Actual source code: ex2.c
slepc-3.17.1 2022-04-11
1: /*
2: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
3: SLEPc - Scalable Library for Eigenvalue Problem Computations
4: Copyright (c) 2002-, 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[] = "Standard symmetric eigenproblem corresponding to the Laplacian operator in 2 dimensions.\n\n"
12: "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; /* operator matrix */
21: EPS eps; /* eigenproblem solver context */
22: EPSType type;
23: PetscInt N,n=10,m,Istart,Iend,II,nev,i,j;
24: PetscBool flag,terse;
26: SlepcInitialize(&argc,&argv,(char*)0,help);
28: PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL);
29: PetscOptionsGetInt(NULL,NULL,"-m",&m,&flag);
30: if (!flag) m=n;
31: N = n*m;
32: PetscPrintf(PETSC_COMM_WORLD,"\n2-D Laplacian Eigenproblem, N=%" PetscInt_FMT " (%" PetscInt_FMT "x%" PetscInt_FMT " grid)\n\n",N,n,m);
34: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
35: Compute the operator matrix that defines the eigensystem, Ax=kx
36: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
38: MatCreate(PETSC_COMM_WORLD,&A);
39: MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,N,N);
40: MatSetFromOptions(A);
41: MatSetUp(A);
43: MatGetOwnershipRange(A,&Istart,&Iend);
44: for (II=Istart;II<Iend;II++) {
45: i = II/n; j = II-i*n;
46: if (i>0) MatSetValue(A,II,II-n,-1.0,INSERT_VALUES);
47: if (i<m-1) MatSetValue(A,II,II+n,-1.0,INSERT_VALUES);
48: if (j>0) MatSetValue(A,II,II-1,-1.0,INSERT_VALUES);
49: if (j<n-1) MatSetValue(A,II,II+1,-1.0,INSERT_VALUES);
50: MatSetValue(A,II,II,4.0,INSERT_VALUES);
51: }
53: MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
54: MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
56: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
57: Create the eigensolver and set various options
58: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
60: /*
61: Create eigensolver context
62: */
63: EPSCreate(PETSC_COMM_WORLD,&eps);
65: /*
66: Set operators. In this case, it is a standard eigenvalue problem
67: */
68: EPSSetOperators(eps,A,NULL);
69: EPSSetProblemType(eps,EPS_HEP);
71: /*
72: Set solver parameters at runtime
73: */
74: EPSSetFromOptions(eps);
76: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
77: Solve the eigensystem
78: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
80: EPSSolve(eps);
82: /*
83: Optional: Get some information from the solver and display it
84: */
85: EPSGetType(eps,&type);
86: PetscPrintf(PETSC_COMM_WORLD," Solution method: %s\n\n",type);
87: EPSGetDimensions(eps,&nev,NULL,NULL);
88: PetscPrintf(PETSC_COMM_WORLD," Number of requested eigenvalues: %" PetscInt_FMT "\n",nev);
90: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
91: Display solution and clean up
92: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
94: /* show detailed info unless -terse option is given by user */
95: PetscOptionsHasName(NULL,NULL,"-terse",&terse);
96: if (terse) EPSErrorView(eps,EPS_ERROR_RELATIVE,NULL);
97: else {
98: PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD,PETSC_VIEWER_ASCII_INFO_DETAIL);
99: EPSConvergedReasonView(eps,PETSC_VIEWER_STDOUT_WORLD);
100: EPSErrorView(eps,EPS_ERROR_RELATIVE,PETSC_VIEWER_STDOUT_WORLD);
101: PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD);
102: }
103: EPSDestroy(&eps);
104: MatDestroy(&A);
105: SlepcFinalize();
106: return 0;
107: }
109: /*TEST
111: testset:
112: args: -n 72 -eps_nev 4 -eps_ncv 20 -terse
113: output_file: output/ex2_1.out
114: requires: !single
115: test:
116: suffix: 1
117: test:
118: suffix: 2
119: args: -library_preload
121: testset:
122: args: -n 30 -eps_type ciss -eps_ciss_realmats -terse
123: requires: !single
124: output_file: output/ex2_ciss.out
125: filter: grep -v method
126: test:
127: suffix: ciss_1
128: nsize: 1
129: args: -rg_type interval -rg_interval_endpoints 1.1,1.25,-.1,.1
130: requires: complex
131: test:
132: suffix: ciss_1_hpddm
133: nsize: 1
134: args: -rg_type interval -rg_interval_endpoints 1.1,1.25 -st_ksp_type hpddm
135: requires: hpddm
136: test:
137: suffix: ciss_2
138: nsize: 2
139: args: -rg_type ellipse -rg_ellipse_center 1.175 -rg_ellipse_radius 0.075 -eps_ciss_partitions 2
140: test:
141: suffix: ciss_2_block
142: args: -rg_type ellipse -rg_ellipse_center 1.175 -rg_ellipse_radius 0.075 -eps_ciss_blocksize 3 -eps_ciss_moments 2
143: requires: complex !__float128
144: test:
145: suffix: ciss_2_hpddm
146: nsize: 2
147: args: -rg_type ellipse -rg_ellipse_center 1.175 -rg_ellipse_radius 0.075 -eps_ciss_partitions 2 -eps_ciss_ksp_type hpddm
148: requires: hpddm
149: test:
150: suffix: feast
151: args: -eps_type feast -eps_interval 1.1,1.25 -eps_ncv 64
152: requires: feast
154: testset:
155: args: -n 30 -m 30 -eps_interval 3.9,4.15 -terse
156: output_file: output/ex2_3.out
157: filter: grep -v Solution
158: requires: !single
159: test:
160: suffix: 3
161: args: -st_type sinvert -st_pc_type cholesky
162: test:
163: suffix: 3_evsl
164: args: -eps_type evsl -eps_evsl_slices 6
165: requires: evsl
167: testset:
168: args: -n 45 -m 46 -eps_interval 4.54,4.57 -eps_ncv 24 -terse
169: output_file: output/ex2_4.out
170: filter: grep -v Solution
171: requires: !single
172: timeoutfactor: 2
173: test:
174: suffix: 4
175: args: -st_type sinvert -st_pc_type cholesky
176: test:
177: suffix: 4_filter
178: args: -eps_type {{krylovschur subspace}} -st_type filter -st_filter_degree 200
179: requires: !__float128
180: test:
181: suffix: 4_filter_cuda
182: args: -eps_type {{krylovschur subspace}} -st_type filter -st_filter_degree 200 -mat_type aijcusparse
183: requires: cuda
184: test:
185: suffix: 4_evsl
186: args: -eps_type evsl
187: requires: evsl
189: TEST*/