xref: /petsc/src/mat/tests/ex168.c (revision b122ec5aa1bd4469eb4e0673542fb7de3f411254)
1c4762a1bSJed Brown 
2c4762a1bSJed Brown static char help[] = "Tests external Clique direct solvers. Simplified from ex130.c\n\
3c4762a1bSJed Brown Example: mpiexec -n <np> ./ex168 -f <matrix binary file> \n\n";
4c4762a1bSJed Brown 
5c4762a1bSJed Brown #include <petscmat.h>
6c4762a1bSJed Brown 
7c4762a1bSJed Brown int main(int argc,char **args)
8c4762a1bSJed Brown {
9c4762a1bSJed Brown   Mat            A,F;
10c4762a1bSJed Brown   Vec            u,x,b;
11c4762a1bSJed Brown   PetscMPIInt    rank,size;
12c4762a1bSJed Brown   PetscInt       m,n,nfact;
13c4762a1bSJed Brown   PetscReal      norm,tol=1.e-12,Anorm;
14c4762a1bSJed Brown   IS             perm,iperm;
15c4762a1bSJed Brown   MatFactorInfo  info;
16c4762a1bSJed Brown   PetscBool      flg,testMatSolve=PETSC_TRUE;
17c4762a1bSJed Brown   PetscViewer    fd;              /* viewer */
18c4762a1bSJed Brown   char           file[PETSC_MAX_PATH_LEN]; /* input file name */
19c4762a1bSJed Brown 
20*b122ec5aSJacob Faibussowitsch   CHKERRQ(PetscInitialize(&argc,&args,(char*)0,help));
215f80ce2aSJacob Faibussowitsch   CHKERRMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));
225f80ce2aSJacob Faibussowitsch   CHKERRMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size));
23c4762a1bSJed Brown 
24c4762a1bSJed Brown   /* Determine file from which we read the matrix A */
255f80ce2aSJacob Faibussowitsch   CHKERRQ(PetscOptionsGetString(NULL,NULL,"-f",file,sizeof(file),&flg));
2628b400f6SJacob Faibussowitsch   PetscCheck(flg,PETSC_COMM_WORLD,PETSC_ERR_USER,"Must indicate binary file with the -f option");
27c4762a1bSJed Brown 
28c4762a1bSJed Brown   /* Load matrix A */
295f80ce2aSJacob Faibussowitsch   CHKERRQ(PetscViewerBinaryOpen(PETSC_COMM_WORLD,file,FILE_MODE_READ,&fd));
305f80ce2aSJacob Faibussowitsch   CHKERRQ(MatCreate(PETSC_COMM_WORLD,&A));
315f80ce2aSJacob Faibussowitsch   CHKERRQ(MatLoad(A,fd));
325f80ce2aSJacob Faibussowitsch   CHKERRQ(VecCreate(PETSC_COMM_WORLD,&b));
335f80ce2aSJacob Faibussowitsch   CHKERRQ(VecLoad(b,fd));
345f80ce2aSJacob Faibussowitsch   CHKERRQ(PetscViewerDestroy(&fd));
355f80ce2aSJacob Faibussowitsch   CHKERRQ(MatGetLocalSize(A,&m,&n));
362c71b3e2SJacob Faibussowitsch   PetscCheckFalse(m != n,PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ, "This example is not intended for rectangular matrices (%d, %d)", m, n);
375f80ce2aSJacob Faibussowitsch   CHKERRQ(MatNorm(A,NORM_INFINITY,&Anorm));
38c4762a1bSJed Brown 
39c4762a1bSJed Brown   /* Create vectors */
405f80ce2aSJacob Faibussowitsch   CHKERRQ(VecDuplicate(b,&x));
415f80ce2aSJacob Faibussowitsch   CHKERRQ(VecDuplicate(x,&u)); /* save the true solution */
42c4762a1bSJed Brown 
43c4762a1bSJed Brown   /* Test Cholesky Factorization */
445f80ce2aSJacob Faibussowitsch   CHKERRQ(MatGetOrdering(A,MATORDERINGNATURAL,&perm,&iperm));
45c4762a1bSJed Brown 
46dd400576SPatrick Sanan   if (rank == 0) printf(" Clique Cholesky:\n");
475f80ce2aSJacob Faibussowitsch   CHKERRQ(MatGetFactor(A,MATSOLVERCLIQUE,MAT_FACTOR_CHOLESKY,&F));
48c4762a1bSJed Brown 
49c4762a1bSJed Brown   info.fill = 5.0;
505f80ce2aSJacob Faibussowitsch   CHKERRQ(MatCholeskyFactorSymbolic(F,A,perm,&info));
51c4762a1bSJed Brown 
52c4762a1bSJed Brown   for (nfact = 0; nfact < 1; nfact++) {
53dd400576SPatrick Sanan     if (rank == 0) printf(" %d-the Cholesky numfactorization \n",nfact);
545f80ce2aSJacob Faibussowitsch     CHKERRQ(MatCholeskyFactorNumeric(F,A,&info));
55c4762a1bSJed Brown 
56c4762a1bSJed Brown     /* Test MatSolve() */
57c4762a1bSJed Brown     if (testMatSolve && nfact == 2) {
585f80ce2aSJacob Faibussowitsch       CHKERRQ(MatSolve(F,b,x));
59c4762a1bSJed Brown 
60c4762a1bSJed Brown       /* Check the residual */
615f80ce2aSJacob Faibussowitsch       CHKERRQ(MatMult(A,x,u));
625f80ce2aSJacob Faibussowitsch       CHKERRQ(VecAXPY(u,-1.0,b));
635f80ce2aSJacob Faibussowitsch       CHKERRQ(VecNorm(u,NORM_INFINITY,&norm));
64c4762a1bSJed Brown       /* if (norm > tol) { */
65dd400576SPatrick Sanan       if (rank == 0) {
665f80ce2aSJacob Faibussowitsch         CHKERRQ(PetscPrintf(PETSC_COMM_SELF,"MatSolve: rel residual %g/%g = %g, LU numfact %d\n",norm,Anorm,norm/Anorm,nfact));
67c4762a1bSJed Brown       }
68c4762a1bSJed Brown       /*} */
69c4762a1bSJed Brown     }
70c4762a1bSJed Brown   }
71c4762a1bSJed Brown 
72c4762a1bSJed Brown   /* Free data structures */
735f80ce2aSJacob Faibussowitsch   CHKERRQ(MatDestroy(&A));
745f80ce2aSJacob Faibussowitsch   CHKERRQ(MatDestroy(&F));
755f80ce2aSJacob Faibussowitsch   CHKERRQ(ISDestroy(&perm));
765f80ce2aSJacob Faibussowitsch   CHKERRQ(ISDestroy(&iperm));
775f80ce2aSJacob Faibussowitsch   CHKERRQ(VecDestroy(&x));
785f80ce2aSJacob Faibussowitsch   CHKERRQ(VecDestroy(&b));
795f80ce2aSJacob Faibussowitsch   CHKERRQ(VecDestroy(&u));
80*b122ec5aSJacob Faibussowitsch   CHKERRQ(PetscFinalize());
81*b122ec5aSJacob Faibussowitsch   return 0;
82c4762a1bSJed Brown }
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