Actual source code: ex27.c
slepc-3.18.2 2023-01-26
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[] = "Simple nonlinear eigenproblem using the NLEIGS solver.\n\n"
12: "The command line options are:\n"
13: " -n <n>, where <n> = matrix dimension.\n"
14: " -split <0/1>, to select the split form in the problem definition (enabled by default)\n";
16: /*
17: Solve T(lambda)x=0 using NLEIGS solver
18: with T(lambda) = -D+sqrt(lambda)*I
19: where D is the Laplacian operator in 1 dimension
20: and with the interpolation interval [.01,16]
21: */
23: #include <slepcnep.h>
25: /*
26: User-defined routines
27: */
28: PetscErrorCode FormFunction(NEP,PetscScalar,Mat,Mat,void*);
29: PetscErrorCode FormJacobian(NEP,PetscScalar,Mat,void*);
30: PetscErrorCode ComputeSingularities(NEP,PetscInt*,PetscScalar*,void*);
32: int main(int argc,char **argv)
33: {
34: NEP nep; /* nonlinear eigensolver context */
35: Mat F,J,A[2];
36: NEPType type;
37: PetscInt n=100,nev,Istart,Iend,i;
38: PetscBool terse,split=PETSC_TRUE;
39: RG rg;
40: FN f[2];
41: PetscScalar coeffs;
44: SlepcInitialize(&argc,&argv,(char*)0,help);
45: PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL);
46: PetscOptionsGetBool(NULL,NULL,"-split",&split,NULL);
47: PetscPrintf(PETSC_COMM_WORLD,"\nSquare root eigenproblem, n=%" PetscInt_FMT "%s\n\n",n,split?" (in split form)":"");
49: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
50: Create nonlinear eigensolver context
51: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
53: NEPCreate(PETSC_COMM_WORLD,&nep);
55: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
56: Select the NLEIGS solver and set required options for it
57: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
59: NEPSetType(nep,NEPNLEIGS);
60: NEPNLEIGSSetSingularitiesFunction(nep,ComputeSingularities,NULL);
61: NEPGetRG(nep,&rg);
62: RGSetType(rg,RGINTERVAL);
63: #if defined(PETSC_USE_COMPLEX)
64: RGIntervalSetEndpoints(rg,0.01,16.0,-0.001,0.001);
65: #else
66: RGIntervalSetEndpoints(rg,0.01,16.0,0,0);
67: #endif
68: NEPSetTarget(nep,1.1);
70: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
71: Define the nonlinear problem
72: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
74: if (split) {
75: /*
76: Create matrices for the split form
77: */
78: MatCreate(PETSC_COMM_WORLD,&A[0]);
79: MatSetSizes(A[0],PETSC_DECIDE,PETSC_DECIDE,n,n);
80: MatSetFromOptions(A[0]);
81: MatSetUp(A[0]);
82: MatGetOwnershipRange(A[0],&Istart,&Iend);
83: for (i=Istart;i<Iend;i++) {
84: if (i>0) MatSetValue(A[0],i,i-1,1.0,INSERT_VALUES);
85: if (i<n-1) MatSetValue(A[0],i,i+1,1.0,INSERT_VALUES);
86: MatSetValue(A[0],i,i,-2.0,INSERT_VALUES);
87: }
88: MatAssemblyBegin(A[0],MAT_FINAL_ASSEMBLY);
89: MatAssemblyEnd(A[0],MAT_FINAL_ASSEMBLY);
91: MatCreateConstantDiagonal(PETSC_COMM_WORLD,PETSC_DECIDE,PETSC_DECIDE,n,n,1.0,&A[1]);
93: /*
94: Define functions for the split form
95: */
96: FNCreate(PETSC_COMM_WORLD,&f[0]);
97: FNSetType(f[0],FNRATIONAL);
98: coeffs = 1.0;
99: FNRationalSetNumerator(f[0],1,&coeffs);
100: FNCreate(PETSC_COMM_WORLD,&f[1]);
101: FNSetType(f[1],FNSQRT);
102: NEPSetSplitOperator(nep,2,A,f,SUBSET_NONZERO_PATTERN);
104: } else {
105: /*
106: Callback form: create matrix and set Function evaluation routine
107: */
108: MatCreate(PETSC_COMM_WORLD,&F);
109: MatSetSizes(F,PETSC_DECIDE,PETSC_DECIDE,n,n);
110: MatSetFromOptions(F);
111: MatSeqAIJSetPreallocation(F,3,NULL);
112: MatMPIAIJSetPreallocation(F,3,NULL,1,NULL);
113: MatSetUp(F);
114: NEPSetFunction(nep,F,F,FormFunction,NULL);
116: MatCreate(PETSC_COMM_WORLD,&J);
117: MatSetSizes(J,PETSC_DECIDE,PETSC_DECIDE,n,n);
118: MatSetFromOptions(J);
119: MatSeqAIJSetPreallocation(J,1,NULL);
120: MatMPIAIJSetPreallocation(J,1,NULL,1,NULL);
121: MatSetUp(J);
122: NEPSetJacobian(nep,J,FormJacobian,NULL);
123: }
125: /*
126: Set solver parameters at runtime
127: */
128: NEPSetFromOptions(nep);
130: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
131: Solve the eigensystem
132: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
133: NEPSolve(nep);
134: NEPGetType(nep,&type);
135: PetscPrintf(PETSC_COMM_WORLD," Solution method: %s\n",type);
136: NEPGetDimensions(nep,&nev,NULL,NULL);
137: PetscPrintf(PETSC_COMM_WORLD," Number of requested eigenvalues: %" PetscInt_FMT "\n",nev);
139: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
140: Display solution and clean up
141: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
143: /* show detailed info unless -terse option is given by user */
144: PetscOptionsHasName(NULL,NULL,"-terse",&terse);
145: if (terse) NEPErrorView(nep,NEP_ERROR_BACKWARD,NULL);
146: else {
147: PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD,PETSC_VIEWER_ASCII_INFO_DETAIL);
148: NEPConvergedReasonView(nep,PETSC_VIEWER_STDOUT_WORLD);
149: NEPErrorView(nep,NEP_ERROR_BACKWARD,PETSC_VIEWER_STDOUT_WORLD);
150: PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD);
151: }
152: NEPDestroy(&nep);
153: if (split) {
154: MatDestroy(&A[0]);
155: MatDestroy(&A[1]);
156: FNDestroy(&f[0]);
157: FNDestroy(&f[1]);
158: } else {
159: MatDestroy(&F);
160: MatDestroy(&J);
161: }
162: SlepcFinalize();
163: return 0;
164: }
166: /* ------------------------------------------------------------------- */
167: /*
168: FormFunction - Computes Function matrix T(lambda)
169: */
170: PetscErrorCode FormFunction(NEP nep,PetscScalar lambda,Mat fun,Mat B,void *ctx)
171: {
172: PetscInt i,n,col[3],Istart,Iend;
173: PetscBool FirstBlock=PETSC_FALSE,LastBlock=PETSC_FALSE;
174: PetscScalar value[3],t;
177: /*
178: Compute Function entries and insert into matrix
179: */
180: t = PetscSqrtScalar(lambda);
181: MatGetSize(fun,&n,NULL);
182: MatGetOwnershipRange(fun,&Istart,&Iend);
183: if (Istart==0) FirstBlock=PETSC_TRUE;
184: if (Iend==n) LastBlock=PETSC_TRUE;
185: value[0]=1.0; value[1]=t-2.0; value[2]=1.0;
186: for (i=(FirstBlock? Istart+1: Istart); i<(LastBlock? Iend-1: Iend); i++) {
187: col[0]=i-1; col[1]=i; col[2]=i+1;
188: MatSetValues(fun,1,&i,3,col,value,INSERT_VALUES);
189: }
190: if (LastBlock) {
191: i=n-1; col[0]=n-2; col[1]=n-1;
192: MatSetValues(fun,1,&i,2,col,value,INSERT_VALUES);
193: }
194: if (FirstBlock) {
195: i=0; col[0]=0; col[1]=1; value[0]=t-2.0; value[1]=1.0;
196: MatSetValues(fun,1,&i,2,col,value,INSERT_VALUES);
197: }
199: /*
200: Assemble matrix
201: */
202: MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);
203: MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);
204: if (fun != B) {
205: MatAssemblyBegin(fun,MAT_FINAL_ASSEMBLY);
206: MatAssemblyEnd(fun,MAT_FINAL_ASSEMBLY);
207: }
208: return 0;
209: }
211: /* ------------------------------------------------------------------- */
212: /*
213: FormJacobian - Computes Jacobian matrix T'(lambda)
214: */
215: PetscErrorCode FormJacobian(NEP nep,PetscScalar lambda,Mat jac,void *ctx)
216: {
217: Vec d;
220: MatCreateVecs(jac,&d,NULL);
221: VecSet(d,0.5/PetscSqrtScalar(lambda));
222: MatDiagonalSet(jac,d,INSERT_VALUES);
223: VecDestroy(&d);
224: return 0;
225: }
227: /* ------------------------------------------------------------------- */
228: /*
229: ComputeSingularities - Computes maxnp points (at most) in the complex plane where
230: the function T(.) is not analytic.
232: In this case, we discretize the singularity region (-inf,0)~(-10e+6,-10e-6)
233: */
234: PetscErrorCode ComputeSingularities(NEP nep,PetscInt *maxnp,PetscScalar *xi,void *pt)
235: {
236: PetscReal h;
237: PetscInt i;
240: h = 11.0/(*maxnp-1);
241: xi[0] = -1e-5; xi[*maxnp-1] = -1e+6;
242: for (i=1;i<*maxnp-1;i++) xi[i] = -PetscPowReal(10,-5+h*i);
243: return 0;
244: }
246: /*TEST
248: testset:
249: args: -nep_nev 3 -terse
250: output_file: output/ex27_1.out
251: requires: !single
252: filter: sed -e "s/[+-]0\.0*i//g"
253: test:
254: suffix: 1
255: args: -nep_nleigs_interpolation_degree 90
256: test:
257: suffix: 3
258: args: -nep_tol 1e-8 -nep_nleigs_rk_shifts 1.06,1.1,1.12,1.15 -nep_conv_norm -nep_nleigs_interpolation_degree 20
259: test:
260: suffix: 5
261: args: -mat_type aijcusparse
262: requires: cuda
264: testset:
265: args: -split 0 -nep_nev 3 -terse
266: output_file: output/ex27_2.out
267: filter: sed -e "s/[+-]0\.0*i//g"
268: test:
269: suffix: 2
270: args: -nep_nleigs_interpolation_degree 90
271: requires: !single
272: test:
273: suffix: 4
274: args: -nep_nleigs_rk_shifts 1.06,1.1,1.12,1.15 -nep_nleigs_interpolation_degree 20
275: requires: double
276: test:
277: suffix: 6
278: args: -mat_type aijcusparse
279: requires: cuda !single
281: testset:
282: args: -split 0 -nep_type ciss -nep_ciss_extraction {{ritz hankel caa}} -rg_type ellipse -rg_ellipse_center 8 -rg_ellipse_radius .7 -nep_ciss_moments 4 -rg_ellipse_vscale 0.1 -terse
283: requires: complex !single
284: output_file: output/ex27_7.out
285: timeoutfactor: 2
286: test:
287: suffix: 7
288: test:
289: suffix: 7_par
290: nsize: 2
291: args: -nep_ciss_partitions 2
293: testset:
294: args: -nep_type ciss -rg_type ellipse -rg_ellipse_center 8 -rg_ellipse_radius .7 -rg_ellipse_vscale 0.1 -terse
295: requires: complex
296: filter: sed -e "s/ (in split form)//" | sed -e "s/56925/56924/" | sed -e "s/60753/60754/" | sed -e "s/92630/92629/" | sed -e "s/24705/24706/"
297: output_file: output/ex27_7.out
298: timeoutfactor: 2
299: test:
300: suffix: 8
301: test:
302: suffix: 8_parallel
303: nsize: 4
304: args: -nep_ciss_partitions 4 -ds_parallel distributed
305: test:
306: suffix: 8_hpddm
307: args: -nep_ciss_ksp_type hpddm
308: requires: hpddm
310: test:
311: suffix: 9
312: args: -nep_nev 4 -n 20 -terse
313: requires: !single
314: filter: sed -e "s/[+-]0\.0*i//g"
316: TEST*/