Actual source code: dvd_initv.c
1: /*
2: SLEPc eigensolver: "davidson"
4: Step: init subspace V
6: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
7: SLEPc - Scalable Library for Eigenvalue Problem Computations
8: Copyright (c) 2002-2011, Universitat Politecnica de Valencia, Spain
10: This file is part of SLEPc.
11:
12: SLEPc is free software: you can redistribute it and/or modify it under the
13: terms of version 3 of the GNU Lesser General Public License as published by
14: the Free Software Foundation.
16: SLEPc is distributed in the hope that it will be useful, but WITHOUT ANY
17: WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
18: FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for
19: more details.
21: You should have received a copy of the GNU Lesser General Public License
22: along with SLEPc. If not, see <http://www.gnu.org/licenses/>.
23: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
24: */
26: #include davidson.h
28: PetscErrorCode dvd_initV_classic_0(dvdDashboard *d);
29: PetscErrorCode dvd_initV_krylov_0(dvdDashboard *d);
30: PetscErrorCode dvd_initV_d(dvdDashboard *d);
32: typedef struct {
33: PetscInt k, /* desired initial subspace size */
34: user; /* number of user initial vectors */
35: void *old_initV_data; /* old initV data */
36: } dvdInitV;
40: PetscErrorCode dvd_initV(dvdDashboard *d, dvdBlackboard *b, PetscInt k,
41: PetscInt user, PetscBool krylov)
42: {
43: PetscErrorCode ierr;
44: dvdInitV *data;
48: /* Setting configuration constrains */
49: b->max_size_V = PetscMax(b->max_size_V, k);
50: if (krylov)
51: b->max_size_auxV = PetscMax(b->max_size_auxV, 1);
53: /* Setup the step */
54: if (b->state >= DVD_STATE_CONF) {
55: PetscMalloc(sizeof(dvdInitV), &data);
56: data->k = k;
57: data->user = PetscMin(k, user);
58: data->old_initV_data = d->initV_data;
59: d->initV_data = data;
60: if (krylov) {
61: d->initV = dvd_initV_krylov_0;
62: } else {
63: d->initV = dvd_initV_classic_0;
64: }
65: DVD_FL_ADD(d->destroyList, dvd_initV_d);
66: }
68: return(0);
69: }
74: PetscErrorCode dvd_initV_classic_0(dvdDashboard *d)
75: {
76: PetscErrorCode ierr;
77: dvdInitV *data = (dvdInitV*)d->initV_data;
78: PetscInt i, user = PetscMin(data->user, d->max_size_V),
79: k = PetscMin(data->k, d->max_size_V);
83: /* Generate a set of random initial vectors and orthonormalize them */
84: for (i=user; i<k; i++) {
85: SlepcVecSetRandom(d->V[i], d->eps->rand);
86: }
87: d->V_tra_s = 0; d->V_tra_e = 0;
88: d->V_new_s = 0; d->V_new_e = i;
90: /* After that the user vectors will be destroyed */
91: data->user = 0;
92:
93: return(0);
94: }
98: PetscErrorCode dvd_initV_krylov_0(dvdDashboard *d)
99: {
100: PetscErrorCode ierr;
101: dvdInitV *data = (dvdInitV*)d->initV_data;
102: PetscInt i, user = PetscMin(data->user, d->max_size_V),
103: k = PetscMin(data->k, d->max_size_V);
104: Vec *cX = d->BcX? d->BcX : ( (d->cY && !d->W)? d->cY : d->cX );
108: /* If needed, generate a random vector for starting the arnoldi method */
109: if (user == 0) {
110: SlepcVecSetRandom(d->V[0], d->eps->rand);
111: user = 1;
112: }
114: /* Perform k steps of Arnoldi with the operator K^{-1}*(t[1]*A-t[2]*B) */
115: dvd_orthV(d->ipV, d->eps->DS, d->eps->nds, cX, d->size_cX, d->V, 0,
116: user, d->auxS, d->eps->rand);
117: for (i=user; i<k; i++) {
118: /* aux <- theta[1]A*in - theta[0]*B*in */
119: if (d->B) {
120: MatMult(d->A, d->V[i-user], d->V[i]);
121: MatMult(d->B, d->V[i-user], d->auxV[0]);
122: VecAXPBY(d->auxV[0], d->target[1], -d->target[0], d->V[i]);
123:
124: } else {
125: MatMult(d->A, d->V[i-user], d->auxV[0]);
126: VecAXPBY(d->auxV[0], -d->target[0], d->target[1], d->V[i-user]);
127:
128: }
129: d->improvex_precond(d, 0, d->auxV[0], d->V[i]);
130: dvd_orthV(d->ipV, d->eps->DS, d->eps->nds, cX, d->size_cX, d->V, i,
131: i+1, d->auxS, d->eps->rand);
132: }
134: d->V_tra_s = 0; d->V_tra_e = 0;
135: d->V_new_s = 0; d->V_new_e = i;
137: /* After that the user vectors will be destroyed */
138: data->user = 0;
140: return(0);
141: }
145: PetscErrorCode dvd_initV_d(dvdDashboard *d)
146: {
147: PetscErrorCode ierr;
148: dvdInitV *data = (dvdInitV*)d->initV_data;
152: /* Restore changes in dvdDashboard */
153: d->initV_data = data->old_initV_data;
155: /* Free local data */
156: PetscFree(data);
158: return(0);
159: }