1c4762a1bSJed Brown 2c4762a1bSJed Brown static char help[] = "Tests relaxation for dense matrices.\n\n"; 3c4762a1bSJed Brown 4c4762a1bSJed Brown #include <petscmat.h> 5c4762a1bSJed Brown 6*d71ae5a4SJacob Faibussowitsch int main(int argc, char **args) 7*d71ae5a4SJacob Faibussowitsch { 8c4762a1bSJed Brown Mat C; 9c4762a1bSJed Brown Vec u, x, b, e; 10c4762a1bSJed Brown PetscInt i, n = 10, midx[3]; 11c4762a1bSJed Brown PetscScalar v[3]; 12c4762a1bSJed Brown PetscReal omega = 1.0, norm; 13c4762a1bSJed Brown 14327415f7SBarry Smith PetscFunctionBeginUser; 159566063dSJacob Faibussowitsch PetscCall(PetscInitialize(&argc, &args, (char *)0, help)); 169566063dSJacob Faibussowitsch PetscCall(PetscOptionsGetReal(NULL, NULL, "-omega", &omega, NULL)); 179566063dSJacob Faibussowitsch PetscCall(PetscOptionsGetInt(NULL, NULL, "-n", &n, NULL)); 18c4762a1bSJed Brown 199566063dSJacob Faibussowitsch PetscCall(MatCreate(PETSC_COMM_SELF, &C)); 209566063dSJacob Faibussowitsch PetscCall(MatSetSizes(C, n, n, n, n)); 219566063dSJacob Faibussowitsch PetscCall(MatSetType(C, MATSEQDENSE)); 229566063dSJacob Faibussowitsch PetscCall(MatSetUp(C)); 239566063dSJacob Faibussowitsch PetscCall(VecCreateSeq(PETSC_COMM_SELF, n, &b)); 249566063dSJacob Faibussowitsch PetscCall(VecCreateSeq(PETSC_COMM_SELF, n, &x)); 259566063dSJacob Faibussowitsch PetscCall(VecCreateSeq(PETSC_COMM_SELF, n, &u)); 269566063dSJacob Faibussowitsch PetscCall(VecCreateSeq(PETSC_COMM_SELF, n, &e)); 279566063dSJacob Faibussowitsch PetscCall(VecSet(u, 1.0)); 289566063dSJacob Faibussowitsch PetscCall(VecSet(x, 0.0)); 29c4762a1bSJed Brown 309371c9d4SSatish Balay v[0] = -1.; 319371c9d4SSatish Balay v[1] = 2.; 329371c9d4SSatish Balay v[2] = -1.; 33c4762a1bSJed Brown for (i = 1; i < n - 1; i++) { 349371c9d4SSatish Balay midx[0] = i - 1; 359371c9d4SSatish Balay midx[1] = i; 369371c9d4SSatish Balay midx[2] = i + 1; 379566063dSJacob Faibussowitsch PetscCall(MatSetValues(C, 1, &i, 3, midx, v, INSERT_VALUES)); 38c4762a1bSJed Brown } 399371c9d4SSatish Balay i = 0; 409371c9d4SSatish Balay midx[0] = 0; 419371c9d4SSatish Balay midx[1] = 1; 429371c9d4SSatish Balay v[0] = 2.0; 439371c9d4SSatish Balay v[1] = -1.; 449566063dSJacob Faibussowitsch PetscCall(MatSetValues(C, 1, &i, 2, midx, v, INSERT_VALUES)); 459371c9d4SSatish Balay i = n - 1; 469371c9d4SSatish Balay midx[0] = n - 2; 479371c9d4SSatish Balay midx[1] = n - 1; 489371c9d4SSatish Balay v[0] = -1.0; 499371c9d4SSatish Balay v[1] = 2.; 509566063dSJacob Faibussowitsch PetscCall(MatSetValues(C, 1, &i, 2, midx, v, INSERT_VALUES)); 51c4762a1bSJed Brown 529566063dSJacob Faibussowitsch PetscCall(MatAssemblyBegin(C, MAT_FINAL_ASSEMBLY)); 539566063dSJacob Faibussowitsch PetscCall(MatAssemblyEnd(C, MAT_FINAL_ASSEMBLY)); 54c4762a1bSJed Brown 559566063dSJacob Faibussowitsch PetscCall(MatMult(C, u, b)); 56c4762a1bSJed Brown 57c4762a1bSJed Brown for (i = 0; i < n; i++) { 589566063dSJacob Faibussowitsch PetscCall(MatSOR(C, b, omega, SOR_FORWARD_SWEEP, 0.0, 1, 1, x)); 599566063dSJacob Faibussowitsch PetscCall(VecWAXPY(e, -1.0, x, u)); 609566063dSJacob Faibussowitsch PetscCall(VecNorm(e, NORM_2, &norm)); 619566063dSJacob Faibussowitsch PetscCall(PetscPrintf(PETSC_COMM_SELF, "2-norm of error %g\n", (double)norm)); 62c4762a1bSJed Brown } 639566063dSJacob Faibussowitsch PetscCall(MatDestroy(&C)); 649566063dSJacob Faibussowitsch PetscCall(VecDestroy(&x)); 659566063dSJacob Faibussowitsch PetscCall(VecDestroy(&b)); 669566063dSJacob Faibussowitsch PetscCall(VecDestroy(&u)); 679566063dSJacob Faibussowitsch PetscCall(VecDestroy(&e)); 689566063dSJacob Faibussowitsch PetscCall(PetscFinalize()); 69b122ec5aSJacob Faibussowitsch return 0; 70c4762a1bSJed Brown } 71c4762a1bSJed Brown 72c4762a1bSJed Brown /*TEST 73c4762a1bSJed Brown 74c4762a1bSJed Brown test: 75c4762a1bSJed Brown 76c4762a1bSJed Brown TEST*/ 77