Actual source code: ex2.c
slepc-main 2025-01-19
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: EPSStop stop;
24: PetscReal thres;
25: PetscInt N,n=10,m,Istart,Iend,II,nev,i,j;
26: PetscBool flag,terse;
28: PetscFunctionBeginUser;
29: PetscCall(SlepcInitialize(&argc,&argv,NULL,help));
31: PetscCall(PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL));
32: PetscCall(PetscOptionsGetInt(NULL,NULL,"-m",&m,&flag));
33: if (!flag) m=n;
34: N = n*m;
35: PetscCall(PetscPrintf(PETSC_COMM_WORLD,"\n2-D Laplacian Eigenproblem, N=%" PetscInt_FMT " (%" PetscInt_FMT "x%" PetscInt_FMT " grid)\n\n",N,n,m));
37: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
38: Compute the operator matrix that defines the eigensystem, Ax=kx
39: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
41: PetscCall(MatCreate(PETSC_COMM_WORLD,&A));
42: PetscCall(MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,N,N));
43: PetscCall(MatSetFromOptions(A));
45: PetscCall(MatGetOwnershipRange(A,&Istart,&Iend));
46: for (II=Istart;II<Iend;II++) {
47: i = II/n; j = II-i*n;
48: if (i>0) PetscCall(MatSetValue(A,II,II-n,-1.0,INSERT_VALUES));
49: if (i<m-1) PetscCall(MatSetValue(A,II,II+n,-1.0,INSERT_VALUES));
50: if (j>0) PetscCall(MatSetValue(A,II,II-1,-1.0,INSERT_VALUES));
51: if (j<n-1) PetscCall(MatSetValue(A,II,II+1,-1.0,INSERT_VALUES));
52: PetscCall(MatSetValue(A,II,II,4.0,INSERT_VALUES));
53: }
55: PetscCall(MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY));
56: PetscCall(MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY));
58: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
59: Create the eigensolver and set various options
60: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
62: /*
63: Create eigensolver context
64: */
65: PetscCall(EPSCreate(PETSC_COMM_WORLD,&eps));
67: /*
68: Set operators. In this case, it is a standard eigenvalue problem
69: */
70: PetscCall(EPSSetOperators(eps,A,NULL));
71: PetscCall(EPSSetProblemType(eps,EPS_HEP));
73: /*
74: Set solver parameters at runtime
75: */
76: PetscCall(EPSSetFromOptions(eps));
78: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
79: Solve the eigensystem
80: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
82: PetscCall(EPSSolve(eps));
84: /*
85: Optional: Get some information from the solver and display it
86: */
87: PetscCall(EPSGetType(eps,&type));
88: PetscCall(PetscPrintf(PETSC_COMM_WORLD," Solution method: %s\n\n",type));
89: PetscCall(EPSGetStoppingTest(eps,&stop));
90: if (stop!=EPS_STOP_THRESHOLD) {
91: PetscCall(EPSGetDimensions(eps,&nev,NULL,NULL));
92: PetscCall(PetscPrintf(PETSC_COMM_WORLD," Number of requested eigenvalues: %" PetscInt_FMT "\n",nev));
93: } else {
94: PetscCall(EPSGetThreshold(eps,&thres,NULL));
95: PetscCall(PetscPrintf(PETSC_COMM_WORLD," Using threshold: %.4g\n",(double)thres));
96: }
98: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
99: Display solution and clean up
100: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
102: /* show detailed info unless -terse option is given by user */
103: PetscCall(PetscOptionsHasName(NULL,NULL,"-terse",&terse));
104: if (terse) PetscCall(EPSErrorView(eps,EPS_ERROR_RELATIVE,NULL));
105: else {
106: PetscCall(PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD,PETSC_VIEWER_ASCII_INFO_DETAIL));
107: PetscCall(EPSConvergedReasonView(eps,PETSC_VIEWER_STDOUT_WORLD));
108: PetscCall(EPSErrorView(eps,EPS_ERROR_RELATIVE,PETSC_VIEWER_STDOUT_WORLD));
109: PetscCall(PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD));
110: }
111: PetscCall(EPSDestroy(&eps));
112: PetscCall(MatDestroy(&A));
113: PetscCall(SlepcFinalize());
114: return 0;
115: }
117: /*TEST
119: testset:
120: args: -n 72 -eps_nev 4 -eps_ncv 20 -terse
121: output_file: output/ex2_1.out
122: requires: !single
123: test:
124: suffix: 1
125: test:
126: suffix: 2
127: requires: defined(PETSC_HAVE_DYNAMIC_LIBRARIES) defined(PETSC_USE_SHARED_LIBRARIES)
128: args: -library_preload
130: testset:
131: args: -n 30 -eps_type ciss -eps_ciss_realmats -terse
132: requires: !single
133: output_file: output/ex2_ciss.out
134: filter: grep -v method
135: test:
136: suffix: ciss_1
137: nsize: 1
138: args: -rg_type interval -rg_interval_endpoints 1.1,1.25,-.1,.1
139: requires: complex
140: test:
141: suffix: ciss_1_hpddm
142: nsize: 1
143: args: -rg_type interval -rg_interval_endpoints 1.1,1.25 -st_ksp_type hpddm
144: requires: hpddm
145: test:
146: suffix: ciss_2
147: nsize: 2
148: args: -rg_type ellipse -rg_ellipse_center 1.175 -rg_ellipse_radius 0.075 -eps_ciss_partitions 2
149: test:
150: suffix: ciss_2_block
151: args: -rg_type ellipse -rg_ellipse_center 1.175 -rg_ellipse_radius 0.075 -eps_ciss_blocksize 3 -eps_ciss_moments 2
152: requires: complex !__float128
153: test:
154: suffix: ciss_2_hpddm
155: nsize: 2
156: args: -rg_type ellipse -rg_ellipse_center 1.175 -rg_ellipse_radius 0.075 -eps_ciss_partitions 2 -eps_ciss_ksp_type hpddm
157: requires: hpddm
158: test:
159: suffix: feast
160: args: -eps_type feast -eps_interval 1.1,1.25 -eps_ncv 64 -options_left 0
161: requires: feast
163: testset:
164: args: -n 30 -m 30 -eps_interval 3.9,4.15 -terse
165: output_file: output/ex2_3.out
166: filter: grep -v Solution
167: requires: !single
168: test:
169: suffix: 3
170: args: -st_type sinvert -st_pc_type cholesky
171: test:
172: suffix: 3_evsl
173: args: -eps_type evsl -eps_evsl_slices 6
174: requires: evsl
176: testset:
177: args: -n 45 -m 46 -eps_interval 4.54,4.57 -eps_ncv 24 -terse
178: output_file: output/ex2_4.out
179: filter: grep -v Solution
180: requires: !single
181: timeoutfactor: 2
182: test:
183: suffix: 4
184: args: -st_type sinvert -st_pc_type cholesky
185: test:
186: suffix: 4_filter
187: args: -eps_type {{krylovschur subspace}} -st_type filter -st_filter_degree 200
188: requires: !__float128
189: test:
190: suffix: 4_filter_cuda
191: args: -eps_type {{krylovschur subspace}} -st_type filter -st_filter_degree 200 -mat_type aijcusparse
192: requires: cuda
193: test:
194: suffix: 4_filter_hip
195: args: -eps_type {{krylovschur subspace}} -st_type filter -st_filter_degree 200 -mat_type aijhipsparse
196: requires: hip
197: test:
198: suffix: 4_evsl
199: args: -eps_type evsl
200: requires: evsl
202: test:
203: args: -n 25 -m 24 -eps_threshold_absolute .25 -eps_smallest_magnitude -eps_ncv 10 -terse
204: suffix: 5
205: requires: !single
207: testset:
208: args: -n 25 -m 24 -st_type sinvert -terse
209: requires: double
210: test:
211: suffix: 6
212: args: -eps_threshold_absolute .15 -eps_target 0.01
213: test:
214: suffix: 6_rel_large
215: args: -eps_threshold_relative .98 -eps_target 8
216: test:
217: suffix: 6_rel_small
218: args: -eps_threshold_relative 3
220: TEST*/