,x,u);CHKERRQ(ierr);
84       ierr = VecAXPY(u,-1.0,b);CHKERRQ(ierr);
85       ierr = VecNorm(u,NORM_INFINITY,&norm);CHKERRQ(ierr);
86       if (norm > tol) {
87         if (!rank) {
88           ierr = PetscPrintf(PETSC_COMM_SELF,"MatSolve: rel residual %g/%g = %g, LU numfact %d\n",norm,Anorm,norm/Anorm,nfact);CHKERRQ(ierr);
89         }
90       }
91     }
92   }
93 
94   /* Free data structures */
95   ierr = MatDestroy(&A);CHKERRQ(ierr);
96   ierr = MatDestroy(&F);CHKERRQ(ierr);
97   ierr = ISDestroy(&perm);CHKERRQ(ierr);
98   ierr = ISDestroy(&iperm);CHKERRQ(ierr);
99   ierr = VecDestroy(&x);CHKERRQ(ierr);
100   ierr = VecDestroy(&b);CHKERRQ(ierr);
101   ierr = VecDestroy(&u);CHKERRQ(ierr);
102   ierr = PetscFinalize();
103   return ierr;
104 }
105