Actual source code: ex2.c
slepc-3.21.0 2024-03-30
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: PetscFunctionBeginUser;
27: PetscCall(SlepcInitialize(&argc,&argv,(char*)0,help));
29: PetscCall(PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL));
30: PetscCall(PetscOptionsGetInt(NULL,NULL,"-m",&m,&flag));
31: if (!flag) m=n;
32: N = n*m;
33: PetscCall(PetscPrintf(PETSC_COMM_WORLD,"\n2-D Laplacian Eigenproblem, N=%" PetscInt_FMT " (%" PetscInt_FMT "x%" PetscInt_FMT " grid)\n\n",N,n,m));
35: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
36: Compute the operator matrix that defines the eigensystem, Ax=kx
37: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
39: PetscCall(MatCreate(PETSC_COMM_WORLD,&A));
40: PetscCall(MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,N,N));
41: PetscCall(MatSetFromOptions(A));
43: PetscCall(MatGetOwnershipRange(A,&Istart,&Iend));
44: for (II=Istart;II<Iend;II++) {
45: i = II/n; j = II-i*n;
46: if (i>0) PetscCall(MatSetValue(A,II,II-n,-1.0,INSERT_VALUES));
47: if (i<m-1) PetscCall(MatSetValue(A,II,II+n,-1.0,INSERT_VALUES));
48: if (j>0) PetscCall(MatSetValue(A,II,II-1,-1.0,INSERT_VALUES));
49: if (j<n-1) PetscCall(MatSetValue(A,II,II+1,-1.0,INSERT_VALUES));
50: PetscCall(MatSetValue(A,II,II,4.0,INSERT_VALUES));
51: }
53: PetscCall(MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY));
54: PetscCall(MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY));
56: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
57: Create the eigensolver and set various options
58: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
60: /*
61: Create eigensolver context
62: */
63: PetscCall(EPSCreate(PETSC_COMM_WORLD,&eps));
65: /*
66: Set operators. In this case, it is a standard eigenvalue problem
67: */
68: PetscCall(EPSSetOperators(eps,A,NULL));
69: PetscCall(EPSSetProblemType(eps,EPS_HEP));
71: /*
72: Set solver parameters at runtime
73: */
74: PetscCall(EPSSetFromOptions(eps));
76: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
77: Solve the eigensystem
78: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
80: PetscCall(EPSSolve(eps));
82: /*
83: Optional: Get some information from the solver and display it
84: */
85: PetscCall(EPSGetType(eps,&type));
86: PetscCall(PetscPrintf(PETSC_COMM_WORLD," Solution method: %s\n\n",type));
87: PetscCall(EPSGetDimensions(eps,&nev,NULL,NULL));
88: PetscCall(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: PetscCall(PetscOptionsHasName(NULL,NULL,"-terse",&terse));
96: if (terse) PetscCall(EPSErrorView(eps,EPS_ERROR_RELATIVE,NULL));
97: else {
98: PetscCall(PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD,PETSC_VIEWER_ASCII_INFO_DETAIL));
99: PetscCall(EPSConvergedReasonView(eps,PETSC_VIEWER_STDOUT_WORLD));
100: PetscCall(EPSErrorView(eps,EPS_ERROR_RELATIVE,PETSC_VIEWER_STDOUT_WORLD));
101: PetscCall(PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD));
102: }
103: PetscCall(EPSDestroy(&eps));
104: PetscCall(MatDestroy(&A));
105: PetscCall(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 -options_left 0
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*/