Actual source code: ex5.c
petsc-3.7.3 2016-08-01
2: static char help[] = "Tests MatMult(), MatMultAdd(), MatMultTranspose().\n\
3: Also MatMultTransposeAdd(), MatScale(), MatGetDiagonal(), and MatDiagonalScale().\n\n";
5: #include <petscmat.h>
9: int main(int argc,char **args)
10: {
11: Mat C;
12: Vec s,u,w,x,y,z;
14: PetscInt i,j,m = 8,n,rstart,rend,vstart,vend;
15: PetscScalar one = 1.0,negone = -1.0,v,alpha=0.1;
16: PetscReal norm, tol = PETSC_SQRT_MACHINE_EPSILON;
17: PetscBool flg;
19: PetscInitialize(&argc,&args,(char*)0,help);
20: PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD,PETSC_VIEWER_ASCII_COMMON);
21: PetscOptionsGetInt(NULL,NULL,"-m",&m,NULL);
22: n = m;
23: PetscOptionsHasName(NULL,NULL,"-rectA",&flg);
24: if (flg) n += 2;
25: PetscOptionsHasName(NULL,NULL,"-rectB",&flg);
26: if (flg) n -= 2;
28: /* ---------- Assemble matrix and vectors ----------- */
30: MatCreate(PETSC_COMM_WORLD,&C);
31: MatSetSizes(C,PETSC_DECIDE,PETSC_DECIDE,m,n);
32: MatSetFromOptions(C);
33: MatSetUp(C);
34: MatGetOwnershipRange(C,&rstart,&rend);
35: VecCreate(PETSC_COMM_WORLD,&x);
36: VecSetSizes(x,PETSC_DECIDE,m);
37: VecSetFromOptions(x);
38: VecDuplicate(x,&z);
39: VecDuplicate(x,&w);
40: VecCreate(PETSC_COMM_WORLD,&y);
41: VecSetSizes(y,PETSC_DECIDE,n);
42: VecSetFromOptions(y);
43: VecDuplicate(y,&u);
44: VecDuplicate(y,&s);
45: VecGetOwnershipRange(y,&vstart,&vend);
47: /* Assembly */
48: for (i=rstart; i<rend; i++) {
49: v = 100*(i+1);
50: VecSetValues(z,1,&i,&v,INSERT_VALUES);
51: for (j=0; j<n; j++) {
52: v = 10*(i+1)+j+1;
53: MatSetValues(C,1,&i,1,&j,&v,INSERT_VALUES);
54: }
55: }
57: /* Flush off proc Vec values and do more assembly */
58: VecAssemblyBegin(z);
59: for (i=vstart; i<vend; i++) {
60: v = one*((PetscReal)i);
61: VecSetValues(y,1,&i,&v,INSERT_VALUES);
62: v = 100.0*i;
63: VecSetValues(u,1,&i,&v,INSERT_VALUES);
64: }
66: /* Flush off proc Mat values and do more assembly */
67: MatAssemblyBegin(C,MAT_FLUSH_ASSEMBLY);
68: for (i=rstart; i<rend; i++) {
69: for (j=0; j<n; j++) {
70: v = 10*(i+1)+j+1;
71: MatSetValues(C,1,&i,1,&j,&v,INSERT_VALUES);
72: }
73: }
74: /* Try overlap Coomunication with the next stage XXXSetValues */
75: VecAssemblyEnd(z);
76: MatAssemblyEnd(C,MAT_FLUSH_ASSEMBLY);
77: CHKMEMQ;
78: /* The Assembly for the second Stage */
79: MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY);
80: MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY);
81: VecAssemblyBegin(y);
82: VecAssemblyEnd(y);
83: MatScale(C,alpha);
84: VecAssemblyBegin(u);
85: VecAssemblyEnd(u);
87: /* ------------ Test MatMult(), MatMultAdd() ---------- */
89: PetscPrintf(PETSC_COMM_WORLD,"testing MatMult()\n");
90: CHKMEMQ;
91: MatMult(C,y,x);
92: CHKMEMQ;
93: VecView(x,PETSC_VIEWER_STDOUT_WORLD);
94: PetscPrintf(PETSC_COMM_WORLD,"testing MatMultAdd()\n");
95: MatMultAdd(C,y,z,w);
96: VecAXPY(x,one,z);
97: VecAXPY(x,negone,w);
98: VecNorm(x,NORM_2,&norm);
99: if (norm > tol) {
100: PetscPrintf(PETSC_COMM_WORLD,"Norm of error difference = %g\n",(double)norm);
101: }
103: /* ------- Test MatMultTranspose(), MatMultTransposeAdd() ------- */
105: for (i=rstart; i<rend; i++) {
106: v = one*((PetscReal)i);
107: VecSetValues(x,1,&i,&v,INSERT_VALUES);
108: }
109: VecAssemblyBegin(x);
110: VecAssemblyEnd(x);
111: PetscPrintf(PETSC_COMM_WORLD,"testing MatMultTranspose()\n");
112: MatMultTranspose(C,x,y);
113: VecView(y,PETSC_VIEWER_STDOUT_WORLD);
115: PetscPrintf(PETSC_COMM_WORLD,"testing MatMultTransposeAdd()\n");
116: MatMultTransposeAdd(C,x,u,s);
117: VecAXPY(y,one,u);
118: VecAXPY(y,negone,s);
119: VecNorm(y,NORM_2,&norm);
120: if (norm > tol) {
121: PetscPrintf(PETSC_COMM_WORLD,"Norm of error difference = %g\n",(double)norm);
122: }
124: /* -------------------- Test MatGetDiagonal() ------------------ */
126: PetscPrintf(PETSC_COMM_WORLD,"testing MatGetDiagonal(), MatDiagonalScale()\n");
127: MatView(C,PETSC_VIEWER_STDOUT_WORLD);
128: VecSet(x,one);
129: MatGetDiagonal(C,x);
130: VecView(x,PETSC_VIEWER_STDOUT_WORLD);
131: for (i=vstart; i<vend; i++) {
132: v = one*((PetscReal)(i+1));
133: VecSetValues(y,1,&i,&v,INSERT_VALUES);
134: }
136: /* -------------------- Test () MatDiagonalScale ------------------ */
137: PetscOptionsHasName(NULL,NULL,"-test_diagonalscale",&flg);
138: if (flg) {
139: MatDiagonalScale(C,x,y);
140: MatView(C,PETSC_VIEWER_STDOUT_WORLD);
141: }
142: /* Free data structures */
143: VecDestroy(&u); VecDestroy(&s);
144: VecDestroy(&w); VecDestroy(&x);
145: VecDestroy(&y); VecDestroy(&z);
146: MatDestroy(&C);
148: PetscFinalize();
149: return 0;
150: }