xref: /petsc/src/mat/tests/ex209.c (revision c4762a1b19cd2af06abeed90e8f9d34fb975dd94)
1 static char help[] = "Test MatTransposeMatMult() \n\n";
2 
3 /* Example:
4   mpiexec -n 8 ./ex209 -f <inputfile> (e.g., inputfile=ceres_solver_iteration_001_A.petsc)
5 */
6 
7 #include <petscmat.h>
8 
9 int main(int argc,char **args)
10 {
11   Mat            A,C,AtA,B;
12   PetscViewer    fd;
13   char           file[PETSC_MAX_PATH_LEN];
14   PetscErrorCode ierr;
15   PetscReal      fill = 4.0;
16   PetscMPIInt    rank,size;
17   PetscBool      equal;
18   PetscInt       i,m,n,rstart,rend;
19   PetscScalar    one=1.0;
20 
21   ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr;
22   ierr = MPI_Comm_rank(PETSC_COMM_WORLD,&rank);CHKERRQ(ierr);
23   ierr = MPI_Comm_size(PETSC_COMM_WORLD,&size);CHKERRQ(ierr);
24   ierr = PetscOptionsGetString(NULL,NULL,"-f",file,PETSC_MAX_PATH_LEN,NULL);CHKERRQ(ierr);
25 
26   /* Load matrix A */
27   ierr = PetscViewerBinaryOpen(PETSC_COMM_WORLD,file,FILE_MODE_READ,&fd);CHKERRQ(ierr);
28   ierr = MatCreate(PETSC_COMM_WORLD,&A);CHKERRQ(ierr);
29   ierr = MatSetType(A,MATAIJ);CHKERRQ(ierr);
30   ierr = MatLoad(A,fd);CHKERRQ(ierr);
31   ierr = PetscViewerDestroy(&fd);CHKERRQ(ierr);
32 
33   /* Create identity matrix B */
34   ierr = MatGetLocalSize(A,&m,&n);CHKERRQ(ierr);
35   ierr = MatCreate(PETSC_COMM_WORLD,&B);CHKERRQ(ierr);
36   ierr = MatSetSizes(B,m,m,PETSC_DECIDE,PETSC_DECIDE);CHKERRQ(ierr);
37   ierr = MatSetType(B,MATAIJ);CHKERRQ(ierr);
38   ierr = MatSetFromOptions(B);CHKERRQ(ierr);
39   ierr = MatSetUp(B);CHKERRQ(ierr);
40 
41   ierr = MatGetOwnershipRange(B,&rstart,&rend);CHKERRQ(ierr);
42   for (i=rstart; i<rend; i++) {
43     ierr = MatSetValues(B,1,&i,1,&i,&one,INSERT_VALUES);CHKERRQ(ierr);
44   }
45   ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
46   ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
47 
48   /* Compute AtA = A^T*B*A, B = identity matrix */
49   ierr = MatPtAP(B,A,MAT_INITIAL_MATRIX,fill,&AtA);CHKERRQ(ierr);
50   ierr = MatPtAP(B,A,MAT_REUSE_MATRIX,fill,&AtA);CHKERRQ(ierr);
51   if (!rank) printf("C = A^T*B*A is done...\n");
52   ierr = MatDestroy(&B);CHKERRQ(ierr);
53 
54   /* Compute C = A^T*A */
55   ierr = MatTransposeMatMult(A,A,MAT_INITIAL_MATRIX,fill,&C);CHKERRQ(ierr);
56   if (!rank) printf("C = A^T*A is done...\n");
57   ierr = MatTransposeMatMult(A,A,MAT_REUSE_MATRIX,fill,&C);CHKERRQ(ierr);
58   if (!rank) printf("REUSE C = A^T*A is done...\n");
59 
60   /* Compare C and AtA */
61   ierr = MatMultEqual(C,AtA,20,&equal);CHKERRQ(ierr);
62   if (!equal) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"A^T*A != At*A");
63   ierr = MatDestroy(&AtA);CHKERRQ(ierr);
64 
65   ierr = MatDestroy(&C);CHKERRQ(ierr);
66   ierr = MatDestroy(&A);CHKERRQ(ierr);
67   ierr = PetscFinalize();
68   return ierr;
69 }
70 
71 
72 /*TEST
73 
74    test:
75       requires: datafilespath !complex double !define(PETSC_USE_64BIT_INDICES)
76       args: -f ${DATAFILESPATH}/matrices/arco1
77 
78    test:
79       suffix: 2
80       nsize: 4
81       requires: datafilespath !complex double !define(PETSC_USE_64BIT_INDICES)
82       args: -f ${DATAFILESPATH}/matrices/arco1 -matptap_via nonscalable
83 
84 TEST*/
85