/[escript]/trunk/paso/src/Pattern_coupling.c
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Contents of /trunk/paso/src/Pattern_coupling.c

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Revision 2450 - (show annotations)
Tue Jun 2 01:22:11 2009 UTC (10 years, 3 months ago) by artak
File MIME type: text/plain
File size: 9948 byte(s)
First version of 'greedy' algorithm for Ruge Stuben and Aggregiation.
1
2 /*******************************************************
3 *
4 * Copyright (c) 2003-2008 by University of Queensland
5 * Earth Systems Science Computational Center (ESSCC)
6 * http://www.uq.edu.au/esscc
7 *
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
15 /**********************************************************************/
16
17 /* Paso: Pattern: Paso_Pattern_coupling
18
19 searches for a maximal independent set MIS in the matrix pattern
20 vertices in the maximal independent set are marked in mis_marker
21 nodes to be considered are marked by -1 on the input in mis_marker
22
23 */
24 /**********************************************************************/
25
26 /* Copyrights by ACcESS Australia 2003,2004,2005 */
27 /* Author: artak@uq.edu.au */
28
29 /**************************************************************/
30
31 #include "PasoUtil.h"
32 #include "Pattern_coupling.h"
33 #include <limits.h>
34
35
36 /***************************************************************/
37
38 #define IS_AVAILABLE -1
39 #define IS_IN_SET -3 /* Week connection */
40 #define IS_REMOVED -4 /* strong */
41
42 void Paso_Pattern_coup(Paso_SparseMatrix* A, index_t* mis_marker, double threshold) {
43
44 dim_t i,j;
45 /*double sum;*/
46 index_t iptr,*index,*where_p,*diagptr;
47 bool_t passed=FALSE;
48 dim_t n=A->numRows;
49 diagptr=MEMALLOC(n,index_t);
50
51 if (A->pattern->type & PATTERN_FORMAT_SYM) {
52 Paso_setError(TYPE_ERROR,"Paso_Pattern_coup: symmetric matrix pattern is not supported yet");
53 return;
54 }
55
56 #pragma omp parallel for private(i) schedule(static)
57 for (i=0;i<n;++i)
58 if(mis_marker[i]==IS_AVAILABLE)
59 mis_marker[i]=IS_IN_SET;
60
61 #pragma omp parallel for private(i,index,where_p) schedule(static)
62 for (i=0;i<n;++i) {
63 diagptr[i]=A->pattern->ptr[i];
64 index=&(A->pattern->index[diagptr[i]]);
65 where_p=(index_t*)bsearch(&i,
66 index,
67 A->pattern->ptr[i + 1]-A->pattern->ptr[i],
68 sizeof(index_t),
69 Paso_comparIndex);
70 if (where_p==NULL) {
71 Paso_setError(VALUE_ERROR, "Paso_Pattern_coup: main diagonal element missing.");
72 } else {
73 diagptr[i]+=(index_t)(where_p-index);
74 }
75 }
76
77
78
79 /*This loop cannot be parallelized, as order matters here.*/
80 for (i=0;i<n;++i) {
81 if (mis_marker[i]==IS_IN_SET) {
82 for (iptr=A->pattern->ptr[i];iptr<A->pattern->ptr[i+1]; ++iptr) {
83 j=A->pattern->index[iptr];
84 if (j!=i && ABS(A->val[iptr])>=threshold*ABS(A->val[diagptr[i]])) {
85 mis_marker[j]=IS_REMOVED;
86 }
87 }
88 }
89 }
90
91
92
93 /*This loop cannot be parallelized, as order matters here.*/
94 for (i=0;i<n;i++) {
95 if (mis_marker[i]==IS_REMOVED) {
96 passed=TRUE;
97 for (iptr=A->pattern->ptr[i];iptr<A->pattern->ptr[i+1]; ++iptr) {
98 j=A->pattern->index[iptr];
99 if (mis_marker[j]==IS_IN_SET) {
100 if ((A->val[iptr]/A->val[diagptr[i]])>=-threshold) {
101 passed=TRUE;
102 }
103 else {
104 passed=FALSE;
105 break;
106 }
107 }
108 }
109 if (passed) mis_marker[i]=IS_IN_SET;
110 }
111 }
112 /* This check is to make sure we dont get some nusty rows which were not removed durring coarsening process.*/
113 /* TODO: we have to mechanism that this does not happend at all, and get rid of this 'If'. */
114 /*#pragma omp parallel for private(i,iptr,j,sum) schedule(static)
115 for (i=0;i<n;i++) {
116 if (mis_marker[i]==IS_REMOVED) {
117 sum=0;
118 for (iptr=A->pattern->ptr[i];iptr<A->pattern->ptr[i+1]; ++iptr) {
119 j=A->pattern->index[iptr];
120 if (mis_marker[j]==IS_REMOVED)
121 sum+=A->val[iptr];
122 }
123 if(ABS(sum)<1.e-25)
124 mis_marker[i]=IS_IN_SET;
125 }
126 }
127 */
128
129 /* swap to TRUE/FALSE in mis_marker */
130 #pragma omp parallel for private(i) schedule(static)
131 for (i=0;i<n;i++) mis_marker[i]=(mis_marker[i]!=IS_IN_SET);
132
133 MEMFREE(diagptr);
134 }
135
136 /*
137 * Ruge-Stueben strength of connection mask.
138 *
139 */
140 void Paso_Pattern_RS(Paso_SparseMatrix* A, index_t* mis_marker, double theta)
141 {
142 dim_t i,n,j;
143 index_t iptr;
144 double threshold,min_offdiagonal;
145
146 Paso_Pattern *out=NULL;
147
148 Paso_IndexList* index_list=NULL;
149
150 index_list=TMPMEMALLOC(A->pattern->numOutput,Paso_IndexList);
151 if (! Paso_checkPtr(index_list)) {
152 #pragma omp parallel for private(i) schedule(static)
153 for(i=0;i<A->pattern->numOutput;++i) {
154 index_list[i].extension=NULL;
155 index_list[i].n=0;
156 }
157 }
158
159
160 n=A->numRows;
161 if (A->pattern->type & PATTERN_FORMAT_SYM) {
162 Paso_setError(TYPE_ERROR,"Paso_Pattern_RS: symmetric matrix pattern is not supported yet");
163 return;
164 }
165
166 #pragma omp parallel for private(i,iptr,min_offdiagonal,threshold) schedule(static)
167 for (i=0;i<n;++i) {
168 if(mis_marker[i]==IS_AVAILABLE) {
169 min_offdiagonal = DBL_MAX;
170 for (iptr=A->pattern->ptr[i];iptr<A->pattern->ptr[i+1]; ++iptr) {
171 if(A->pattern->index[iptr] != i){
172 min_offdiagonal = MIN(min_offdiagonal,A->val[iptr]);
173 }
174 }
175
176 threshold = theta*min_offdiagonal;
177 for (iptr=A->pattern->ptr[i];iptr<A->pattern->ptr[i+1]; ++iptr) {
178 j=A->pattern->index[iptr];
179 if(A->val[iptr]<=threshold) {
180 if(j!=i) {
181 Paso_IndexList_insertIndex(&(index_list[i]),j);
182 Paso_IndexList_insertIndex(&(index_list[j]),i);
183 }
184 }
185 }
186 }
187 }
188
189 out=Paso_IndexList_createPattern(0, A->pattern->numOutput,index_list,0,A->pattern->numInput,0);
190
191 /* clean up */
192 if (index_list!=NULL) {
193 #pragma omp parallel for private(i) schedule(static)
194 for(i=0;i<A->pattern->numOutput;++i) Paso_IndexList_free(index_list[i].extension);
195 }
196 TMPMEMFREE(index_list);
197
198 /*Paso_Pattern_mis(out,mis_marker);*/
199 Paso_Pattern_greedy(out,mis_marker);
200 }
201
202 void Paso_Pattern_Aggregiation(Paso_SparseMatrix* A, index_t* mis_marker, double theta)
203 {
204 dim_t i,j,n;
205 index_t iptr;
206 double diag,eps_Aii,val;
207 double* diags;
208
209
210 Paso_Pattern *out=NULL;
211 Paso_IndexList* index_list=NULL;
212
213 n=A->numRows;
214 diags=MEMALLOC(n,double);
215
216 index_list=TMPMEMALLOC(A->pattern->numOutput,Paso_IndexList);
217 if (! Paso_checkPtr(index_list)) {
218 #pragma omp parallel for private(i) schedule(static)
219 for(i=0;i<A->pattern->numOutput;++i) {
220 index_list[i].extension=NULL;
221 index_list[i].n=0;
222 }
223 }
224
225 if (A->pattern->type & PATTERN_FORMAT_SYM) {
226 Paso_setError(TYPE_ERROR,"Paso_Pattern_Aggregiation: symmetric matrix pattern is not supported yet");
227 return;
228 }
229
230
231 #pragma omp parallel for private(i,iptr,diag) schedule(static)
232 for (i=0;i<n;++i) {
233 diag = 0;
234 for (iptr=A->pattern->ptr[i];iptr<A->pattern->ptr[i+1]; ++iptr) {
235 if(A->pattern->index[iptr] == i){
236 diag+=A->val[iptr];
237 }
238 }
239 diags[i]=ABS(diag);
240 }
241
242
243 #pragma omp parallel for private(i,iptr,j,val,eps_Aii) schedule(static)
244 for (i=0;i<n;++i) {
245 if (mis_marker[i]==IS_AVAILABLE) {
246 eps_Aii = theta*theta*diags[i];
247 val=0.;
248 for (iptr=A->pattern->ptr[i];iptr<A->pattern->ptr[i+1]; ++iptr) {
249 j=A->pattern->index[iptr];
250 val=A->val[iptr];
251 if(j!= i) {
252 if(val*val>=eps_Aii * diags[j]) {
253 Paso_IndexList_insertIndex(&(index_list[i]),j);
254 }
255 }
256 }
257 }
258 }
259
260 out=Paso_IndexList_createPattern(0, A->pattern->numOutput,index_list,0,A->pattern->numInput,0);
261
262 /* clean up */
263 if (index_list!=NULL) {
264 #pragma omp parallel for private(i) schedule(static)
265 for(i=0;i<A->pattern->numOutput;++i) Paso_IndexList_free(index_list[i].extension);
266 }
267
268 TMPMEMFREE(index_list);
269 MEMFREE(diags);
270
271 /*Paso_Pattern_mis(out,mis_marker);*/
272 Paso_Pattern_greedy(out,mis_marker);
273
274 }
275
276 /* Greedy algorithm */
277 void Paso_Pattern_greedy(Paso_Pattern* pattern, index_t* mis_marker) {
278
279 dim_t i,j;
280 /*double sum;*/
281 index_t iptr;
282 bool_t passed=FALSE;
283 dim_t n=pattern->numOutput;
284
285 if (pattern->type & PATTERN_FORMAT_SYM) {
286 Paso_setError(TYPE_ERROR,"Paso_Pattern_greedy: symmetric matrix pattern is not supported yet");
287 return;
288 }
289
290 #pragma omp parallel for private(i) schedule(static)
291 for (i=0;i<n;++i)
292 if(mis_marker[i]==IS_AVAILABLE)
293 mis_marker[i]=IS_IN_SET;
294
295
296 for (i=0;i<n;++i) {
297 if (mis_marker[i]==IS_IN_SET) {
298 for (iptr=pattern->ptr[i];iptr<pattern->ptr[i+1]; ++iptr) {
299 j=pattern->index[iptr];
300 mis_marker[j]=IS_REMOVED;
301 }
302 }
303 }
304
305
306
307 for (i=0;i<n;i++) {
308 if (mis_marker[i]==IS_REMOVED) {
309 passed=TRUE;
310 for (iptr=pattern->ptr[i];iptr<pattern->ptr[i+1]; ++iptr) {
311 j=pattern->index[iptr];
312 if (mis_marker[j]==IS_REMOVED) {
313 passed=TRUE;
314 }
315 else {
316 passed=FALSE;
317 break;
318 }
319 }
320 }
321 if (passed) mis_marker[i]=IS_IN_SET;
322 }
323
324 /* swap to TRUE/FALSE in mis_marker */
325 #pragma omp parallel for private(i) schedule(static)
326 for (i=0;i<n;i++) mis_marker[i]=(mis_marker[i]!=IS_IN_SET);
327
328 }
329
330
331
332
333 #undef IS_AVAILABLE
334 #undef IS_IN_SET
335 #undef IS_REMOVED

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