Actual source code: test17.c
slepc-3.8.0 2017-10-20
1: /*
2: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
3: SLEPc - Scalable Library for Eigenvalue Problem Computations
4: Copyright (c) 2002-2017, Universitat Politecnica de Valencia, Spain
6: This file is part of SLEPc.
7: SLEPc is distributed under a 2-clause BSD license (see LICENSE).
8: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
9: */
11: static char help[] = "Test interface functions of spectrum-slicing Krylov-Schur.\n\n"
12: "This is based on ex12.c. The command line options are:\n"
13: " -n <n>, where <n> = number of grid subdivisions in x dimension.\n"
14: " -m <m>, where <m> = number of grid subdivisions in y dimension.\n\n";
16: #include <slepceps.h>
18: int main(int argc,char **argv)
19: {
20: Mat A,B; /* matrices */
21: Mat As,Bs; /* matrices distributed in subcommunicators */
22: Mat Au; /* matrix used to modify A on subcommunicators */
23: EPS eps; /* eigenproblem solver context */
24: ST st; /* spectral transformation context */
25: KSP ksp;
26: PC pc;
27: Vec v;
28: PetscMPIInt size,rank;
29: PetscInt N,n=35,m,Istart,Iend,II,nev,ncv,mpd,i,j,k,*inertias,npart,nval,start,nloc,nlocs,mlocs;
30: PetscBool flag,showinertia=PETSC_TRUE,lock,detect;
31: PetscReal int0,int1,*shifts,keep,*subint;
32: PetscScalar eval;
33: size_t count;
34: char vlist[4000];
37: SlepcInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr;
38: MPI_Comm_size(PETSC_COMM_WORLD,&size);
39: MPI_Comm_rank(PETSC_COMM_WORLD,&rank);
41: PetscOptionsGetBool(NULL,NULL,"-showinertia",&showinertia,NULL);
42: PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL);
43: PetscOptionsGetInt(NULL,NULL,"-m",&m,&flag);
44: if (!flag) m=n;
45: N = n*m;
46: PetscPrintf(PETSC_COMM_WORLD,"\nSpectrum-slicing test, N=%D (%Dx%D grid)\n\n",N,n,m);
48: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
49: Compute the matrices that define the eigensystem, Ax=kBx
50: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
52: MatCreate(PETSC_COMM_WORLD,&A);
53: MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,N,N);
54: MatSetFromOptions(A);
55: MatSetUp(A);
57: MatCreate(PETSC_COMM_WORLD,&B);
58: MatSetSizes(B,PETSC_DECIDE,PETSC_DECIDE,N,N);
59: MatSetFromOptions(B);
60: MatSetUp(B);
62: MatGetOwnershipRange(A,&Istart,&Iend);
63: for (II=Istart;II<Iend;II++) {
64: i = II/n; j = II-i*n;
65: if (i>0) { MatSetValue(A,II,II-n,-1.0,INSERT_VALUES); }
66: if (i<m-1) { MatSetValue(A,II,II+n,-1.0,INSERT_VALUES); }
67: if (j>0) { MatSetValue(A,II,II-1,-1.0,INSERT_VALUES); }
68: if (j<n-1) { MatSetValue(A,II,II+1,-1.0,INSERT_VALUES); }
69: MatSetValue(A,II,II,4.0,INSERT_VALUES);
70: MatSetValue(B,II,II,2.0,INSERT_VALUES);
71: }
72: if (Istart==0) {
73: MatSetValue(B,0,0,6.0,INSERT_VALUES);
74: MatSetValue(B,0,1,-1.0,INSERT_VALUES);
75: MatSetValue(B,1,0,-1.0,INSERT_VALUES);
76: MatSetValue(B,1,1,1.0,INSERT_VALUES);
77: }
79: MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
80: MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
81: MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);
82: MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);
84: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
85: Create the eigensolver and set various options
86: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
88: EPSCreate(PETSC_COMM_WORLD,&eps);
89: EPSSetOperators(eps,A,B);
90: EPSSetProblemType(eps,EPS_GHEP);
91: EPSSetType(eps,EPSKRYLOVSCHUR);
93: /*
94: Set interval and other settings for spectrum slicing
95: */
96: EPSSetWhichEigenpairs(eps,EPS_ALL);
97: int0 = 1.1; int1 = 1.3;
98: EPSSetInterval(eps,int0,int1);
99: EPSGetST(eps,&st);
100: STSetType(st,STSINVERT);
101: STGetKSP(st,&ksp);
102: KSPGetPC(ksp,&pc);
103: KSPSetType(ksp,KSPPREONLY);
104: PCSetType(pc,PCCHOLESKY);
106: /*
107: Test interface functions of Krylov-Schur solver
108: */
109: EPSKrylovSchurGetRestart(eps,&keep);
110: PetscPrintf(PETSC_COMM_WORLD," Restart parameter before changing = %g",(double)keep);
111: EPSKrylovSchurSetRestart(eps,0.4);
112: EPSKrylovSchurGetRestart(eps,&keep);
113: PetscPrintf(PETSC_COMM_WORLD," ... changed to %g\n",(double)keep);
115: EPSKrylovSchurGetDetectZeros(eps,&detect);
116: PetscPrintf(PETSC_COMM_WORLD," Detect zeros before changing = %d",(int)detect);
117: EPSKrylovSchurSetDetectZeros(eps,PETSC_TRUE);
118: EPSKrylovSchurGetDetectZeros(eps,&detect);
119: PetscPrintf(PETSC_COMM_WORLD," ... changed to %d\n",(int)detect);
121: EPSKrylovSchurGetLocking(eps,&lock);
122: PetscPrintf(PETSC_COMM_WORLD," Locking flag before changing = %d",(int)lock);
123: EPSKrylovSchurSetLocking(eps,PETSC_FALSE);
124: EPSKrylovSchurGetLocking(eps,&lock);
125: PetscPrintf(PETSC_COMM_WORLD," ... changed to %d\n",(int)lock);
127: EPSKrylovSchurGetDimensions(eps,&nev,&ncv,&mpd);
128: PetscPrintf(PETSC_COMM_WORLD," Sub-solve dimensions before changing = [%D,%D,%D]",nev,ncv,mpd);
129: EPSKrylovSchurSetDimensions(eps,30,60,60);
130: EPSKrylovSchurGetDimensions(eps,&nev,&ncv,&mpd);
131: PetscPrintf(PETSC_COMM_WORLD," ... changed to [%D,%D,%D]\n",nev,ncv,mpd);
133: if (size>1) {
134: EPSKrylovSchurSetPartitions(eps,size);
135: EPSKrylovSchurGetPartitions(eps,&npart);
136: PetscPrintf(PETSC_COMM_WORLD," Using %D partitions\n",npart);
138: PetscMalloc1(npart+1,&subint);
139: subint[0] = int0;
140: subint[npart] = int1;
141: for (i=1;i<npart;i++) subint[i] = int0+i*(int1-int0)/npart;
142: EPSKrylovSchurSetSubintervals(eps,subint);
143: PetscFree(subint);
144: EPSKrylovSchurGetSubintervals(eps,&subint);
145: PetscPrintf(PETSC_COMM_WORLD," Using sub-interval separations = ");
146: for (i=1;i<npart;i++) { PetscPrintf(PETSC_COMM_WORLD," %g",(double)subint[i]); }
147: PetscFree(subint);
148: PetscPrintf(PETSC_COMM_WORLD,"\n");
149: }
151: EPSSetFromOptions(eps);
153: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
154: Compute all eigenvalues in interval and display info
155: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
157: EPSSetUp(eps);
158: EPSKrylovSchurGetInertias(eps,&k,&shifts,&inertias);
159: PetscPrintf(PETSC_COMM_WORLD," Inertias after EPSSetUp:\n");
160: for (i=0;i<k;i++) {
161: PetscPrintf(PETSC_COMM_WORLD," .. %g (%D)\n",(double)shifts[i],inertias[i]);
162: }
163: PetscFree(shifts);
164: PetscFree(inertias);
166: EPSSolve(eps);
167: EPSGetDimensions(eps,&nev,NULL,NULL);
168: EPSGetInterval(eps,&int0,&int1);
169: PetscPrintf(PETSC_COMM_WORLD," Found %D eigenvalues in interval [%g,%g]\n",nev,(double)int0,(double)int1);
171: if (showinertia) {
172: EPSKrylovSchurGetInertias(eps,&k,&shifts,&inertias);
173: PetscPrintf(PETSC_COMM_WORLD," Used %D shifts (inertia):\n",k);
174: for (i=0;i<k;i++) {
175: PetscPrintf(PETSC_COMM_WORLD," .. %g (%D)\n",(double)shifts[i],inertias[i]);
176: }
177: PetscFree(shifts);
178: PetscFree(inertias);
179: }
181: EPSErrorView(eps,EPS_ERROR_RELATIVE,NULL);
183: if (size>1) {
184: EPSKrylovSchurGetSubcommInfo(eps,&k,&nval,&v);
185: start = 0;
186: for (i=0;i<nval;i++) {
187: EPSKrylovSchurGetSubcommPairs(eps,i,&eval,v);
188: PetscSNPrintfCount(vlist+start,4000-start,"%g ",&count,(double)PetscRealPart(eval));
189: start += count;
190: }
191: PetscSynchronizedPrintf(PETSC_COMM_WORLD," Process %d has worked in sub-interval %D, containing %D eigenvalues: %s\n",(int)rank,k,nval,vlist);
192: PetscSynchronizedFlush(PETSC_COMM_WORLD,PETSC_STDOUT);
193: VecDestroy(&v);
195: EPSKrylovSchurGetSubcommMats(eps,&As,&Bs);
196: MatGetLocalSize(A,&nloc,NULL);
197: MatGetLocalSize(As,&nlocs,&mlocs);
198: PetscSynchronizedPrintf(PETSC_COMM_WORLD," Process %d owns %D rows of the global matrices, and %D rows in the subcommunicator\n",(int)rank,nloc,nlocs);
199: PetscSynchronizedFlush(PETSC_COMM_WORLD,PETSC_STDOUT);
201: /* modify A on subcommunicators */
202: MatCreate(PetscObjectComm((PetscObject)As),&Au);
203: MatSetSizes(Au,nlocs,mlocs,N,N);
204: MatSetFromOptions(Au);
205: MatSetUp(Au);
206: MatGetOwnershipRange(Au,&Istart,&Iend);
207: for (II=Istart;II<Iend;II++) {
208: MatSetValue(Au,II,II,0.5,INSERT_VALUES);
209: }
210: MatAssemblyBegin(Au,MAT_FINAL_ASSEMBLY);
211: MatAssemblyEnd(Au,MAT_FINAL_ASSEMBLY);
212: EPSKrylovSchurUpdateSubcommMats(eps,1.0,-1.0,Au,0.0,0.0,NULL,DIFFERENT_NONZERO_PATTERN,PETSC_TRUE);
213: MatDestroy(&Au);
214: }
216: EPSDestroy(&eps);
217: MatDestroy(&A);
218: MatDestroy(&B);
219: SlepcFinalize();
220: return ierr;
221: }