xref: /petsc/src/mat/tests/ex214.c (revision 98d129c30f3ee9fdddc40fdbc5a989b7be64f888)
1 static char help[] = "Tests MatMatSolve() and MatMatTransposeSolve() for computing inv(A) with MUMPS.\n\
2 Example: mpiexec -n <np> ./ex214 -displ \n\n";
3 
4 #include <petscmat.h>
5 
6 int main(int argc, char **args)
7 {
8   PetscMPIInt size, rank;
9 #if defined(PETSC_HAVE_MUMPS)
10   Mat         A, RHS, C, F, X, AX, spRHST;
11   PetscInt    m, n, nrhs, M, N, i, Istart, Iend, Ii, j, J, test;
12   PetscScalar v;
13   PetscReal   norm, tol = PETSC_SQRT_MACHINE_EPSILON;
14   PetscRandom rand;
15   PetscBool   displ = PETSC_FALSE;
16   char        solver[256];
17 #endif
18 
19   PetscFunctionBeginUser;
20   PetscCall(PetscInitialize(&argc, &args, (char *)0, help));
21   PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size));
22   PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));
23 
24 #if !defined(PETSC_HAVE_MUMPS)
25   if (rank == 0) PetscCall(PetscPrintf(PETSC_COMM_SELF, "This example requires MUMPS, exit...\n"));
26   PetscCall(PetscFinalize());
27   return 0;
28 #else
29 
30   PetscCall(PetscOptionsGetBool(NULL, NULL, "-displ", &displ, NULL));
31 
32   /* Create matrix A */
33   m = 4;
34   n = 4;
35   PetscCall(PetscOptionsGetInt(NULL, NULL, "-m", &m, NULL));
36   PetscCall(PetscOptionsGetInt(NULL, NULL, "-n", &n, NULL));
37 
38   PetscCall(MatCreate(PETSC_COMM_WORLD, &A));
39   PetscCall(MatSetSizes(A, PETSC_DECIDE, PETSC_DECIDE, m * n, m * n));
40   PetscCall(MatSetFromOptions(A));
41   PetscCall(MatMPIAIJSetPreallocation(A, 5, NULL, 5, NULL));
42   PetscCall(MatSeqAIJSetPreallocation(A, 5, NULL));
43 
44   PetscCall(MatGetOwnershipRange(A, &Istart, &Iend));
45   for (Ii = Istart; Ii < Iend; Ii++) {
46     v = -1.0;
47     i = Ii / n;
48     j = Ii - i * n;
49     if (i > 0) {
50       J = Ii - n;
51       PetscCall(MatSetValues(A, 1, &Ii, 1, &J, &v, ADD_VALUES));
52     }
53     if (i < m - 1) {
54       J = Ii + n;
55       PetscCall(MatSetValues(A, 1, &Ii, 1, &J, &v, ADD_VALUES));
56     }
57     if (j > 0) {
58       J = Ii - 1;
59       PetscCall(MatSetValues(A, 1, &Ii, 1, &J, &v, ADD_VALUES));
60     }
61     if (j < n - 1) {
62       J = Ii + 1;
63       PetscCall(MatSetValues(A, 1, &Ii, 1, &J, &v, ADD_VALUES));
64     }
65     v = 4.0;
66     PetscCall(MatSetValues(A, 1, &Ii, 1, &Ii, &v, ADD_VALUES));
67   }
68   PetscCall(MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY));
69   PetscCall(MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY));
70 
71   PetscCall(MatGetLocalSize(A, &m, &n));
72   PetscCall(MatGetSize(A, &M, &N));
73   PetscCheck(m == n, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "This example is not intended for rectangular matrices (%" PetscInt_FMT ", %" PetscInt_FMT ")", m, n);
74 
75   /* Create dense matrix C and X; C holds true solution with identical columns */
76   nrhs = N;
77   PetscCall(PetscOptionsGetInt(NULL, NULL, "-nrhs", &nrhs, NULL));
78   PetscCall(MatCreate(PETSC_COMM_WORLD, &C));
79   PetscCall(MatSetSizes(C, m, PETSC_DECIDE, PETSC_DECIDE, nrhs));
80   PetscCall(MatSetType(C, MATDENSE));
81   PetscCall(MatSetFromOptions(C));
82   PetscCall(MatSetUp(C));
83 
84   PetscCall(PetscRandomCreate(PETSC_COMM_WORLD, &rand));
85   PetscCall(PetscRandomSetFromOptions(rand));
86   PetscCall(MatSetRandom(C, rand));
87   PetscCall(MatDuplicate(C, MAT_DO_NOT_COPY_VALUES, &X));
88 
89   PetscCall(PetscStrncpy(solver, MATSOLVERMUMPS, sizeof(solver)));
90   if (rank == 0 && displ) PetscCall(PetscPrintf(PETSC_COMM_SELF, "Solving with %s: nrhs %" PetscInt_FMT ", size mat %" PetscInt_FMT " x %" PetscInt_FMT "\n", solver, nrhs, M, N));
91 
92   for (test = 0; test < 2; test++) {
93     if (test == 0) {
94       /* Test LU Factorization */
95       PetscCall(PetscPrintf(PETSC_COMM_WORLD, "test LU factorization\n"));
96       PetscCall(MatGetFactor(A, solver, MAT_FACTOR_LU, &F));
97       PetscCall(MatLUFactorSymbolic(F, A, NULL, NULL, NULL));
98       PetscCall(MatLUFactorNumeric(F, A, NULL));
99     } else {
100       /* Test Cholesky Factorization */
101       PetscBool flg;
102       PetscCall(MatIsSymmetric(A, 0.0, &flg));
103       PetscCheck(flg, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "A must be symmetric for Cholesky factorization");
104 
105       PetscCall(PetscPrintf(PETSC_COMM_WORLD, "test Cholesky factorization\n"));
106       PetscCall(MatGetFactor(A, solver, MAT_FACTOR_CHOLESKY, &F));
107       PetscCall(MatCholeskyFactorSymbolic(F, A, NULL, NULL));
108       PetscCall(MatCholeskyFactorNumeric(F, A, NULL));
109     }
110 
111     /* (1) Test MatMatSolve(): dense RHS = A*C, C: true solutions */
112     /* ---------------------------------------------------------- */
113     PetscCall(MatMatMult(A, C, MAT_INITIAL_MATRIX, 2.0, &RHS));
114     PetscCall(MatMatSolve(F, RHS, X));
115     /* Check the error */
116     PetscCall(MatAXPY(X, -1.0, C, SAME_NONZERO_PATTERN));
117     PetscCall(MatNorm(X, NORM_FROBENIUS, &norm));
118     if (norm > tol) PetscCall(PetscPrintf(PETSC_COMM_SELF, "(1) MatMatSolve: Norm of error %g\n", norm));
119 
120     /* Test X=RHS */
121     PetscCall(MatMatSolve(F, RHS, RHS));
122     /* Check the error */
123     PetscCall(MatAXPY(RHS, -1.0, C, SAME_NONZERO_PATTERN));
124     PetscCall(MatNorm(RHS, NORM_FROBENIUS, &norm));
125     if (norm > tol) PetscCall(PetscPrintf(PETSC_COMM_SELF, "(1.1) MatMatSolve: Norm of error %g\n", norm));
126 
127     /* (2) Test MatMatSolve() for inv(A) with dense RHS:
128      RHS = [e[0],...,e[nrhs-1]], dense X holds first nrhs columns of inv(A) */
129     /* -------------------------------------------------------------------- */
130     PetscCall(MatZeroEntries(RHS));
131     for (i = 0; i < nrhs; i++) {
132       v = 1.0;
133       PetscCall(MatSetValues(RHS, 1, &i, 1, &i, &v, INSERT_VALUES));
134     }
135     PetscCall(MatAssemblyBegin(RHS, MAT_FINAL_ASSEMBLY));
136     PetscCall(MatAssemblyEnd(RHS, MAT_FINAL_ASSEMBLY));
137 
138     PetscCall(MatMatSolve(F, RHS, X));
139     if (displ) {
140       if (rank == 0) PetscCall(PetscPrintf(PETSC_COMM_SELF, " \n(2) first %" PetscInt_FMT " columns of inv(A) with dense RHS:\n", nrhs));
141       PetscCall(MatView(X, PETSC_VIEWER_STDOUT_WORLD));
142     }
143 
144     /* Check the residual */
145     PetscCall(MatMatMult(A, X, MAT_INITIAL_MATRIX, 2.0, &AX));
146     PetscCall(MatAXPY(AX, -1.0, RHS, SAME_NONZERO_PATTERN));
147     PetscCall(MatNorm(AX, NORM_INFINITY, &norm));
148     if (norm > tol) PetscCall(PetscPrintf(PETSC_COMM_SELF, "(2) MatMatSolve: Norm of residual %g\n", norm));
149     PetscCall(MatZeroEntries(X));
150 
151     /* (3) Test MatMatTransposeSolve() for inv(A) with sparse RHS stored in the host:
152      spRHST = [e[0],...,e[nrhs-1]]^T, dense X holds first nrhs columns of inv(A) */
153     /* --------------------------------------------------------------------------- */
154     /* Create spRHST: PETSc does not support compressed column format which is required by MUMPS for sparse RHS matrix,
155      thus user must create spRHST=spRHS^T and call MatMatTransposeSolve() */
156     PetscCall(MatCreate(PETSC_COMM_WORLD, &spRHST));
157     if (rank == 0) {
158       /* MUMPS requires RHS be centralized on the host! */
159       PetscCall(MatSetSizes(spRHST, nrhs, M, PETSC_DECIDE, PETSC_DECIDE));
160     } else {
161       PetscCall(MatSetSizes(spRHST, 0, 0, PETSC_DECIDE, PETSC_DECIDE));
162     }
163     PetscCall(MatSetType(spRHST, MATAIJ));
164     PetscCall(MatSetFromOptions(spRHST));
165     PetscCall(MatSetUp(spRHST));
166     if (rank == 0) {
167       v = 1.0;
168       for (i = 0; i < nrhs; i++) PetscCall(MatSetValues(spRHST, 1, &i, 1, &i, &v, INSERT_VALUES));
169     }
170     PetscCall(MatAssemblyBegin(spRHST, MAT_FINAL_ASSEMBLY));
171     PetscCall(MatAssemblyEnd(spRHST, MAT_FINAL_ASSEMBLY));
172 
173     PetscCall(MatMatTransposeSolve(F, spRHST, X));
174 
175     if (displ) {
176       if (rank == 0) PetscCall(PetscPrintf(PETSC_COMM_SELF, " \n(3) first %" PetscInt_FMT " columns of inv(A) with sparse RHS:\n", nrhs));
177       PetscCall(MatView(X, PETSC_VIEWER_STDOUT_WORLD));
178     }
179 
180     /* Check the residual: R = A*X - RHS */
181     PetscCall(MatMatMult(A, X, MAT_REUSE_MATRIX, 2.0, &AX));
182 
183     PetscCall(MatAXPY(AX, -1.0, RHS, SAME_NONZERO_PATTERN));
184     PetscCall(MatNorm(AX, NORM_INFINITY, &norm));
185     if (norm > tol) PetscCall(PetscPrintf(PETSC_COMM_SELF, "(3) MatMatSolve: Norm of residual %g\n", norm));
186 
187     /* (4) Test MatMatSolve() for inv(A) with selected entries:
188      input: spRHS gives selected indices; output: spRHS holds selected entries of inv(A) */
189     /* --------------------------------------------------------------------------------- */
190     if (nrhs == N) { /* mumps requires nrhs = n */
191       /* Create spRHS on proc[0] */
192       Mat spRHS = NULL;
193 
194       /* Create spRHS = spRHST^T. Two matrices share internal matrix data structure */
195       PetscCall(MatCreateTranspose(spRHST, &spRHS));
196       PetscCall(MatMumpsGetInverse(F, spRHS));
197       PetscCall(MatDestroy(&spRHS));
198 
199       PetscCall(MatMumpsGetInverseTranspose(F, spRHST));
200       if (displ) {
201         PetscCall(PetscPrintf(PETSC_COMM_WORLD, "\nSelected entries of inv(A^T):\n"));
202         PetscCall(MatView(spRHST, PETSC_VIEWER_STDOUT_WORLD));
203       }
204       PetscCall(MatDestroy(&spRHS));
205     }
206     PetscCall(MatDestroy(&AX));
207     PetscCall(MatDestroy(&F));
208     PetscCall(MatDestroy(&RHS));
209     PetscCall(MatDestroy(&spRHST));
210   }
211 
212   /* Free data structures */
213   PetscCall(MatDestroy(&A));
214   PetscCall(MatDestroy(&C));
215   PetscCall(MatDestroy(&X));
216   PetscCall(PetscRandomDestroy(&rand));
217   PetscCall(PetscFinalize());
218   return 0;
219 #endif
220 }
221 
222 /*TEST
223 
224    test:
225      requires: mumps double !complex
226 
227    test:
228      suffix: 2
229      requires: mumps double !complex
230      nsize: 2
231 
232 TEST*/
233