Actual source code: ex192.c

petsc-3.8.4 2018-03-24
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  2: static char help[] = "Tests MatSolve() and MatMatSolve() with MUMPS or MKL_PARDISO sequential solvers in Schur complement mode.\n\
  3: Example: mpiexec -n 1 ./ex192 -f <matrix binary file> -nrhs 4 -symmetric_solve -hermitian_solve -schur_ratio 0.3\n\n";

  5:  #include <petscmat.h>

  7: int main(int argc,char **args)
  8: {
  9:   Mat            A,RHS,C,F,X,S;
 10:   Vec            u,x,b;
 11:   Vec            xschur,bschur,uschur;
 12:   IS             is_schur;
 14:   PetscMPIInt    size;
 15:   PetscInt       isolver=0,size_schur,m,n,nfact,nsolve,nrhs;
 16:   PetscReal      norm,tol=PETSC_SQRT_MACHINE_EPSILON;
 17:   PetscRandom    rand;
 18:   PetscBool      data_provided,herm,symm,use_lu;
 19:   PetscReal      sratio = 5.1/12.;
 20:   PetscViewer    fd;              /* viewer */
 21:   char           solver[256];
 22:   char           file[PETSC_MAX_PATH_LEN]; /* input file name */

 24:   PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr;
 25:   MPI_Comm_size(PETSC_COMM_WORLD, &size);
 26:   if (size > 1) SETERRQ(PETSC_COMM_WORLD,1,"This is a uniprocessor test");
 27:   /* Determine which type of solver we want to test for */
 28:   herm = PETSC_FALSE;
 29:   symm = PETSC_FALSE;
 30:   PetscOptionsGetBool(NULL,NULL,"-symmetric_solve",&symm,NULL);
 31:   PetscOptionsGetBool(NULL,NULL,"-hermitian_solve",&herm,NULL);
 32:   if (herm) symm = PETSC_TRUE;

 34:   /* Determine file from which we read the matrix A */
 35:   PetscOptionsGetString(NULL,NULL,"-f",file,PETSC_MAX_PATH_LEN,&data_provided);
 36:   if (!data_provided) { /* get matrices from PETSc distribution */
 37:     sprintf(file,PETSC_DIR);
 38:     PetscStrcat(file,"/share/petsc/datafiles/matrices/");
 39:     if (symm) {
 40: #if defined (PETSC_USE_COMPLEX)
 41:       PetscStrcat(file,"hpd-complex-");
 42: #else
 43:       PetscStrcat(file,"spd-real-");
 44: #endif
 45:     } else {
 46: #if defined (PETSC_USE_COMPLEX)
 47:       PetscStrcat(file,"nh-complex-");
 48: #else
 49:       PetscStrcat(file,"ns-real-");
 50: #endif
 51:     }
 52: #if defined(PETSC_USE_64BIT_INDICES)
 53:     PetscStrcat(file,"int64-");
 54: #else
 55:     PetscStrcat(file,"int32-");
 56: #endif
 57: #if defined (PETSC_USE_REAL_SINGLE)
 58:     PetscStrcat(file,"float32");
 59: #else
 60:     PetscStrcat(file,"float64");
 61: #endif
 62:   }
 63:   /* Load matrix A */
 64:   PetscViewerBinaryOpen(PETSC_COMM_WORLD,file,FILE_MODE_READ,&fd);
 65:   MatCreate(PETSC_COMM_WORLD,&A);
 66:   MatLoad(A,fd);
 67:   PetscViewerDestroy(&fd);
 68:   MatGetSize(A,&m,&n);
 69:   if (m != n) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ, "This example is not intended for rectangular matrices (%d, %d)", m, n);

 71:   /* Create dense matrix C and X; C holds true solution with identical colums */
 72:   nrhs = 2;
 73:   PetscOptionsGetInt(NULL,NULL,"-nrhs",&nrhs,NULL);
 74:   MatCreate(PETSC_COMM_WORLD,&C);
 75:   MatSetSizes(C,m,PETSC_DECIDE,PETSC_DECIDE,nrhs);
 76:   MatSetType(C,MATDENSE);
 77:   MatSetFromOptions(C);
 78:   MatSetUp(C);

 80:   PetscRandomCreate(PETSC_COMM_WORLD,&rand);
 81:   PetscRandomSetFromOptions(rand);
 82:   MatSetRandom(C,rand);
 83:   MatDuplicate(C,MAT_DO_NOT_COPY_VALUES,&X);

 85:   /* Create vectors */
 86:   VecCreate(PETSC_COMM_WORLD,&x);
 87:   VecSetSizes(x,n,PETSC_DECIDE);
 88:   VecSetFromOptions(x);
 89:   VecDuplicate(x,&b);
 90:   VecDuplicate(x,&u); /* save the true solution */

 92:   PetscOptionsGetInt(NULL,NULL,"-solver",&isolver,NULL);
 93:   switch (isolver) {
 94: #if defined(PETSC_HAVE_MUMPS)
 95:     case 0:
 96:       PetscStrcpy(solver,MATSOLVERMUMPS);
 97:       break;
 98: #endif
 99: #if defined(PETSC_HAVE_MKL_PARDISO)
100:     case 1:
101:       PetscStrcpy(solver,MATSOLVERMKL_PARDISO);
102:       break;
103: #endif
104:     default:
105:       PetscStrcpy(solver,MATSOLVERPETSC);
106:       break;
107:   }

109: #if defined (PETSC_USE_COMPLEX)
110:   if (isolver == 0 && symm && !data_provided) { /* MUMPS (5.0.0) does not have support for hermitian matrices, so make them symmetric */
111:     PetscScalar im = PetscSqrtScalar((PetscScalar)-1.);
112:     PetscScalar val = -1.0;
113:     val = val + im;
114:     MatSetValue(A,1,0,val,INSERT_VALUES);
115:     MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
116:     MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
117:   }
118: #endif

120:   PetscOptionsGetReal(NULL,NULL,"-schur_ratio",&sratio,NULL);
121:   if (sratio < 0. || sratio > 1.) {
122:     SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ, "Invalid ratio for schur degrees of freedom %f", sratio);
123:   }
124:   size_schur = (PetscInt)(sratio*m);

126:   PetscPrintf(PETSC_COMM_SELF,"Solving with %s: nrhs %d, sym %d, herm %d, size schur %d, size mat %d\n",solver,nrhs,symm,herm,size_schur,m);

128:   /* Test LU/Cholesky Factorization */
129:   use_lu = PETSC_FALSE;
130:   if (!symm) use_lu = PETSC_TRUE;
131: #if defined (PETSC_USE_COMPLEX)
132:   if (isolver == 1) use_lu = PETSC_TRUE;
133: #endif

135:   if (herm && !use_lu) { /* test also conversion routines inside the solver packages */
136:     MatSetOption(A,MAT_SYMMETRIC,PETSC_TRUE);
137:     MatConvert(A,MATSEQSBAIJ,MAT_INPLACE_MATRIX,&A);
138:   }


141:   if (use_lu) {
142:     MatGetFactor(A,solver,MAT_FACTOR_LU,&F);
143:   } else {
144:     if (herm) {
145:       MatSetOption(A,MAT_SYMMETRIC,PETSC_TRUE);
146:       MatSetOption(A,MAT_SPD,PETSC_TRUE);
147:     } else {
148:       MatSetOption(A,MAT_SYMMETRIC,PETSC_TRUE);
149:       MatSetOption(A,MAT_SPD,PETSC_FALSE);
150:     }
151:     MatGetFactor(A,solver,MAT_FACTOR_CHOLESKY,&F);
152:   }
153:   ISCreateStride(PETSC_COMM_SELF,size_schur,m-size_schur,1,&is_schur);
154:   MatFactorSetSchurIS(F,is_schur);
155:   ISDestroy(&is_schur);
156:   if (use_lu) {
157:     MatLUFactorSymbolic(F,A,NULL,NULL,NULL);
158:   } else {
159:     MatCholeskyFactorSymbolic(F,A,NULL,NULL);
160:   }

162:   for (nfact = 0; nfact < 3; nfact++) {
163:     Mat AD;

165:     if (!nfact) {
166:       VecSetRandom(x,rand);
167:       if (symm && herm) {
168:         VecAbs(x);
169:       }
170:       MatDiagonalSet(A,x,ADD_VALUES);
171:     }
172:     if (use_lu) {
173:       MatLUFactorNumeric(F,A,NULL);
174:     } else {
175:       MatCholeskyFactorNumeric(F,A,NULL);
176:     }
177:     MatFactorCreateSchurComplement(F,&S,NULL);
178:     MatCreateVecs(S,&xschur,&bschur);
179:     VecDuplicate(xschur,&uschur);
180:     if (nfact == 1) {
181:       MatFactorInvertSchurComplement(F);
182:     }
183:     for (nsolve = 0; nsolve < 2; nsolve++) {
184:       VecSetRandom(x,rand);
185:       VecCopy(x,u);

187:       if (nsolve) {
188:         MatMult(A,x,b);
189:         MatSolve(F,b,x);
190:       } else {
191:         MatMultTranspose(A,x,b);
192:         MatSolveTranspose(F,b,x);
193:       }
194:       /* Check the error */
195:       VecAXPY(u,-1.0,x);  /* u <- (-1.0)x + u */
196:       VecNorm(u,NORM_2,&norm);
197:       if (norm > tol) {
198:         PetscReal resi;
199:         if (nsolve) {
200:           MatMult(A,x,u); /* u = A*x */
201:         } else {
202:           MatMultTranspose(A,x,u); /* u = A*x */
203:         }
204:         VecAXPY(u,-1.0,b);  /* u <- (-1.0)b + u */
205:         VecNorm(u,NORM_2,&resi);
206:         if (nsolve) {
207:           PetscPrintf(PETSC_COMM_SELF,"(f %d, s %d) MatSolve error: Norm of error %g, residual %f\n",nfact,nsolve,norm,resi);
208:         } else {
209:           PetscPrintf(PETSC_COMM_SELF,"(f %d, s %d) MatSolveTranspose error: Norm of error %g, residual %f\n",nfact,nsolve,norm,resi);
210:         }
211:       }
212:       VecSetRandom(xschur,rand);
213:       VecCopy(xschur,uschur);
214:       if (nsolve) {
215:         MatMult(S,xschur,bschur);
216:         MatFactorSolveSchurComplement(F,bschur,xschur);
217:       } else {
218:         MatMultTranspose(S,xschur,bschur);
219:         MatFactorSolveSchurComplementTranspose(F,bschur,xschur);
220:       }
221:       /* Check the error */
222:       VecAXPY(uschur,-1.0,xschur);  /* u <- (-1.0)x + u */
223:       VecNorm(uschur,NORM_2,&norm);
224:       if (norm > tol) {
225:         PetscReal resi;
226:         if (nsolve) {
227:           MatMult(S,xschur,uschur); /* u = A*x */
228:         } else {
229:           MatMultTranspose(S,xschur,uschur); /* u = A*x */
230:         }
231:         VecAXPY(uschur,-1.0,bschur);  /* u <- (-1.0)b + u */
232:         VecNorm(uschur,NORM_2,&resi);
233:         if (nsolve) {
234:           PetscPrintf(PETSC_COMM_SELF,"(f %d, s %d) MatFactorSolveSchurComplement error: Norm of error %g, residual %f\n",nfact,nsolve,norm,resi);
235:         } else {
236:           PetscPrintf(PETSC_COMM_SELF,"(f %d, s %d) MatFactorSolveSchurComplementTranspose error: Norm of error %g, residual %f\n",nfact,nsolve,norm,resi);
237:         }
238:       }
239:     }
240:     MatConvert(A,MATSEQAIJ,MAT_INITIAL_MATRIX,&AD);
241:     if (!nfact) {
242:       MatMatMult(AD,C,MAT_INITIAL_MATRIX,2.0,&RHS);
243:     } else {
244:       MatMatMult(AD,C,MAT_REUSE_MATRIX,2.0,&RHS);
245:     }
246:     MatDestroy(&AD);
247:     for (nsolve = 0; nsolve < 2; nsolve++) {
248:       MatMatSolve(F,RHS,X);

250:       /* Check the error */
251:       MatAXPY(X,-1.0,C,SAME_NONZERO_PATTERN);
252:       MatNorm(X,NORM_FROBENIUS,&norm);
253:       if (norm > tol) {
254:         PetscPrintf(PETSC_COMM_SELF,"(f %D, s %D) MatMatSolve: Norm of error %g\n",nfact,nsolve,norm);
255:       }
256:     }
257:     if (isolver == 0) {
258:       Mat spRHS,spRHST,RHST;

260:       MatTranspose(RHS,MAT_INITIAL_MATRIX,&RHST);
261:       MatConvert(RHST,MATSEQAIJ,MAT_INITIAL_MATRIX,&spRHST);
262:       MatCreateTranspose(spRHST,&spRHS);
263:       for (nsolve = 0; nsolve < 2; nsolve++) {
264:         MatMatSolve(F,spRHS,X);

266:         /* Check the error */
267:         MatAXPY(X,-1.0,C,SAME_NONZERO_PATTERN);
268:         MatNorm(X,NORM_FROBENIUS,&norm);
269:         if (norm > tol) {
270:           PetscPrintf(PETSC_COMM_SELF,"(f %D, s %D) sparse MatMatSolve: Norm of error %g\n",nfact,nsolve,norm);
271:         }
272:       }
273:       MatDestroy(&spRHST);
274:       MatDestroy(&spRHS);
275:       MatDestroy(&RHST);
276:     }
277:     MatDestroy(&S);
278:     VecDestroy(&xschur);
279:     VecDestroy(&bschur);
280:     VecDestroy(&uschur);
281:   }
282:   /* Free data structures */
283:   MatDestroy(&A);
284:   MatDestroy(&C);
285:   MatDestroy(&F);
286:   MatDestroy(&X);
287:   MatDestroy(&RHS);
288:   PetscRandomDestroy(&rand);
289:   VecDestroy(&x);
290:   VecDestroy(&b);
291:   VecDestroy(&u);
292:   PetscFinalize();
293:   return ierr;
294: }