/[escript]/trunk/paso/src/TFQMR.c
ViewVC logotype

Contents of /trunk/paso/src/TFQMR.c

Parent Directory Parent Directory | Revision Log Revision Log


Revision 1703 - (show annotations)
Thu Aug 14 05:34:25 2008 UTC (11 years, 2 months ago) by artak
File MIME type: text/plain
File size: 7482 byte(s)
TFQMR solver is added to PASO solver. It is not parallelised yet.
1
2 /*******************************************************
3 *
4 * Copyright 2003-2007 by ACceSS MNRF
5 * Copyright 2007 by University of Queensland
6 *
7 * http://esscc.uq.edu.au
8 * Primary Business: Queensland, Australia
9 * Licensed under the Open Software License version 3.0
10 * http://www.opensource.org/licenses/osl-3.0.php
11 *
12 *******************************************************/
13
14 /* TFQMR iterations */
15
16 #include "SystemMatrix.h"
17 #include "Paso.h"
18 #include "Solver.h"
19 #include "PasoUtil.h"
20
21 #ifdef _OPENMP
22 #include <omp.h>
23 #endif
24
25 #ifdef PASO_MPI
26 #include <mpi.h>
27 #endif
28
29 /*
30 *
31 * Purpose
32 * =======
33 *
34 * TFQMR solves the linear system A*x = b
35 *
36 * Convergence test: norm( b - A*x )< TOL.
37 * For other measures, see the above reference.
38 *
39 * Arguments
40 * =========
41 *
42 * r (input) DOUBLE PRECISION array, dimension N.
43 * On entry, residual of inital guess x
44 *
45 * x (input/output) DOUBLE PRECISION array, dimension N.
46 * On input, the initial guess.
47 *
48 * ITER (input/output) INT
49 * On input, the maximum iterations to be performed.
50 * On output, actual number of iterations performed.
51 *
52 * INFO (output) INT
53 *
54 * = SOLVER_NO_ERROR: Successful exit. Iterated approximate solution returned.
55 * = SOLVEr_MAXITER_REACHED
56 * = SOLVER_INPUT_ERROR Illegal parameter:
57 * = SOLVEr_BREAKDOWN: If parameters rHO or OMEGA become smaller
58 * = SOLVER_MEMORY_ERROR : If parameters rHO or OMEGA become smaller
59 *
60 * ==============================================================
61 */
62
63 /* #define PASO_DYNAMIC_SCHEDULING_MVM */
64
65 #if defined PASO_DYNAMIC_SCHEDULING_MVM && defined __OPENMP
66 #define USE_DYNAMIC_SCHEDULING
67 #endif
68
69 err_t Paso_Solver_TFQMR(
70 Paso_SystemMatrix * A,
71 double * r,
72 double * x,
73 dim_t *iter,
74 double * tolerance,
75 Paso_Performance* pp) {
76
77 /* Local variables */
78 dim_t num_iter=0,maxit;
79 bool_t breakFlag=FALSE, maxIterFlag=FALSE, convergeFlag=FALSE;
80 err_t status = SOLVER_NO_ERROR;
81 dim_t n = Paso_SystemMatrix_getTotalNumRows(A);
82 double *u1=NULL, *u2=NULL, *y1=NULL, *y2=NULL, *d=NULL, *w=NULL, *v=NULL, *v_old=NULL, *tmp=NULL ;
83
84 double eta,theta,tau,rho,beta,alpha,sigma,rhon,c;
85
86 double norm_of_residual;
87
88 /* */
89 /*-----------------------------------------------------------------*/
90 /* */
91 /* Start of Calculation : */
92 /* --------------------- */
93 /* */
94 /* */
95 u1=TMPMEMALLOC(n,double);
96 u2=TMPMEMALLOC(n,double);
97 y1=TMPMEMALLOC(n,double);
98 y2=TMPMEMALLOC(n,double);
99 d=TMPMEMALLOC(n,double);
100 w=TMPMEMALLOC(n,double);
101 v=TMPMEMALLOC(n,double);
102 v_old=TMPMEMALLOC(n,double);
103
104
105 tmp=TMPMEMALLOC(n,double);
106
107
108 if (u1 ==NULL || u2== NULL || y1 == NULL || y2== NULL || d==NULL || w==NULL || v==NULL || v_old==NULL) {
109 status=SOLVER_MEMORY_ERROR;
110 }
111
112 maxit = *iter;
113
114 /* Test the input parameters. */
115 if (n < 0 || maxit<=0 ) {
116 status=SOLVER_INPUT_ERROR;
117 }
118
119 Performance_startMonitor(pp,PERFORMANCE_PRECONDITIONER);
120 Paso_Solver_solvePreconditioner(A,r,r);
121 Performance_stopMonitor(pp,PERFORMANCE_PRECONDITIONER);
122
123 Performance_startMonitor(pp,PERFORMANCE_SOLVER);
124
125 Paso_zeroes(n,u2);
126 Paso_zeroes(n,y2);
127
128 Paso_Copy(n,w,r);
129 Paso_Copy(n,y1,r);
130
131 Paso_zeroes(n,d);
132
133 Performance_stopMonitor(pp,PERFORMANCE_SOLVER);
134 Performance_startMonitor(pp,PERFORMANCE_MVM);
135 Paso_SystemMatrix_MatrixVector_CSR_OFFSET0(ONE, A, y1,ZERO,v);
136 Performance_stopMonitor(pp,PERFORMANCE_MVM);
137 Performance_startMonitor(pp,PERFORMANCE_SOLVER);
138
139 Performance_stopMonitor(pp,PERFORMANCE_SOLVER);
140 Performance_startMonitor(pp,PERFORMANCE_PRECONDITIONER);
141 Paso_Solver_solvePreconditioner(A,v,v);
142 Performance_stopMonitor(pp,PERFORMANCE_PRECONDITIONER);
143 Performance_startMonitor(pp,PERFORMANCE_SOLVER);
144
145 Paso_Copy(n,u1,v);
146
147 theta = 0.0;
148 eta = 0.0;
149
150 tau = Paso_l2(n,r,A->mpi_info);
151
152 rho = tau * tau;
153 int m=1;
154 int j=0;
155
156 norm_of_residual=tau*sqrt ( m + 1 );
157
158 while (!(convergeFlag || maxIterFlag || breakFlag || (status !=SOLVER_NO_ERROR) ))
159 {
160
161
162 sigma=Paso_InnerProduct(n,r,v,A->mpi_info);
163
164 if (! (breakFlag = (ABS(sigma) == 0.))) {
165
166 alpha = rho / sigma;
167
168 for (j=0; j<=1; j=j+1)
169 {
170 /* Compute y2 and u2 only if you have to */
171 if ( j == 1 ){
172 Paso_LinearCombination(n,y2,1.,y1,-alpha,v);
173
174 Performance_stopMonitor(pp,PERFORMANCE_SOLVER);
175 Performance_startMonitor(pp,PERFORMANCE_MVM);
176 Paso_SystemMatrix_MatrixVector_CSR_OFFSET0(ONE, A, y2,ZERO,u2);
177 Performance_stopMonitor(pp,PERFORMANCE_MVM);
178 Performance_startMonitor(pp,PERFORMANCE_SOLVER);
179
180 Performance_stopMonitor(pp,PERFORMANCE_SOLVER);
181 Performance_startMonitor(pp,PERFORMANCE_PRECONDITIONER);
182 Paso_Solver_solvePreconditioner(A,u2,u2);
183 Performance_stopMonitor(pp,PERFORMANCE_PRECONDITIONER);
184 Performance_startMonitor(pp,PERFORMANCE_SOLVER);
185 }
186 m = 2 * (num_iter+1) - 2 + (j+1);
187 if (j==0) {
188 Paso_Update(n,1.,w,-alpha,u1);
189 Paso_Update(n,( theta * theta * eta / alpha ),d,1.,y1);
190 }
191 if (j==1) {
192 Paso_Update(n,1.,w,-alpha,u2);
193 Paso_Update(n,( theta * theta * eta / alpha ),d,1.,y2);
194 }
195
196 theta =Paso_l2(n,w,A->mpi_info)/tau;
197 c = 1.0 / sqrt ( 1.0 + theta * theta );
198 tau = tau * theta * c;
199 eta = c * c * alpha;
200 Paso_Update(n,1.,x,eta,d);
201 }
202
203 breakFlag = (ABS(rho) == 0);
204
205 rhon = Paso_InnerProduct(n,r,w,A->mpi_info);
206 beta = rhon / rho;
207 rho = rhon;
208
209 Paso_LinearCombination(n,y1,1.,w,beta,y2);
210
211 Performance_stopMonitor(pp,PERFORMANCE_SOLVER);
212 Performance_startMonitor(pp,PERFORMANCE_MVM);
213 Paso_SystemMatrix_MatrixVector_CSR_OFFSET0(ONE, A, y1,ZERO,u1);
214 Performance_stopMonitor(pp,PERFORMANCE_MVM);
215 Performance_startMonitor(pp,PERFORMANCE_SOLVER);
216
217 Performance_stopMonitor(pp,PERFORMANCE_SOLVER);
218 Performance_startMonitor(pp,PERFORMANCE_PRECONDITIONER);
219 Paso_Solver_solvePreconditioner(A,u1,u1);
220 Performance_stopMonitor(pp,PERFORMANCE_PRECONDITIONER);
221 Performance_startMonitor(pp,PERFORMANCE_SOLVER);
222
223 Paso_Copy(n,v_old,v);
224
225 Paso_Update(n,beta,v_old,1,u2);
226 Paso_LinearCombination(n,v,1.,u1,beta,v_old);
227 }
228 maxIterFlag = (num_iter > maxit);
229 norm_of_residual=tau*sqrt ( m + 1 );
230 convergeFlag=(norm_of_residual<(*tolerance));
231
232
233 if (maxIterFlag) {
234 status = SOLVER_MAXITER_REACHED;
235 } else if (breakFlag) {
236 status = SOLVER_BREAKDOWN;
237 }
238 ++(num_iter);
239 }
240 /* end of iteration */
241
242 Performance_stopMonitor(pp,PERFORMANCE_SOLVER);
243 TMPMEMFREE(u1);
244 TMPMEMFREE(u2);
245 TMPMEMFREE(y1);
246 TMPMEMFREE(y2);
247 TMPMEMFREE(d);
248 TMPMEMFREE(w);
249 TMPMEMFREE(v);
250 TMPMEMFREE(v_old);
251
252 *iter=num_iter;
253 *tolerance=norm_of_residual;
254
255 /* End of TFQMR */
256 return status;
257 }

  ViewVC Help
Powered by ViewVC 1.1.26