Actual source code: evsl.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: */
10: /*
11: This file implements a wrapper to eigensolvers in EVSL.
12: */
14: #include <slepc/private/epsimpl.h>
15: #include <evsl.h>
17: #define PetscCallEVSL(func, ...) do { \
18: PetscStackPushExternal(PetscStringize(func)); \
19: int evsl_ierr_ = func(__VA_ARGS__); \
20: PetscStackPop; \
21: PetscCheck(!evsl_ierr_,PETSC_COMM_SELF,PETSC_ERR_LIB,"Error calling %s: error code %d",PetscStringize(func(__VA_ARGS__)),evsl_ierr_); \
22: } while (0)
24: typedef struct {
25: PetscBool initialized;
26: Mat A; /* problem matrix */
27: Vec x,y; /* auxiliary vectors */
28: PetscReal *sli; /* slice bounds */
29: PetscInt nev; /* approximate number of wanted eigenvalues in each slice */
30: PetscLayout map; /* used to distribute slices among MPI processes */
31: PetscBool estimrange; /* the filter range was not set by the user */
32: /* user parameters */
33: PetscInt nslices; /* number of slices */
34: PetscReal lmin,lmax; /* numerical range (min and max eigenvalue) */
35: EPSEVSLDOSMethod dos; /* DOS method, either KPM or Lanczos */
36: PetscInt nvec; /* number of sample vectors used for DOS */
37: PetscInt deg; /* polynomial degree used for DOS (KPM only) */
38: PetscInt steps; /* number of Lanczos steps used for DOS (Lanczos only) */
39: PetscInt npoints; /* number of sample points used for DOS (Lanczos only) */
40: PetscInt max_deg; /* maximum degree allowed for the polynomial */
41: PetscReal thresh; /* threshold for accepting polynomial */
42: EPSEVSLDamping damping; /* type of damping (for polynomial and for DOS-KPM) */
43: } EPS_EVSL;
45: static void AMatvec_EVSL(double *xa,double *ya,void *data)
46: {
47: EPS_EVSL *ctx = (EPS_EVSL*)data;
48: Vec x = ctx->x,y = ctx->y;
49: Mat A = ctx->A;
51: PetscFunctionBegin;
52: PetscCallAbort(PetscObjectComm((PetscObject)A),VecPlaceArray(x,(PetscScalar*)xa));
53: PetscCallAbort(PetscObjectComm((PetscObject)A),VecPlaceArray(y,(PetscScalar*)ya));
54: PetscCallAbort(PetscObjectComm((PetscObject)A),MatMult(A,x,y));
55: PetscCallAbort(PetscObjectComm((PetscObject)A),VecResetArray(x));
56: PetscCallAbort(PetscObjectComm((PetscObject)A),VecResetArray(y));
57: PetscFunctionReturnVoid();
58: }
60: static PetscErrorCode EPSSetUp_EVSL(EPS eps)
61: {
62: EPS_EVSL *ctx = (EPS_EVSL*)eps->data;
63: PetscMPIInt size,rank;
64: PetscBool isshift;
65: PetscScalar *vinit;
66: PetscReal *mu,ecount,xintv[4],*xdos,*ydos;
67: Vec v0;
68: Mat A;
69: PetscRandom rnd;
71: PetscFunctionBegin;
72: EPSCheckStandard(eps);
73: EPSCheckHermitian(eps);
74: PetscCall(PetscObjectTypeCompare((PetscObject)eps->st,STSHIFT,&isshift));
75: PetscCheck(isshift,PetscObjectComm((PetscObject)eps),PETSC_ERR_SUP,"This solver does not support spectral transformations");
77: if (ctx->initialized) EVSLFinish();
78: EVSLStart();
79: ctx->initialized=PETSC_TRUE;
81: /* get number of slices per process */
82: PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)eps),&size));
83: PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)eps),&rank));
84: if (!ctx->nslices) ctx->nslices = size;
85: PetscCall(PetscLayoutDestroy(&ctx->map));
86: PetscCall(PetscLayoutCreateFromSizes(PetscObjectComm((PetscObject)eps),PETSC_DECIDE,ctx->nslices,1,&ctx->map));
88: /* get matrix and prepare auxiliary vectors */
89: PetscCall(MatDestroy(&ctx->A));
90: PetscCall(STGetMatrix(eps->st,0,&A));
91: if (size==1) {
92: PetscCall(PetscObjectReference((PetscObject)A));
93: ctx->A = A;
94: } else PetscCall(MatCreateRedundantMatrix(A,0,PETSC_COMM_SELF,MAT_INITIAL_MATRIX,&ctx->A));
95: SetAMatvec(eps->n,&AMatvec_EVSL,(void*)ctx);
96: if (!ctx->x) PetscCall(MatCreateVecsEmpty(ctx->A,&ctx->x,&ctx->y));
97: EPSCheckUnsupported(eps,EPS_FEATURE_ARBITRARY | EPS_FEATURE_REGION | EPS_FEATURE_STOPPING);
98: EPSCheckIgnored(eps,EPS_FEATURE_EXTRACTION | EPS_FEATURE_CONVERGENCE);
100: if (!eps->which) eps->which=EPS_ALL;
101: PetscCheck(eps->which==EPS_ALL && eps->inta!=eps->intb,PetscObjectComm((PetscObject)eps),PETSC_ERR_SUP,"This solver requires setting an interval with EPSSetInterval()");
103: /* estimate numerical range */
104: if (ctx->estimrange || ctx->lmin == PETSC_MIN_REAL || ctx->lmax == PETSC_MAX_REAL) {
105: PetscCall(MatCreateVecs(ctx->A,&v0,NULL));
106: if (!eps->V) PetscCall(EPSGetBV(eps,&eps->V));
107: PetscCall(BVGetRandomContext(eps->V,&rnd));
108: PetscCall(VecSetRandom(v0,rnd));
109: PetscCall(VecGetArray(v0,&vinit));
110: PetscCallEVSL(LanTrbounds,50,200,eps->tol,vinit,1,&ctx->lmin,&ctx->lmax,NULL);
111: PetscCall(VecRestoreArray(v0,&vinit));
112: PetscCall(VecDestroy(&v0));
113: ctx->estimrange = PETSC_TRUE; /* estimate if called again with another matrix */
114: }
115: PetscCheck(ctx->lmin<=eps->inta && ctx->lmax>=eps->intb,PetscObjectComm((PetscObject)eps),PETSC_ERR_SUP,"The requested interval [%g,%g] must be contained in the numerical range [%g,%g]",(double)eps->inta,(double)eps->intb,(double)ctx->lmin,(double)ctx->lmax);
116: xintv[0] = eps->inta;
117: xintv[1] = eps->intb;
118: xintv[2] = ctx->lmin;
119: xintv[3] = ctx->lmax;
121: /* estimate number of eigenvalues in the interval */
122: switch (ctx->dos) {
123: case EPS_EVSL_DOS_KPM:
124: PetscCall(PetscMalloc1(ctx->deg+1,&mu));
125: if (!rank) PetscCallEVSL(kpmdos,ctx->deg,(int)ctx->damping,ctx->nvec,xintv,mu,&ecount);
126: PetscCallMPI(MPI_Bcast(mu,ctx->deg+1,MPIU_REAL,0,PetscObjectComm((PetscObject)eps)));
127: break;
128: case EPS_EVSL_DOS_LANCZOS:
129: PetscCall(PetscMalloc2(ctx->npoints,&xdos,ctx->npoints,&ydos));
130: if (!rank) PetscCallEVSL(LanDos,ctx->nvec,PetscMin(ctx->steps,eps->n/2),ctx->npoints,xdos,ydos,&ecount,xintv);
131: PetscCallMPI(MPI_Bcast(xdos,ctx->npoints,MPIU_REAL,0,PetscObjectComm((PetscObject)eps)));
132: PetscCallMPI(MPI_Bcast(ydos,ctx->npoints,MPIU_REAL,0,PetscObjectComm((PetscObject)eps)));
133: break;
134: default:
135: SETERRQ(PetscObjectComm((PetscObject)eps),PETSC_ERR_ARG_OUTOFRANGE,"Invalid DOS method");
136: }
137: PetscCallMPI(MPI_Bcast(&ecount,1,MPIU_REAL,0,PetscObjectComm((PetscObject)eps)));
139: PetscCall(PetscInfo(eps,"Estimated eigenvalue count in the interval: %g\n",ecount));
140: eps->ncv = (PetscInt)PetscCeilReal(1.5*ecount);
142: /* slice the spectrum */
143: PetscCall(PetscFree(ctx->sli));
144: PetscCall(PetscMalloc1(ctx->nslices+1,&ctx->sli));
145: if (ctx->dos == EPS_EVSL_DOS_KPM) {
146: PetscCallEVSL(spslicer,ctx->sli,mu,ctx->deg,xintv,ctx->nslices,10*(PetscInt)ecount);
147: PetscCall(PetscFree(mu));
148: } else if (ctx->dos == EPS_EVSL_DOS_LANCZOS) {
149: spslicer2(xdos,ydos,ctx->nslices,ctx->npoints,ctx->sli);
150: PetscCall(PetscFree2(xdos,ydos));
151: }
153: /* approximate number of eigenvalues wanted in each slice */
154: ctx->nev = (PetscInt)(1.0 + ecount/(PetscReal)ctx->nslices) + 2;
156: if (eps->mpd!=PETSC_DEFAULT) PetscCall(PetscInfo(eps,"Warning: parameter mpd ignored\n"));
157: if (eps->max_it==PETSC_DEFAULT) eps->max_it = 1;
158: PetscCall(EPSAllocateSolution(eps,0));
159: PetscFunctionReturn(PETSC_SUCCESS);
160: }
162: static PetscErrorCode EPSSolve_EVSL(EPS eps)
163: {
164: EPS_EVSL *ctx = (EPS_EVSL*)eps->data;
165: PetscInt i,j,k=0,sl,mlan,nevout,*ind,nevmax,rstart,rend,*nevloc,*disp,N;
166: PetscReal *res,xintv[4],*errest;
167: PetscScalar *lam,*X,*Y,*vinit,*eigr;
168: PetscMPIInt size,rank;
169: PetscRandom rnd;
170: Vec v,w,v0,x;
171: VecScatter vs;
172: IS is;
173: polparams pol;
175: PetscFunctionBegin;
176: PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)eps),&size));
177: PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)eps),&rank));
178: PetscCall(PetscLayoutGetRange(ctx->map,&rstart,&rend));
179: nevmax = (rend-rstart)*ctx->nev;
180: PetscCall(MatCreateVecs(ctx->A,&v0,NULL));
181: PetscCall(BVGetRandomContext(eps->V,&rnd));
182: PetscCall(VecSetRandom(v0,rnd));
183: PetscCall(VecGetArray(v0,&vinit));
184: PetscCall(PetscMalloc5(size,&nevloc,size+1,&disp,nevmax,&eigr,nevmax,&errest,nevmax*eps->n,&X));
185: mlan = PetscMin(PetscMax(5*ctx->nev,300),eps->n);
186: for (sl=rstart; sl<rend; sl++) {
187: xintv[0] = ctx->sli[sl];
188: xintv[1] = ctx->sli[sl+1];
189: xintv[2] = ctx->lmin;
190: xintv[3] = ctx->lmax;
191: PetscCall(PetscInfo(ctx->A,"Subinterval %" PetscInt_FMT ": [%.4e, %.4e]\n",sl+1,xintv[0],xintv[1]));
192: set_pol_def(&pol);
193: pol.max_deg = ctx->max_deg;
194: pol.damping = (int)ctx->damping;
195: pol.thresh_int = ctx->thresh;
196: find_pol(xintv,&pol);
197: PetscCall(PetscInfo(ctx->A,"Polynomial [type = %" PetscInt_FMT "], deg %" PetscInt_FMT ", bar %e gam %e\n",pol.type,pol.deg,pol.bar,pol.gam));
198: PetscCallEVSL(ChebLanNr,xintv,mlan,eps->tol,vinit,&pol,&nevout,&lam,&Y,&res,NULL);
199: PetscCheck(k+nevout<=nevmax,PetscObjectComm((PetscObject)eps),PETSC_ERR_LIB,"Too low estimation of eigenvalue count, try modifying the sampling parameters");
200: free_pol(&pol);
201: PetscCall(PetscInfo(ctx->A,"Computed %" PetscInt_FMT " eigenvalues\n",nevout));
202: PetscCall(PetscMalloc1(nevout,&ind));
203: sort_double(nevout,lam,ind);
204: for (i=0;i<nevout;i++) {
205: eigr[i+k] = lam[i];
206: errest[i+k] = res[ind[i]];
207: PetscCall(PetscArraycpy(X+(i+k)*eps->n,Y+ind[i]*eps->n,eps->n));
208: }
209: k += nevout;
210: if (lam) evsl_Free(lam);
211: if (Y) evsl_Free_device(Y);
212: if (res) evsl_Free(res);
213: PetscCall(PetscFree(ind));
214: }
215: PetscCall(VecRestoreArray(v0,&vinit));
216: PetscCall(VecDestroy(&v0));
218: /* gather eigenvalues computed by each MPI process */
219: PetscCallMPI(MPI_Allgather(&k,1,MPIU_INT,nevloc,1,MPIU_INT,PetscObjectComm((PetscObject)eps)));
220: eps->nev = nevloc[0];
221: disp[0] = 0;
222: for (i=1;i<size;i++) {
223: eps->nev += nevloc[i];
224: disp[i] = disp[i-1]+nevloc[i-1];
225: }
226: disp[size] = disp[size-1]+nevloc[size-1];
227: PetscCheck(eps->nev<=eps->ncv,PetscObjectComm((PetscObject)eps),PETSC_ERR_LIB,"Too low estimation of eigenvalue count, try modifying the sampling parameters");
228: PetscCallMPI(MPI_Allgatherv(eigr,k,MPIU_SCALAR,eps->eigr,nevloc,disp,MPIU_SCALAR,PetscObjectComm((PetscObject)eps)));
229: PetscCallMPI(MPI_Allgatherv(errest,k,MPIU_REAL,eps->errest,nevloc,disp,MPIU_REAL,PetscObjectComm((PetscObject)eps)));
230: eps->nconv = eps->nev;
231: eps->its = 1;
232: eps->reason = EPS_CONVERGED_TOL;
234: /* scatter computed eigenvectors and store them in eps->V */
235: PetscCall(BVCreateVec(eps->V,&w));
236: for (i=0;i<size;i++) {
237: N = (rank==i)? eps->n: 0;
238: PetscCall(VecCreateSeq(PETSC_COMM_SELF,N,&x));
239: PetscCall(VecSetFromOptions(x));
240: PetscCall(ISCreateStride(PETSC_COMM_SELF,N,0,1,&is));
241: PetscCall(VecScatterCreate(x,is,w,is,&vs));
242: PetscCall(ISDestroy(&is));
243: for (j=disp[i];j<disp[i+1];j++) {
244: PetscCall(BVGetColumn(eps->V,j,&v));
245: if (rank==i) PetscCall(VecPlaceArray(x,X+(j-disp[i])*eps->n));
246: PetscCall(VecScatterBegin(vs,x,v,INSERT_VALUES,SCATTER_FORWARD));
247: PetscCall(VecScatterEnd(vs,x,v,INSERT_VALUES,SCATTER_FORWARD));
248: if (rank==i) PetscCall(VecResetArray(x));
249: PetscCall(BVRestoreColumn(eps->V,j,&v));
250: }
251: PetscCall(VecScatterDestroy(&vs));
252: PetscCall(VecDestroy(&x));
253: }
254: PetscCall(VecDestroy(&w));
255: PetscCall(PetscFree5(nevloc,disp,eigr,errest,X));
256: PetscFunctionReturn(PETSC_SUCCESS);
257: }
259: static PetscErrorCode EPSEVSLSetSlices_EVSL(EPS eps,PetscInt nslices)
260: {
261: EPS_EVSL *ctx = (EPS_EVSL*)eps->data;
263: PetscFunctionBegin;
264: if (nslices == PETSC_DECIDE || nslices == PETSC_DEFAULT) nslices = 0;
265: else PetscCheck(nslices>0,PetscObjectComm((PetscObject)eps),PETSC_ERR_ARG_OUTOFRANGE,"Number of slices must be 1 at least");
266: if (ctx->nslices != nslices) {
267: ctx->nslices = nslices;
268: eps->state = EPS_STATE_INITIAL;
269: }
270: PetscFunctionReturn(PETSC_SUCCESS);
271: }
273: /*@
274: EPSEVSLSetSlices - Set the number of slices in which the interval must be
275: subdivided.
277: Logically Collective
279: Input Parameters:
280: + eps - the eigensolver context
281: - nslices - the number of slices
283: Options Database Key:
284: . -eps_evsl_slices <n> - set the number of slices to n
286: Notes:
287: By default, one slice per MPI process is used. Depending on the number of
288: eigenvalues, using more slices may be beneficial, but very narrow subintervals
289: imply higher polynomial degree.
291: Level: intermediate
293: .seealso: EPSEVSLGetSlices()
294: @*/
295: PetscErrorCode EPSEVSLSetSlices(EPS eps,PetscInt nslices)
296: {
297: PetscFunctionBegin;
300: PetscTryMethod(eps,"EPSEVSLSetSlices_C",(EPS,PetscInt),(eps,nslices));
301: PetscFunctionReturn(PETSC_SUCCESS);
302: }
304: static PetscErrorCode EPSEVSLGetSlices_EVSL(EPS eps,PetscInt *nslices)
305: {
306: EPS_EVSL *ctx = (EPS_EVSL*)eps->data;
308: PetscFunctionBegin;
309: *nslices = ctx->nslices;
310: PetscFunctionReturn(PETSC_SUCCESS);
311: }
313: /*@
314: EPSEVSLGetSlices - Gets the number of slices in which the interval must be
315: subdivided.
317: Not Collective
319: Input Parameter:
320: . eps - the eigensolver context
322: Output Parameter:
323: . nslices - the number of slices
325: Level: intermediate
327: .seealso: EPSEVSLSetSlices()
328: @*/
329: PetscErrorCode EPSEVSLGetSlices(EPS eps,PetscInt *nslices)
330: {
331: PetscFunctionBegin;
333: PetscAssertPointer(nslices,2);
334: PetscUseMethod(eps,"EPSEVSLGetSlices_C",(EPS,PetscInt*),(eps,nslices));
335: PetscFunctionReturn(PETSC_SUCCESS);
336: }
338: static PetscErrorCode EPSEVSLSetRange_EVSL(EPS eps,PetscReal lmin,PetscReal lmax)
339: {
340: EPS_EVSL *ctx = (EPS_EVSL*)eps->data;
342: PetscFunctionBegin;
343: PetscCheck(lmin<lmax,PetscObjectComm((PetscObject)eps),PETSC_ERR_ARG_WRONG,"Badly defined interval, must be lmin<lmax");
344: if (ctx->lmin != lmin || ctx->lmax != lmax) {
345: ctx->lmin = lmin;
346: ctx->lmax = lmax;
347: eps->state = EPS_STATE_INITIAL;
348: }
349: PetscFunctionReturn(PETSC_SUCCESS);
350: }
352: /*@
353: EPSEVSLSetRange - Defines the numerical range (or field of values) of the problem,
354: that is, the interval containing all eigenvalues.
356: Logically Collective
358: Input Parameters:
359: + eps - the eigensolver context
360: . lmin - left end of the interval
361: - lmax - right end of the interval
363: Options Database Key:
364: . -eps_evsl_range <a,b> - set [a,b] as the numerical range
366: Notes:
367: The filter will be most effective if the numerical range is tight, that is, lmin
368: and lmax are good approximations to the leftmost and rightmost eigenvalues,
369: respectively. If not set by the user, an approximation is computed internally.
371: The wanted computational interval specified via EPSSetInterval() must be
372: contained in the numerical range.
374: Level: intermediate
376: .seealso: EPSEVSLGetRange(), EPSSetInterval()
377: @*/
378: PetscErrorCode EPSEVSLSetRange(EPS eps,PetscReal lmin,PetscReal lmax)
379: {
380: PetscFunctionBegin;
384: PetscTryMethod(eps,"EPSEVSLSetRange_C",(EPS,PetscReal,PetscReal),(eps,lmin,lmax));
385: PetscFunctionReturn(PETSC_SUCCESS);
386: }
388: static PetscErrorCode EPSEVSLGetRange_EVSL(EPS eps,PetscReal *lmin,PetscReal *lmax)
389: {
390: EPS_EVSL *ctx = (EPS_EVSL*)eps->data;
392: PetscFunctionBegin;
393: if (lmin) *lmin = ctx->lmin;
394: if (lmax) *lmax = ctx->lmax;
395: PetscFunctionReturn(PETSC_SUCCESS);
396: }
398: /*@
399: EPSEVSLGetRange - Gets the interval containing all eigenvalues.
401: Not Collective
403: Input Parameter:
404: . eps - the eigensolver context
406: Output Parameters:
407: + lmin - left end of the interval
408: - lmax - right end of the interval
410: Level: intermediate
412: .seealso: EPSEVSLSetRange()
413: @*/
414: PetscErrorCode EPSEVSLGetRange(EPS eps,PetscReal *lmin,PetscReal *lmax)
415: {
416: PetscFunctionBegin;
418: PetscUseMethod(eps,"EPSEVSLGetRange_C",(EPS,PetscReal*,PetscReal*),(eps,lmin,lmax));
419: PetscFunctionReturn(PETSC_SUCCESS);
420: }
422: static PetscErrorCode EPSEVSLSetDOSParameters_EVSL(EPS eps,EPSEVSLDOSMethod dos,PetscInt nvec,PetscInt deg,PetscInt steps,PetscInt npoints)
423: {
424: EPS_EVSL *ctx = (EPS_EVSL*)eps->data;
426: PetscFunctionBegin;
427: ctx->dos = dos;
428: if (nvec == PETSC_DECIDE || nvec == PETSC_DEFAULT) ctx->nvec = 80;
429: else {
430: PetscCheck(nvec>0,PetscObjectComm((PetscObject)eps),PETSC_ERR_ARG_OUTOFRANGE,"The nvec argument must be > 0");
431: ctx->nvec = nvec;
432: }
433: switch (dos) {
434: case EPS_EVSL_DOS_KPM:
435: if (deg == PETSC_DECIDE || deg == PETSC_DEFAULT) ctx->deg = 300;
436: else {
437: PetscCheck(deg>0,PetscObjectComm((PetscObject)eps),PETSC_ERR_ARG_OUTOFRANGE,"The deg argument must be > 0");
438: ctx->deg = deg;
439: }
440: break;
441: case EPS_EVSL_DOS_LANCZOS:
442: if (steps == PETSC_DECIDE || steps == PETSC_DEFAULT) ctx->steps = 40;
443: else {
444: PetscCheck(steps>0,PetscObjectComm((PetscObject)eps),PETSC_ERR_ARG_OUTOFRANGE,"The steps argument must be > 0");
445: ctx->steps = steps;
446: }
447: if (npoints == PETSC_DECIDE || npoints == PETSC_DEFAULT) ctx->npoints = 200;
448: else {
449: PetscCheck(npoints>0,PetscObjectComm((PetscObject)eps),PETSC_ERR_ARG_OUTOFRANGE,"The npoints argument must be > 0");
450: ctx->npoints = npoints;
451: }
452: break;
453: }
454: eps->state = EPS_STATE_INITIAL;
455: PetscFunctionReturn(PETSC_SUCCESS);
456: }
458: /*@
459: EPSEVSLSetDOSParameters - Defines the parameters used for computing the
460: density of states (DOS) in the EVSL solver.
462: Logically Collective
464: Input Parameters:
465: + eps - the eigensolver context
466: . dos - DOS method, either KPM or Lanczos
467: . nvec - number of sample vectors
468: . deg - polynomial degree (KPM only)
469: . steps - number of Lanczos steps (Lanczos only)
470: - npoints - number of sample points (Lanczos only)
472: Options Database Keys:
473: + -eps_evsl_dos_method <dos> - set the DOS method, either kpm or lanczos
474: . -eps_evsl_dos_nvec <n> - set the number of sample vectors
475: . -eps_evsl_dos_degree <n> - set the polynomial degree
476: . -eps_evsl_dos_steps <n> - set the number of Lanczos steps
477: - -eps_evsl_dos_npoints <n> - set the number of sample points
479: Notes:
480: The density of states (or spectral density) can be approximated with two
481: methods, kernel polynomial method (KPM) or Lanczos. Some parameters for
482: these methods can be set by the user with this function, with some of
483: them being relevant for one of the methods only.
485: Level: intermediate
487: .seealso: EPSEVSLGetDOSParameters()
488: @*/
489: PetscErrorCode EPSEVSLSetDOSParameters(EPS eps,EPSEVSLDOSMethod dos,PetscInt nvec,PetscInt deg,PetscInt steps,PetscInt npoints)
490: {
491: PetscFunctionBegin;
498: PetscTryMethod(eps,"EPSEVSLSetDOSParameters_C",(EPS,EPSEVSLDOSMethod,PetscInt,PetscInt,PetscInt,PetscInt),(eps,dos,nvec,deg,steps,npoints));
499: PetscFunctionReturn(PETSC_SUCCESS);
500: }
502: static PetscErrorCode EPSEVSLGetDOSParameters_EVSL(EPS eps,EPSEVSLDOSMethod *dos,PetscInt *nvec,PetscInt *deg,PetscInt *steps,PetscInt *npoints)
503: {
504: EPS_EVSL *ctx = (EPS_EVSL*)eps->data;
506: PetscFunctionBegin;
507: if (dos) *dos = ctx->dos;
508: if (nvec) *nvec = ctx->nvec;
509: if (deg) *deg = ctx->deg;
510: if (steps) *steps = ctx->steps;
511: if (npoints) *npoints = ctx->npoints;
512: PetscFunctionReturn(PETSC_SUCCESS);
513: }
515: /*@
516: EPSEVSLGetDOSParameters - Gets the parameters used for computing the
517: density of states (DOS) in the EVSL solver.
519: Not Collective
521: Input Parameter:
522: . eps - the eigensolver context
524: Output Parameters:
525: + dos - DOS method, either KPM or Lanczos
526: . nvec - number of sample vectors
527: . deg - polynomial degree (KPM only)
528: . steps - number of Lanczos steps (Lanczos only)
529: - npoints - number of sample points (Lanczos only)
531: Level: intermediate
533: .seealso: EPSEVSLSetDOSParameters()
534: @*/
535: PetscErrorCode EPSEVSLGetDOSParameters(EPS eps,EPSEVSLDOSMethod *dos,PetscInt *nvec,PetscInt *deg,PetscInt *steps,PetscInt *npoints)
536: {
537: PetscFunctionBegin;
539: PetscUseMethod(eps,"EPSEVSLGetDOSParameters_C",(EPS,EPSEVSLDOSMethod*,PetscInt*,PetscInt*,PetscInt*,PetscInt*),(eps,dos,nvec,deg,steps,npoints));
540: PetscFunctionReturn(PETSC_SUCCESS);
541: }
543: static PetscErrorCode EPSEVSLSetPolParameters_EVSL(EPS eps,PetscInt max_deg,PetscReal thresh)
544: {
545: EPS_EVSL *ctx = (EPS_EVSL*)eps->data;
547: PetscFunctionBegin;
548: if (max_deg == PETSC_DECIDE || max_deg == PETSC_DEFAULT) ctx->max_deg = 10000;
549: else {
550: PetscCheck(max_deg>2,PetscObjectComm((PetscObject)eps),PETSC_ERR_ARG_OUTOFRANGE,"The max_deg argument must be > 2");
551: ctx->max_deg = max_deg;
552: }
553: if (thresh == (PetscReal)PETSC_DECIDE || thresh == (PetscReal)PETSC_DEFAULT) ctx->thresh = 0.8;
554: else {
555: PetscCheck(thresh>0.0,PetscObjectComm((PetscObject)eps),PETSC_ERR_ARG_OUTOFRANGE,"The thresh argument must be > 0.0");
556: ctx->thresh = thresh;
557: }
558: eps->state = EPS_STATE_INITIAL;
559: PetscFunctionReturn(PETSC_SUCCESS);
560: }
562: /*@
563: EPSEVSLSetPolParameters - Defines the parameters used for building the
564: building the polynomial in the EVSL solver.
566: Logically Collective
568: Input Parameters:
569: + eps - the eigensolver context
570: . max_deg - maximum degree allowed for the polynomial
571: - thresh - threshold for accepting polynomial
573: Options Database Keys:
574: + -eps_evsl_pol_max_deg <d> - set maximum polynomial degree
575: - -eps_evsl_pol_thresh <t> - set the threshold
577: Level: intermediate
579: .seealso: EPSEVSLGetPolParameters()
580: @*/
581: PetscErrorCode EPSEVSLSetPolParameters(EPS eps,PetscInt max_deg,PetscReal thresh)
582: {
583: PetscFunctionBegin;
587: PetscTryMethod(eps,"EPSEVSLSetPolParameters_C",(EPS,PetscInt,PetscReal),(eps,max_deg,thresh));
588: PetscFunctionReturn(PETSC_SUCCESS);
589: }
591: static PetscErrorCode EPSEVSLGetPolParameters_EVSL(EPS eps,PetscInt *max_deg,PetscReal *thresh)
592: {
593: EPS_EVSL *ctx = (EPS_EVSL*)eps->data;
595: PetscFunctionBegin;
596: if (max_deg) *max_deg = ctx->max_deg;
597: if (thresh) *thresh = ctx->thresh;
598: PetscFunctionReturn(PETSC_SUCCESS);
599: }
601: /*@
602: EPSEVSLGetPolParameters - Gets the parameters used for building the
603: polynomial in the EVSL solver.
605: Not Collective
607: Input Parameter:
608: . eps - the eigensolver context
610: Output Parameters:
611: + max_deg - the maximum degree of the polynomial
612: - thresh - the threshold
614: Level: intermediate
616: .seealso: EPSEVSLSetPolParameters()
617: @*/
618: PetscErrorCode EPSEVSLGetPolParameters(EPS eps,PetscInt *max_deg,PetscReal *thresh)
619: {
620: PetscFunctionBegin;
622: PetscUseMethod(eps,"EPSEVSLGetPolParameters_C",(EPS,PetscInt*,PetscReal*),(eps,max_deg,thresh));
623: PetscFunctionReturn(PETSC_SUCCESS);
624: }
626: static PetscErrorCode EPSEVSLSetDamping_EVSL(EPS eps,EPSEVSLDamping damping)
627: {
628: EPS_EVSL *ctx = (EPS_EVSL*)eps->data;
630: PetscFunctionBegin;
631: if (ctx->damping != damping) {
632: ctx->damping = damping;
633: eps->state = EPS_STATE_INITIAL;
634: }
635: PetscFunctionReturn(PETSC_SUCCESS);
636: }
638: /*@
639: EPSEVSLSetDamping - Set the type of damping to be used in EVSL.
641: Logically Collective
643: Input Parameters:
644: + eps - the eigensolver context
645: - damping - the type of damping
647: Options Database Key:
648: . -eps_evsl_damping <n> - set the type of damping
650: Notes:
651: Damping is applied when building the polynomial to be used when solving the
652: eigenproblem, and also during estimation of DOS with the KPM method.
654: Level: intermediate
656: .seealso: EPSEVSLGetDamping(), EPSEVSLSetDOSParameters()
657: @*/
658: PetscErrorCode EPSEVSLSetDamping(EPS eps,EPSEVSLDamping damping)
659: {
660: PetscFunctionBegin;
663: PetscTryMethod(eps,"EPSEVSLSetDamping_C",(EPS,EPSEVSLDamping),(eps,damping));
664: PetscFunctionReturn(PETSC_SUCCESS);
665: }
667: static PetscErrorCode EPSEVSLGetDamping_EVSL(EPS eps,EPSEVSLDamping *damping)
668: {
669: EPS_EVSL *ctx = (EPS_EVSL*)eps->data;
671: PetscFunctionBegin;
672: *damping = ctx->damping;
673: PetscFunctionReturn(PETSC_SUCCESS);
674: }
676: /*@
677: EPSEVSLGetDamping - Gets the type of damping.
679: Not Collective
681: Input Parameter:
682: . eps - the eigensolver context
684: Output Parameter:
685: . damping - the type of damping
687: Level: intermediate
689: .seealso: EPSEVSLSetDamping()
690: @*/
691: PetscErrorCode EPSEVSLGetDamping(EPS eps,EPSEVSLDamping *damping)
692: {
693: PetscFunctionBegin;
695: PetscAssertPointer(damping,2);
696: PetscUseMethod(eps,"EPSEVSLGetDamping_C",(EPS,EPSEVSLDamping*),(eps,damping));
697: PetscFunctionReturn(PETSC_SUCCESS);
698: }
700: static PetscErrorCode EPSView_EVSL(EPS eps,PetscViewer viewer)
701: {
702: PetscBool isascii;
703: EPS_EVSL *ctx = (EPS_EVSL*)eps->data;
705: PetscFunctionBegin;
706: PetscCall(PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&isascii));
707: if (isascii) {
708: PetscCall(PetscViewerASCIIPrintf(viewer," numerical range = [%g,%g]\n",(double)ctx->lmin,(double)ctx->lmax));
709: PetscCall(PetscViewerASCIIPrintf(viewer," number of slices = %" PetscInt_FMT "\n",ctx->nslices));
710: PetscCall(PetscViewerASCIIPrintf(viewer," type of damping = %s\n",EPSEVSLDampings[ctx->damping]));
711: PetscCall(PetscViewerASCIIPrintf(viewer," computing DOS with %s: nvec=%" PetscInt_FMT ", ",EPSEVSLDOSMethods[ctx->dos],ctx->nvec));
712: PetscCall(PetscViewerASCIIUseTabs(viewer,PETSC_FALSE));
713: switch (ctx->dos) {
714: case EPS_EVSL_DOS_KPM:
715: PetscCall(PetscViewerASCIIPrintf(viewer,"degree=%" PetscInt_FMT "\n",ctx->deg));
716: break;
717: case EPS_EVSL_DOS_LANCZOS:
718: PetscCall(PetscViewerASCIIPrintf(viewer,"steps=%" PetscInt_FMT ", npoints=%" PetscInt_FMT "\n",ctx->steps,ctx->npoints));
719: break;
720: }
721: PetscCall(PetscViewerASCIIUseTabs(viewer,PETSC_TRUE));
722: PetscCall(PetscViewerASCIIPrintf(viewer," polynomial parameters: max degree = %" PetscInt_FMT ", threshold = %g\n",ctx->max_deg,(double)ctx->thresh));
723: }
724: PetscFunctionReturn(PETSC_SUCCESS);
725: }
727: static PetscErrorCode EPSSetFromOptions_EVSL(EPS eps,PetscOptionItems *PetscOptionsObject)
728: {
729: PetscReal array[2]={0,0},th;
730: PetscInt k,i1,i2,i3,i4;
731: PetscBool flg,flg1;
732: EPSEVSLDOSMethod dos;
733: EPSEVSLDamping damping;
734: EPS_EVSL *ctx = (EPS_EVSL*)eps->data;
736: PetscFunctionBegin;
737: PetscOptionsHeadBegin(PetscOptionsObject,"EPS EVSL Options");
739: k = 2;
740: PetscCall(PetscOptionsRealArray("-eps_evsl_range","Interval containing all eigenvalues (two real values separated with a comma without spaces)","EPSEVSLSetRange",array,&k,&flg));
741: if (flg) {
742: PetscCheck(k>1,PetscObjectComm((PetscObject)eps),PETSC_ERR_ARG_SIZ,"Must pass two values in -eps_evsl_range (comma-separated without spaces)");
743: PetscCall(EPSEVSLSetRange(eps,array[0],array[1]));
744: }
746: PetscCall(PetscOptionsInt("-eps_evsl_slices","Number of slices","EPSEVSLSetSlices",ctx->nslices,&i1,&flg));
747: if (flg) PetscCall(EPSEVSLSetSlices(eps,i1));
749: PetscCall(PetscOptionsEnum("-eps_evsl_damping","Type of damping","EPSEVSLSetDamping",EPSEVSLDampings,(PetscEnum)ctx->damping,(PetscEnum*)&damping,&flg));
750: if (flg) PetscCall(EPSEVSLSetDamping(eps,damping));
752: PetscCall(EPSEVSLGetDOSParameters(eps,&dos,&i1,&i2,&i3,&i4));
753: PetscCall(PetscOptionsEnum("-eps_evsl_dos_method","Method to compute the DOS","EPSEVSLSetDOSParameters",EPSEVSLDOSMethods,(PetscEnum)ctx->dos,(PetscEnum*)&dos,&flg));
754: PetscCall(PetscOptionsInt("-eps_evsl_dos_nvec","Number of sample vectors for DOS","EPSEVSLSetDOSParameters",i1,&i1,&flg1));
755: if (flg1) flg = PETSC_TRUE;
756: PetscCall(PetscOptionsInt("-eps_evsl_dos_degree","Polynomial degree used for DOS","EPSEVSLSetDOSParameters",i2,&i2,&flg1));
757: if (flg1) flg = PETSC_TRUE;
758: PetscCall(PetscOptionsInt("-eps_evsl_dos_steps","Number of Lanczos steps in DOS","EPSEVSLSetDOSParameters",i3,&i3,&flg1));
759: if (flg1) flg = PETSC_TRUE;
760: PetscCall(PetscOptionsInt("-eps_evsl_dos_npoints","Number of sample points used for DOS","EPSEVSLSetDOSParameters",i4,&i4,&flg1));
761: if (flg || flg1) PetscCall(EPSEVSLSetDOSParameters(eps,dos,i1,i2,i3,i4));
763: PetscCall(EPSEVSLGetPolParameters(eps,&i1,&th));
764: PetscCall(PetscOptionsInt("-eps_evsl_pol_max_deg","Maximum degree allowed for the polynomial","EPSEVSLSetPolParameters",i1,&i1,&flg));
765: PetscCall(PetscOptionsReal("-eps_evsl_pol_threshold","Threshold for accepting polynomial","EPSEVSLSetPolParameters",th,&th,&flg1));
766: if (flg || flg1) PetscCall(EPSEVSLSetPolParameters(eps,i1,th));
768: PetscOptionsHeadEnd();
769: PetscFunctionReturn(PETSC_SUCCESS);
770: }
772: static PetscErrorCode EPSDestroy_EVSL(EPS eps)
773: {
774: EPS_EVSL *ctx = (EPS_EVSL*)eps->data;
776: PetscFunctionBegin;
777: if (ctx->initialized) EVSLFinish();
778: PetscCall(PetscLayoutDestroy(&ctx->map));
779: PetscCall(PetscFree(ctx->sli));
780: PetscCall(PetscFree(eps->data));
781: PetscCall(PetscObjectComposeFunction((PetscObject)eps,"EPSEVSLSetRange_C",NULL));
782: PetscCall(PetscObjectComposeFunction((PetscObject)eps,"EPSEVSLGetRange_C",NULL));
783: PetscCall(PetscObjectComposeFunction((PetscObject)eps,"EPSEVSLSetSlices_C",NULL));
784: PetscCall(PetscObjectComposeFunction((PetscObject)eps,"EPSEVSLGetSlices_C",NULL));
785: PetscCall(PetscObjectComposeFunction((PetscObject)eps,"EPSEVSLSetDOSParameters_C",NULL));
786: PetscCall(PetscObjectComposeFunction((PetscObject)eps,"EPSEVSLGetDOSParameters_C",NULL));
787: PetscCall(PetscObjectComposeFunction((PetscObject)eps,"EPSEVSLSetPolParameters_C",NULL));
788: PetscCall(PetscObjectComposeFunction((PetscObject)eps,"EPSEVSLGetPolParameters_C",NULL));
789: PetscCall(PetscObjectComposeFunction((PetscObject)eps,"EPSEVSLSetDamping_C",NULL));
790: PetscCall(PetscObjectComposeFunction((PetscObject)eps,"EPSEVSLGetDamping_C",NULL));
791: PetscFunctionReturn(PETSC_SUCCESS);
792: }
794: static PetscErrorCode EPSReset_EVSL(EPS eps)
795: {
796: EPS_EVSL *ctx = (EPS_EVSL*)eps->data;
798: PetscFunctionBegin;
799: PetscCall(MatDestroy(&ctx->A));
800: PetscCall(VecDestroy(&ctx->x));
801: PetscCall(VecDestroy(&ctx->y));
802: PetscFunctionReturn(PETSC_SUCCESS);
803: }
805: SLEPC_EXTERN PetscErrorCode EPSCreate_EVSL(EPS eps)
806: {
807: EPS_EVSL *ctx;
809: PetscFunctionBegin;
810: PetscCall(PetscNew(&ctx));
811: eps->data = (void*)ctx;
813: ctx->nslices = 0;
814: ctx->lmin = PETSC_MIN_REAL;
815: ctx->lmax = PETSC_MAX_REAL;
816: ctx->dos = EPS_EVSL_DOS_KPM;
817: ctx->nvec = 80;
818: ctx->deg = 300;
819: ctx->steps = 40;
820: ctx->npoints = 200;
821: ctx->max_deg = 10000;
822: ctx->thresh = 0.8;
823: ctx->damping = EPS_EVSL_DAMPING_SIGMA;
825: eps->categ = EPS_CATEGORY_OTHER;
827: eps->ops->solve = EPSSolve_EVSL;
828: eps->ops->setup = EPSSetUp_EVSL;
829: eps->ops->setupsort = EPSSetUpSort_Basic;
830: eps->ops->setfromoptions = EPSSetFromOptions_EVSL;
831: eps->ops->destroy = EPSDestroy_EVSL;
832: eps->ops->reset = EPSReset_EVSL;
833: eps->ops->view = EPSView_EVSL;
834: eps->ops->backtransform = EPSBackTransform_Default;
835: eps->ops->setdefaultst = EPSSetDefaultST_NoFactor;
837: PetscCall(PetscObjectComposeFunction((PetscObject)eps,"EPSEVSLSetRange_C",EPSEVSLSetRange_EVSL));
838: PetscCall(PetscObjectComposeFunction((PetscObject)eps,"EPSEVSLGetRange_C",EPSEVSLGetRange_EVSL));
839: PetscCall(PetscObjectComposeFunction((PetscObject)eps,"EPSEVSLSetSlices_C",EPSEVSLSetSlices_EVSL));
840: PetscCall(PetscObjectComposeFunction((PetscObject)eps,"EPSEVSLGetSlices_C",EPSEVSLGetSlices_EVSL));
841: PetscCall(PetscObjectComposeFunction((PetscObject)eps,"EPSEVSLSetDOSParameters_C",EPSEVSLSetDOSParameters_EVSL));
842: PetscCall(PetscObjectComposeFunction((PetscObject)eps,"EPSEVSLGetDOSParameters_C",EPSEVSLGetDOSParameters_EVSL));
843: PetscCall(PetscObjectComposeFunction((PetscObject)eps,"EPSEVSLSetPolParameters_C",EPSEVSLSetPolParameters_EVSL));
844: PetscCall(PetscObjectComposeFunction((PetscObject)eps,"EPSEVSLGetPolParameters_C",EPSEVSLGetPolParameters_EVSL));
845: PetscCall(PetscObjectComposeFunction((PetscObject)eps,"EPSEVSLSetDamping_C",EPSEVSLSetDamping_EVSL));
846: PetscCall(PetscObjectComposeFunction((PetscObject)eps,"EPSEVSLGetDamping_C",EPSEVSLGetDamping_EVSL));
847: PetscFunctionReturn(PETSC_SUCCESS);
848: }