Actual source code: ex185.c
1: static char help[] = "Tests MatCreateConstantDiagonal().\n"
2: "\n";
4: #include <petscmat.h>
6: int main(int argc, char **args)
7: {
8: Vec X, Y;
9: Mat A, B, Af;
10: PetscBool flg;
11: PetscReal xnorm, ynorm, anorm;
13: PetscFunctionBeginUser;
14: PetscCall(PetscInitialize(&argc, &args, (char *)0, help));
16: PetscCall(MatCreateConstantDiagonal(PETSC_COMM_WORLD, PETSC_DETERMINE, PETSC_DETERMINE, 20, 20, 3.0, &A));
17: PetscCall(MatCreateVecs(A, &X, &Y));
18: PetscCall(MatView(A, PETSC_VIEWER_STDOUT_WORLD));
20: PetscCall(VecSetRandom(X, NULL));
21: PetscCall(VecNorm(X, NORM_2, &xnorm));
22: PetscCall(MatMult(A, X, Y));
23: PetscCall(VecNorm(Y, NORM_2, &ynorm));
24: PetscCheck(PetscAbsReal(ynorm - 3 * xnorm) <= PETSC_SMALL, PETSC_COMM_WORLD, PETSC_ERR_PLIB, "Expected norm %g actual norm %g", (double)(3 * xnorm), (double)ynorm);
25: PetscCall(MatShift(A, 5.0));
26: PetscCall(MatScale(A, .5));
27: PetscCall(MatView(A, PETSC_VIEWER_STDOUT_WORLD));
28: PetscCall(MatNorm(A, NORM_FROBENIUS, &anorm));
29: PetscCheck(PetscAbsReal(anorm - 4.0) <= PETSC_SMALL, PETSC_COMM_WORLD, PETSC_ERR_PLIB, "Expected norm 4.0 actual norm %g", (double)anorm);
31: /* Convert to AIJ (exercises MatGetRow/MatRestoreRow) */
32: PetscCall(MatConvert(A, MATAIJ, MAT_INITIAL_MATRIX, &B));
33: PetscCall(MatMultEqual(A, B, 10, &flg));
34: if (!flg) PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Error MatMult\n"));
35: PetscCall(MatMultAddEqual(A, B, 10, &flg));
36: if (!flg) PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Error MatMultAdd\n"));
37: PetscCall(MatMultTransposeEqual(A, B, 10, &flg));
38: if (!flg) PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Error MatMultTranspose\n"));
39: PetscCall(MatMultTransposeAddEqual(A, B, 10, &flg));
40: if (!flg) PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Error MatMultTransposeAdd\n"));
42: PetscCall(MatGetDiagonal(A, Y));
43: PetscCall(MatGetFactor(A, MATSOLVERPETSC, MAT_FACTOR_LU, &Af));
44: PetscCall(MatLUFactorSymbolic(Af, A, NULL, NULL, NULL));
45: PetscCall(MatLUFactorNumeric(Af, A, NULL));
46: PetscCall(MatSolve(Af, X, Y));
47: PetscCall(VecNorm(Y, NORM_2, &ynorm));
48: PetscCheck(PetscAbsReal(ynorm - xnorm / 4) <= PETSC_SMALL, PETSC_COMM_WORLD, PETSC_ERR_PLIB, "Expected norm %g actual norm %g", (double)(.25 * xnorm), (double)ynorm);
50: PetscCall(MatDestroy(&A));
51: PetscCall(MatDestroy(&B));
52: PetscCall(MatDestroy(&Af));
53: PetscCall(VecDestroy(&X));
54: PetscCall(VecDestroy(&Y));
56: PetscCall(PetscFinalize());
57: return 0;
58: }
60: /*TEST
62: test:
63: nsize: 2
65: TEST*/