xref: /petsc/src/mat/tests/ex18.c (revision 40badf4fbc550ac1f60bd080eaff6de6d55b946d)
1 static char help[] = "Tests the use of MatZeroRowsColumns() for parallel matrices.\n\
2 Contributed-by: Stephan Kramer <s.kramer@imperial.ac.uk>\n\n";
3 
4 #include <petscmat.h>
5 
6 int main(int argc,char **args)
7 {
8   Mat            A;
9   Vec            x, rhs, y;
10   PetscInt       i,j,k,b,m = 3,n,nlocal=2,bs=1,Ii,J;
11   PetscInt       *boundary_nodes, nboundary_nodes, *boundary_indices;
12   PetscMPIInt    rank,size;
13   PetscErrorCode ierr;
14   PetscScalar    v,v0,v1,v2,a0=0.1,a,rhsval, *boundary_values,diag = 1.0;
15   PetscReal      norm;
16   char           convname[64];
17   PetscBool      upwind = PETSC_FALSE, nonlocalBC = PETSC_FALSE, zerorhs = PETSC_TRUE, convert = PETSC_FALSE;
18 
19   ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr;
20   CHKERRMPI(MPI_Comm_rank(PETSC_COMM_WORLD,&rank));
21   CHKERRMPI(MPI_Comm_size(PETSC_COMM_WORLD,&size));
22   n = nlocal*size;
23 
24   CHKERRQ(PetscOptionsGetInt(NULL,NULL, "-bs", &bs, NULL));
25   CHKERRQ(PetscOptionsGetBool(NULL,NULL, "-nonlocal_bc", &nonlocalBC, NULL));
26   CHKERRQ(PetscOptionsGetScalar(NULL,NULL, "-diag", &diag, NULL));
27   CHKERRQ(PetscOptionsGetString(NULL,NULL,"-convname",convname,sizeof(convname),&convert));
28   CHKERRQ(PetscOptionsGetBool(NULL,NULL, "-zerorhs", &zerorhs, NULL));
29 
30   CHKERRQ(MatCreate(PETSC_COMM_WORLD,&A));
31   CHKERRQ(MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,m*n*bs,m*n*bs));
32   CHKERRQ(MatSetFromOptions(A));
33   CHKERRQ(MatSetUp(A));
34 
35   CHKERRQ(MatCreateVecs(A, NULL, &rhs));
36   CHKERRQ(VecSetFromOptions(rhs));
37   CHKERRQ(VecSetUp(rhs));
38 
39   rhsval = 0.0;
40   for (i=0; i<m; i++) {
41     for (j=nlocal*rank; j<nlocal*(rank+1); j++) {
42       a = a0;
43       for (b=0; b<bs; b++) {
44         /* let's start with a 5-point stencil diffusion term */
45         v = -1.0;  Ii = (j + n*i)*bs + b;
46         if (i>0)   {J = Ii - n*bs; CHKERRQ(MatSetValues(A,1,&Ii,1,&J,&v,ADD_VALUES));}
47         if (i<m-1) {J = Ii + n*bs; CHKERRQ(MatSetValues(A,1,&Ii,1,&J,&v,ADD_VALUES));}
48         if (j>0)   {J = Ii - 1*bs; CHKERRQ(MatSetValues(A,1,&Ii,1,&J,&v,ADD_VALUES));}
49         if (j<n-1) {J = Ii + 1*bs; CHKERRQ(MatSetValues(A,1,&Ii,1,&J,&v,ADD_VALUES));}
50         v = 4.0; CHKERRQ(MatSetValues(A,1,&Ii,1,&Ii,&v,ADD_VALUES));
51         if (upwind) {
52           /* now add a 2nd order upwind advection term to add a little asymmetry */
53           if (j>2) {
54             J = Ii-2*bs; v2 = 0.5*a; v1 = -2.0*a; v0 = 1.5*a;
55             CHKERRQ(MatSetValues(A,1,&Ii,1,&J,&v2,ADD_VALUES));
56           } else {
57             /* fall back to 1st order upwind */
58             v1 = -1.0*a; v0 = 1.0*a;
59           };
60           if (j>1) {J = Ii-1*bs; CHKERRQ(MatSetValues(A,1,&Ii,1,&J,&v1,ADD_VALUES));}
61           CHKERRQ(MatSetValues(A,1,&Ii,1,&Ii,&v0,ADD_VALUES));
62           a /= 10.; /* use a different velocity for the next component */
63           /* add a coupling to the previous and next components */
64           v = 0.5;
65           if (b>0) {J = Ii - 1; CHKERRQ(MatSetValues(A,1,&Ii,1,&J,&v,ADD_VALUES));}
66           if (b<bs-1) {J = Ii + 1; CHKERRQ(MatSetValues(A,1,&Ii,1,&J,&v,ADD_VALUES));}
67         }
68         /* make up some rhs */
69         CHKERRQ(VecSetValue(rhs, Ii, rhsval, INSERT_VALUES));
70         rhsval += 1.0;
71       }
72     }
73   }
74   CHKERRQ(MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY));
75   CHKERRQ(MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY));
76 
77   if (convert) { /* Test different Mat implementations */
78     Mat B;
79 
80     CHKERRQ(MatConvert(A,convname,MAT_INITIAL_MATRIX,&B));
81     CHKERRQ(MatDestroy(&A));
82     A    = B;
83   }
84 
85   CHKERRQ(VecAssemblyBegin(rhs));
86   CHKERRQ(VecAssemblyEnd(rhs));
87   /* set rhs to zero to simplify */
88   if (zerorhs) {
89     CHKERRQ(VecZeroEntries(rhs));
90   }
91 
92   if (nonlocalBC) {
93     /*version where boundary conditions are set by processes that don't necessarily own the nodes */
94     if (rank == 0) {
95       nboundary_nodes = size>m ? nlocal : m-size+nlocal;
96       CHKERRQ(PetscMalloc1(nboundary_nodes,&boundary_nodes));
97       k = 0;
98       for (i=size; i<m; i++,k++) {boundary_nodes[k] = n*i;};
99     } else if (rank < m) {
100       nboundary_nodes = nlocal+1;
101       CHKERRQ(PetscMalloc1(nboundary_nodes,&boundary_nodes));
102       boundary_nodes[0] = rank*n;
103       k = 1;
104     } else {
105       nboundary_nodes = nlocal;
106       CHKERRQ(PetscMalloc1(nboundary_nodes,&boundary_nodes));
107       k = 0;
108     }
109     for (j=nlocal*rank; j<nlocal*(rank+1); j++,k++) {boundary_nodes[k] = j;};
110   } else {
111     /*version where boundary conditions are set by the node owners only */
112     CHKERRQ(PetscMalloc1(m*n,&boundary_nodes));
113     k=0;
114     for (j=0; j<n; j++) {
115       Ii = j;
116       if (Ii>=rank*m*nlocal && Ii<(rank+1)*m*nlocal) boundary_nodes[k++] = Ii;
117     }
118     for (i=1; i<m; i++) {
119       Ii = n*i;
120       if (Ii>=rank*m*nlocal && Ii<(rank+1)*m*nlocal) boundary_nodes[k++] = Ii;
121     }
122     nboundary_nodes = k;
123   }
124 
125   CHKERRQ(VecDuplicate(rhs, &x));
126   CHKERRQ(VecZeroEntries(x));
127   CHKERRQ(PetscMalloc2(nboundary_nodes*bs,&boundary_indices,nboundary_nodes*bs,&boundary_values));
128   for (k=0; k<nboundary_nodes; k++) {
129     Ii = boundary_nodes[k]*bs;
130     v = 1.0*boundary_nodes[k];
131     for (b=0; b<bs; b++, Ii++) {
132       boundary_indices[k*bs+b] = Ii;
133       boundary_values[k*bs+b] = v;
134       CHKERRQ(PetscSynchronizedPrintf(PETSC_COMM_WORLD, "%d %" PetscInt_FMT " %f\n", rank, Ii, (double)PetscRealPart(v)));
135       v += 0.1;
136     }
137   }
138   CHKERRQ(PetscSynchronizedFlush(PETSC_COMM_WORLD, NULL));
139   CHKERRQ(VecSetValues(x, nboundary_nodes*bs, boundary_indices, boundary_values, INSERT_VALUES));
140   CHKERRQ(VecAssemblyBegin(x));
141   CHKERRQ(VecAssemblyEnd(x));
142 
143   /* We can check the rhs returned by MatZeroColumns by computing y=rhs-A*x  and overwriting the boundary entries with boundary values */
144   CHKERRQ(VecDuplicate(x, &y));
145   CHKERRQ(MatMult(A, x, y));
146   CHKERRQ(VecAYPX(y, -1.0, rhs));
147   for (k=0; k<nboundary_nodes*bs; k++) boundary_values[k] *= diag;
148   CHKERRQ(VecSetValues(y, nboundary_nodes*bs, boundary_indices, boundary_values, INSERT_VALUES));
149   CHKERRQ(VecAssemblyBegin(y));
150   CHKERRQ(VecAssemblyEnd(y));
151 
152   CHKERRQ(PetscPrintf(PETSC_COMM_WORLD, "*** Matrix A and vector x:\n"));
153   CHKERRQ(MatView(A, PETSC_VIEWER_STDOUT_WORLD));
154   CHKERRQ(VecView(x,PETSC_VIEWER_STDOUT_WORLD));
155 
156   CHKERRQ(MatZeroRowsColumns(A, nboundary_nodes*bs, boundary_indices, diag, x, rhs));
157   CHKERRQ(PetscPrintf(PETSC_COMM_WORLD, "*** Vector rhs returned by MatZeroRowsColumns\n"));
158   CHKERRQ(VecView(rhs,PETSC_VIEWER_STDOUT_WORLD));
159   CHKERRQ(VecAXPY(y, -1.0, rhs));
160   CHKERRQ(VecNorm(y, NORM_INFINITY, &norm));
161   if (norm > 1.0e-10) {
162     CHKERRQ(PetscPrintf(PETSC_COMM_WORLD, "*** Difference between rhs and y, inf-norm: %f\n", (double)norm));
163     CHKERRQ(VecView(y,PETSC_VIEWER_STDOUT_WORLD));
164     SETERRQ(PETSC_COMM_WORLD, PETSC_ERR_PLIB, "Bug in MatZeroRowsColumns");
165   }
166 
167   CHKERRQ(PetscFree(boundary_nodes));
168   CHKERRQ(PetscFree2(boundary_indices,boundary_values));
169   CHKERRQ(VecDestroy(&x));
170   CHKERRQ(VecDestroy(&y));
171   CHKERRQ(VecDestroy(&rhs));
172   CHKERRQ(MatDestroy(&A));
173 
174   ierr = PetscFinalize();
175   return ierr;
176 }
177 
178 /*TEST
179 
180    test:
181       diff_args: -j
182       suffix: 0
183 
184    test:
185       diff_args: -j
186       suffix: 1
187       nsize: 2
188 
189    test:
190       diff_args: -j
191       suffix: 10
192       nsize: 2
193       args: -bs 2 -nonlocal_bc
194 
195    test:
196       diff_args: -j
197       suffix: 11
198       nsize: 7
199       args: -bs 2 -nonlocal_bc
200 
201    test:
202       diff_args: -j
203       suffix: 12
204       args: -bs 2 -nonlocal_bc -mat_type baij
205 
206    test:
207       diff_args: -j
208       suffix: 13
209       nsize: 2
210       args: -bs 2 -nonlocal_bc -mat_type baij
211 
212    test:
213       diff_args: -j
214       suffix: 14
215       nsize: 7
216       args: -bs 2 -nonlocal_bc -mat_type baij
217 
218    test:
219       diff_args: -j
220       suffix: 2
221       nsize: 7
222 
223    test:
224       diff_args: -j
225       suffix: 3
226       args: -mat_type baij
227 
228    test:
229       diff_args: -j
230       suffix: 4
231       nsize: 2
232       args: -mat_type baij
233 
234    test:
235       diff_args: -j
236       suffix: 5
237       nsize: 7
238       args: -mat_type baij
239 
240    test:
241       diff_args: -j
242       suffix: 6
243       args: -bs 2 -mat_type baij
244 
245    test:
246       diff_args: -j
247       suffix: 7
248       nsize: 2
249       args: -bs 2 -mat_type baij
250 
251    test:
252       diff_args: -j
253       suffix: 8
254       nsize: 7
255       args: -bs 2 -mat_type baij
256 
257    test:
258       diff_args: -j
259       suffix: 9
260       args: -bs 2 -nonlocal_bc
261 
262    test:
263       diff_args: -j
264       suffix: 15
265       args: -bs 2 -nonlocal_bc -convname shell
266 
267    test:
268       diff_args: -j
269       suffix: 16
270       nsize: 2
271       args: -bs 2 -nonlocal_bc -convname shell
272 
273    test:
274       diff_args: -j
275       suffix: 17
276       args: -bs 2 -nonlocal_bc -convname dense
277 
278    testset:
279       diff_args: -j
280       suffix: full
281       nsize: {{1 3}separate output}
282       args: -diag {{0.12 -0.13}separate output} -convname {{aij shell baij}separate output} -zerorhs 0
283 
284    test:
285       diff_args: -j
286       requires: cuda
287       suffix: cusparse_1
288       nsize: 1
289       args: -diag {{0.12 -0.13}separate output} -convname {{seqaijcusparse mpiaijcusparse}separate output} -zerorhs 0 -mat_type {{seqaijcusparse mpiaijcusparse}separate output}
290 
291    test:
292       diff_args: -j
293       requires: cuda
294       suffix: cusparse_3
295       nsize: 3
296       args: -diag {{0.12 -0.13}separate output} -convname mpiaijcusparse -zerorhs 0 -mat_type mpiaijcusparse
297 
298 TEST*/
299