Scippy

SCIP

Solving Constraint Integer Programs

heur_cycgreedy.c
Go to the documentation of this file.
1 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
2 /* */
3 /* This file is part of the program and library */
4 /* SCIP --- Solving Constraint Integer Programs */
5 /* */
6 /* Copyright (c) 2002-2024 Zuse Institute Berlin (ZIB) */
7 /* */
8 /* Licensed under the Apache License, Version 2.0 (the "License"); */
9 /* you may not use this file except in compliance with the License. */
10 /* You may obtain a copy of the License at */
11 /* */
12 /* http://www.apache.org/licenses/LICENSE-2.0 */
13 /* */
14 /* Unless required by applicable law or agreed to in writing, software */
15 /* distributed under the License is distributed on an "AS IS" BASIS, */
16 /* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. */
17 /* See the License for the specific language governing permissions and */
18 /* limitations under the License. */
19 /* */
20 /* You should have received a copy of the Apache-2.0 license */
21 /* along with SCIP; see the file LICENSE. If not visit scipopt.org. */
22 /* */
23 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
24 
25 /**@file heur_cycgreedy.c
26  * @brief Greedy primal heuristic. States are assigned to clusters iteratively. At each iteration all possible
27  * assignments are computed and the one with the best change in objective value is selected.
28  * @author Leon Eifler
29  */
30 
31 #include "heur_cycgreedy.h"
32 
33 #include <assert.h>
34 #include <string.h>
35 #include <time.h>
36 #include <stdlib.h>
37 #include "scip/misc.h"
38 #include "probdata_cyc.h"
39 #include "scip/cons_and.h"
40 
41 #define HEUR_NAME "cycgreedy"
42 #define HEUR_DESC "primal heuristic template"
43 #define HEUR_DISPCHAR 'h'
44 #define HEUR_PRIORITY 536870911
45 #define HEUR_FREQ 1
46 #define HEUR_FREQOFS 0
47 #define HEUR_MAXDEPTH -1
48 #define HEUR_TIMING SCIP_HEURTIMING_BEFORENODE
49 #define HEUR_USESSUBSCIP FALSE /**< does the heuristic use a secondary SCIP instance? */
50 
51 /** primal heuristic data */
52 struct SCIP_HeurData
53 {
54  int lasteffectrootdepth;/**< index of the last solution for which oneopt was performed */
55  SCIP_Bool local; /**< the heuristic only computes assignments until any improvement is found */
56 };
57 
58 /** calculate the current objective value for a q-matrix */
59 static
61  SCIP* scip, /**< SCIP data structure */
62  SCIP_Real** qmatrix, /**< the irreversibility matrix*/
63  SCIP_Real scale, /**< the scaling parameter in the objective function */
64  int ncluster /**< the number of cluster*/
65  )
66 {
67  SCIP_Real objective = 0.0;
68  int c;
69  int c2;
70 
71  for( c = 0; c < ncluster; ++c )
72  {
73  c2 = ( c + 1 ) % ncluster;
74  objective += qmatrix[c][c2] - qmatrix[c2][c];
75  objective += scale * qmatrix[c][c];
76  }
77 
78  /* if we have no transitions at all then irreversibility should be set to 0 */
79  return objective;
80 }
81 
82 /** initialize the q-matrix from a given (possibly incomplete) clusterassignment */
83 static
85  SCIP_Real** clusterassignment, /**< the matrix containing the (incomplete) clusterassignment */
86  SCIP_Real** qmatrix, /**< the returned matrix with the irreversibility between two clusters */
87  SCIP_Real** cmatrix, /**< the transition-matrix containg the probability-data */
88  int nbins, /**< the number of bins */
89  int ncluster /**< the number of possible clusters */
90  )
91 {
92  int i;
93  int j;
94  int k;
95  int l;
96 
97  for( k = 0; k < ncluster; ++k )
98  {
99  for( l = 0; l < ncluster; ++l )
100  {
101  qmatrix[k][l] = 0;
102 
103  for( i = 0; i < nbins; ++i )
104  {
105  for( j = 0; j < nbins; ++j )
106  {
107  /* as -1 and 0 are both interpreted as 0, this check is necessary. Compute x_ik*x_jl*c_ij */
108  if( clusterassignment[i][k] < 1 || clusterassignment[j][l] < 1 )
109  continue;
110 
111  qmatrix[k][l] += cmatrix[i][j];
112  }
113  }
114  }
115  }
116 }
117 
118 /** update the irreversibility matrix, after the clusterassignment[newcluster][newbin] was either set
119  * from 0 to 1 or from 1 to 0
120  */
121 static
123  SCIP_Real** clusterassignment, /**< the matrix containing the (incomplete) clusterassignment */
124  SCIP_Real** qmatrix, /**< the returned matrix with the irreversibility between two clusters */
125  SCIP_Real** cmatrix, /**< the transition-matrix containg the probability-data */
126  int newbin, /**< the bin to be added to the assignment */
127  int newcluster, /**< the bluster in which the bin was changed */
128  int nbins, /**< the number of bins */
129  int ncluster /**< the number of clusters */
130  )
131 {
132  int bin;
133  int cluster;
134 
135  for( cluster = 0; cluster < ncluster; ++cluster )
136  {
137  for( bin = 0; bin < nbins; ++bin )
138  {
139  /* multiplier is 1 if clusterassignment is 1, and 0 if it is 0 (set to 0) or -1 (unassigned) */
140  int temp = 0;
141  if( clusterassignment[bin][cluster] == 1 )
142  temp = 1;
143 
144  if( cluster != newcluster )
145  {
146  qmatrix[newcluster][cluster] += temp * cmatrix[newbin][bin];
147  qmatrix[cluster][newcluster] += temp * cmatrix[bin][newbin];
148  }
149  else
150  {
151  if( bin == newbin )
152  qmatrix[newcluster][newcluster] += cmatrix[newbin][bin];
153  else
154  qmatrix[newcluster][newcluster] += (cmatrix[newbin][bin] + cmatrix[bin][newbin]) * temp;
155  }
156  }
157  }
158 }
159 
160 /** get the temporary objective value bound after newbin would be added to newcluster
161  * but dont not change anything with the clustering
162  */
163 static
165  SCIP* scip, /**< SCIP data structure */
166  SCIP_Real** qmatrix, /**< the irreversibility matrix */
167  SCIP_Real** cmatrix, /**< the transition matrix */
168  SCIP_Real** clusterassignment, /**< the clusterassignment */
169  int newbin, /**< the bin that would be added to cluster */
170  int newcluster, /**< the cluster the bin would be added to */
171  int nbins, /**< the number of bins */
172  int ncluster /**< the number of cluster */
173  )
174 {
175  SCIP_Real obj;
176  SCIP_Real temp;
177  int i;
178 
179  obj = getObjective(scip, qmatrix, SCIPcycGetScale(scip), ncluster);
180 
181  /* the coh in cluster changes as well as the flow to the next and the previous cluster */
182  for( i = 0; i < nbins; ++i )
183  {
184  temp = (clusterassignment[i][phiinv(newcluster, ncluster)] < 1 ? 0 : 1);
185  obj += (cmatrix[i][newbin] - cmatrix[newbin][i]) * temp;
186  temp = (clusterassignment[i][phi(newcluster, ncluster)] < 1 ? 0 : 1);
187  obj -= (cmatrix[i][newbin] - cmatrix[newbin][i]) * temp;
188  temp = (clusterassignment[i][newcluster] < 1 ? 0 : 1);
189  obj += (cmatrix[i][newbin] + cmatrix[newbin][i]) * temp;
190  }
191 
192  return obj;
193 }
194 
195 /* find and assign the next unassigned bin to an appropriate cluster */
196 static
198  SCIP* scip, /**< SCIP data structure */
199  SCIP_Bool localheur, /**< should the heuristic only compute local optimal assignment */
200  SCIP_Real** clusterassignment, /**< the matrix with the Clusterassignment */
201  SCIP_Real** cmatrix, /**< the transition matrix */
202  SCIP_Real** qmatrix, /**< the irreversibility matrix */
203  SCIP_Bool* isassigned, /**< TRUE, if the bin i was already assigned to a cluster*/
204  int nbins, /**< the number of bins*/
205  int ncluster, /**< the number of cluster*/
206  int* amountassigned, /**< the total amount of bins already assigned*/
207  int* binsincluster, /**< the number of bins currently in a cluster*/
208  SCIP_Real* objective /**< the objective */
209  )
210 {
211  SCIP_Real* binobjective;
212  SCIP_Bool** clusterispossible;
213  int* bestcluster;
214  SCIP_Real tempobj;
215  SCIP_Real max = -SCIPinfinity(scip);
216  int i;
217  int c;
218  int c1;
219  int c2;
220  int save = -1;
221  int ind = -1;
222 
223  /* allocate memory */
224  SCIP_CALL( SCIPallocClearBufferArray(scip, &binobjective, nbins) );
225  SCIP_CALL( SCIPallocClearBufferArray(scip, &bestcluster, nbins) );
226  SCIP_CALL( SCIPallocClearBufferArray(scip, &clusterispossible, nbins) );
227 
228  for( i = 0; i < nbins; ++i )
229  {
230  SCIP_CALL( SCIPallocClearBufferArray(scip, &clusterispossible[i], ncluster) ); /*lint !e866*/
231  }
232 
233  /* make ceratin that each cluster is non-empty*/
234  for( c = 0; c < ncluster; ++c )
235  {
236  tempobj = 0;
237 
238  if( binsincluster[c] == 0 )
239  {
240  for( i = 0; i < nbins; ++i )
241  {
242  /* if already assigned do nothing */
243  if( isassigned[i] )
244  continue;
245 
246  /* check if assigning this state is better than the previous best state */
247  binobjective[i] = getTempObj(scip, qmatrix, cmatrix, clusterassignment, i, c, nbins, ncluster);
248 
249  if( binobjective[i] > tempobj )
250  {
251  save = i;
252  tempobj = binobjective[i];
253  }
254 
255  /* ensure that a state is assigned */
256  if( save == -1 )
257  save = i;
258  }
259 
260  /* assign the found state to the cluster */
261  for( c1 = 0; c1 < ncluster; ++c1 )
262  {
263  clusterassignment[save][c1] = 0;
264  }
265 
266  clusterassignment[save][c] = 1;
267  binsincluster[c]++;
268 
269  assert(binsincluster[c] == 1);
270 
271  isassigned[save] = TRUE;
272  *amountassigned += 1;
273 
274  /* update the q-matrix */
275  updateIrrevMat(clusterassignment, qmatrix, cmatrix, save, c, nbins, ncluster);
276  }
277  }
278 
279  /*phase 2: iteratively assign states such that at each iteration the highest objective improvement is achieved */
280  for( i = 0; i < nbins; ++i )
281  {
282  bestcluster[i] = 0;
283  binobjective[i] = -SCIPinfinity(scip);
284  }
285 
286  for( i = 0; i < nbins; ++i )
287  {
288  if( isassigned[i] )
289  continue;
290 
291  /* check which clusters the bin can be assigned to. -1 means unassigned, 0 means fixed to 0. */
292  for( c1 = 0; c1 < ncluster; ++c1 )
293  {
294  /* if assignment to i would violate abs-var assignment then set clusterpossible to FALSE */
295  if( 0 != clusterassignment[i][c1] )
296  clusterispossible[i][c1] = TRUE;
297  else
298  clusterispossible[i][c1] = FALSE;
299  }
300 
301  /* calculate the irrevbound for all possible clusterassignments */
302  for( c2 = 0; c2 < ncluster; ++c2 )
303  {
304  if( !clusterispossible[i][c2] || clusterassignment[i][c2] == 0 )
305  continue;
306 
307  /* temporarily assign i to c2 */
308  save = (int) clusterassignment[i][c2];
309  clusterassignment[i][c2] = 1;
310 
311  /* save the best possible irrevbound for each bin */
312  tempobj = getTempObj(scip, qmatrix, cmatrix, clusterassignment, i, c2, nbins, ncluster);
313 
314  /* check if this is an improvement compared to the best known assignment */
315  if( SCIPisGT(scip, tempobj, binobjective[i]) )
316  {
317  binobjective[i] = tempobj;
318  bestcluster[i] = c2;
319  }
320 
321  clusterassignment[i][c2] = save;
322  }
323 
324  /* if localheur is true, then the heuristic assigns a state as soon as any improvement is found */
325  if( localheur && SCIPisGT(scip, binobjective[i], *objective) )
326  break;
327  }
328 
329  /* take the bin with the highest increase in irrev-bound */
330  for( i = 0; i < nbins; ++i )
331  {
332  if( SCIPisLT(scip, max, binobjective[i]) )
333  {
334  max = binobjective[i];
335  ind = i;
336  }
337  }
338 
339  assert(!isassigned[ind] && ind > -1 && ind < nbins);
340 
341  /* assign this bin to the found cluster */
342  for( c1 = 0; c1 < ncluster; ++c1 )
343  {
344  clusterassignment[ind][c1] = 0;
345  }
346 
347  clusterassignment[ind][bestcluster[ind]] = 1;
348  binsincluster[bestcluster[ind]]++;
349  *amountassigned += 1;
350  isassigned[ind] = TRUE;
351 
352  /* update the Irreversibility matrix */
353  updateIrrevMat(clusterassignment, qmatrix, cmatrix, ind, bestcluster[ind], nbins, ncluster);
354  *objective = getObjective(scip, qmatrix, SCIPcycGetScale(scip), ncluster);
355 
356  /* free the allocated memory */
357  for( i = 0; i < nbins; ++i )
358  {
359  SCIPfreeBufferArray(scip, &(clusterispossible[i]));
360  }
361  SCIPfreeBufferArray(scip, &clusterispossible);
362  SCIPfreeBufferArray(scip, &bestcluster);
363  SCIPfreeBufferArray(scip, &binobjective);
364 
365  return SCIP_OKAY;
366 }
367 
368 /*
369  * Callback methods of primal heuristic
370  */
371 
372 /** copy method for primal heuristic plugins (called when SCIP copies plugins) */
373 static
374 SCIP_DECL_HEURCOPY(heurCopyCycGreedy)
375 { /*lint --e{715}*/
376  assert(scip != NULL);
377  assert(heur != NULL);
378  assert(strcmp(SCIPheurGetName(heur), HEUR_NAME) == 0);
379 
380  /* call inclusion method of primal heuristic */
382 
383  return SCIP_OKAY;
384 }
385 
386 /** destructor of primal heuristic to free user data (called when SCIP is exiting) */
387 static
388 SCIP_DECL_HEURFREE(heurFreeCycGreedy)
389 { /*lint --e{715}*/
390  SCIP_HEURDATA* heurdata;
391 
392  assert(heur != NULL);
393  assert(strcmp(SCIPheurGetName(heur), HEUR_NAME) == 0);
394  assert(scip != NULL);
395 
396  /* free heuristic data */
397  heurdata = SCIPheurGetData(heur);
398 
399  assert(heurdata != NULL);
400 
401  SCIPfreeMemory(scip, &heurdata);
402  SCIPheurSetData(heur, NULL);
403 
404  return SCIP_OKAY;
405 }
406 
407 /** solving process deinitialization method of primal heuristic (called before branch and bound process data is freed) */
408 static
409 SCIP_DECL_HEUREXITSOL(heurExitsolCycGreedy)
410 { /*lint --e{715}*/
411  assert(heur != NULL);
412  assert(strcmp(SCIPheurGetName(heur), HEUR_NAME) == 0);
413 
414  /* reset the timing mask to its default value */
416 
417  return SCIP_OKAY;
418 }
419 
420 /** initialization method of primal heuristic (called after problem was transformed) */
421 static
422 SCIP_DECL_HEURINIT(heurInitCycGreedy)
423 { /*lint --e{715}*/
424  SCIP_HEURDATA* heurdata;
425 
426  assert(heur != NULL);
427  assert(scip != NULL);
428 
429  /* get heuristic data */
430  heurdata = SCIPheurGetData(heur);
431  assert(heurdata != NULL);
432 
433  /* initialize last solution index */
434  heurdata->lasteffectrootdepth = -1;
435 
436  return SCIP_OKAY;
437 }
438 
439 /** execution method of primal heuristic */
440 static
441 SCIP_DECL_HEUREXEC(heurExecCycGreedy)
442 { /*lint --e{715}*/
443  SCIP_Real** cmatrix; /* the transition matrixx */
444  SCIP_Real** qmatrix; /* the low-dimensional transition matrix between clusters */
445  SCIP_VAR*** binvars; /* SCIP variables */
446  SCIP_Real** clustering; /* matrix for the assignment of the binary variables */
447  int* binsincluster; /* amount of bins in a given cluster */
448  SCIP_Bool* isassigned; /* TRUE if a bin has already bin assigned to a cluster */
449  SCIP_HEURDATA* heurdata; /* the heurdata */
450  SCIP_SOL* sol; /* pointer to solution */
451  SCIP_Bool possible = TRUE; /* can the heuristic be run */
452  SCIP_Bool feasible = FALSE; /* is the solution feasible */
453  SCIP_Real obj = 0.0; /* objective value */
454  int amountassigned; /* total amount of bins assigned */
455  int nbins; /* number of bins */
456  int ncluster; /* number of cluster */
457  int i; /* running indices */
458  int j;
459  int c;
460 
461  *result = SCIP_DIDNOTRUN;
462  amountassigned = 0;
463 
464  /* for now: do not use heurisitc if weighted objective is used */
465  heurdata = SCIPheurGetData(heur);
466  if( SCIPgetEffectiveRootDepth(scip) == heurdata->lasteffectrootdepth )
467  return SCIP_OKAY;
468 
469  heurdata->lasteffectrootdepth = SCIPgetEffectiveRootDepth(scip);
470 
471  /* get the problem data from scip */
472  cmatrix = SCIPcycGetCmatrix(scip);
473  nbins = SCIPcycGetNBins(scip);
474  ncluster = SCIPcycGetNCluster(scip);
475  binvars = SCIPcycGetBinvars(scip);
476 
477  assert(nbins > 0 && ncluster > 0);
478 
479  /* allocate memory for the assignment */
480  SCIP_CALL( SCIPallocClearBufferArray(scip, &clustering, nbins) );
481  SCIP_CALL( SCIPallocClearBufferArray(scip, &binsincluster, ncluster) );
482  SCIP_CALL( SCIPallocClearBufferArray(scip, &qmatrix, ncluster) );
483  SCIP_CALL( SCIPallocClearBufferArray(scip, &isassigned, nbins) );
484 
485  for ( i = 0; i < nbins; ++i )
486  {
487  if( i < ncluster )
488  {
489  SCIP_CALL( SCIPallocClearBufferArray(scip, &qmatrix[i], ncluster) ); /*lint !e866*/
490  }
491 
492  SCIP_CALL( SCIPallocClearBufferArray(scip, &clustering[i], ncluster) ); /*lint !e866*/
493 
494  for( j = 0; j < ncluster; ++j )
495  {
496  /* unassigned is set to -1 so we can differentiate unassigned and fixed in the branch and bound tree */
497  clustering[i][j] = -1;
498  }
499  }
500 
501  /* get the already fixed bin-variables from scip. An assignment of -1 one means unassigned.
502  * 0 is fixed to 0, 1 is fixed to 1
503  */
504  for( i = 0; i < nbins; ++i )
505  {
506  for( j = 0; j < ncluster; ++j )
507  {
508  if( NULL == binvars[i][j] )
509  {
510  possible = FALSE;
511  break;
512  }
513 
514  /* if the bounds determine a fixed binary variable, then fix the variable in the clusterassignment */
515  if( SCIPisEQ(scip, SCIPvarGetLbGlobal(binvars[i][j]), SCIPvarGetUbGlobal(binvars[i][j])) )
516  {
517  clustering[i][j] = SCIPvarGetLbGlobal(binvars[i][j]);
518 
519  if( SCIPisEQ(scip, 1.0, clustering[i][j]) )
520  {
521  binsincluster[j]++;
522  isassigned[i] = TRUE;
523  amountassigned += 1;
524 
525  for( c = 0; c < ncluster; ++c )
526  {
527  if( clustering[i][c] == -1 )
528  clustering[i][c] = 0;
529  }
530  }
531  }
532  }
533  }
534 
535  /* check if the assignment violates paritioning, e.g. because we are in a subscip */
536  for( i = 0; i < nbins; ++i )
537  {
538  int amountzeros = 0;
539  int sum = 0;
540 
541  for( j = 0; j < ncluster; ++j )
542  {
543  if( 0 == clustering[i][j] )
544  amountzeros++;
545  if( 1 == clustering[i][j] )
546  sum++;
547  }
548 
549  if( ncluster == amountzeros || sum > 1 )
550  possible = FALSE;
551  }
552 
553  if( amountassigned < nbins && possible )
554  {
555  /* initialize the qmatrix and the lower irreversibility bound */
556  computeIrrevMat(clustering, qmatrix, cmatrix, nbins, ncluster);
557  obj = getObjective(scip, qmatrix, SCIPcycGetScale(scip), ncluster);
558 
559  /* assign bins iteratively until all bins are assigned */
560  while( amountassigned < nbins )
561  {
562  SCIP_CALL( assignNextBin(scip, heurdata->local, clustering, cmatrix, qmatrix,
563  isassigned, nbins, ncluster, &amountassigned, binsincluster, &obj ) );
564  }
565 
566  /* assert that the assignment is valid in the sense that it is a partition of the bins.
567  * Feasibility is not checked in this method
568  */
569  assert(isPartition(scip,clustering, nbins, ncluster));
570 
571  /* update the qmatrix */
572  computeIrrevMat(clustering, qmatrix, cmatrix, nbins, ncluster);
573 
574  /* set the variables the problem to the found clustering and test feasibility */
575  SCIP_CALL( SCIPcreateSol(scip, &sol, heur) );
576  SCIP_CALL( assignVars( scip, sol, clustering, nbins, ncluster) );
577  SCIP_CALL( SCIPtrySolFree(scip, &sol, FALSE, TRUE, TRUE, TRUE, TRUE, &feasible) );
578  }
579 
580  if( feasible )
581  *result = SCIP_FOUNDSOL;
582  else
583  *result = SCIP_DIDNOTFIND;
584 
585  /* free allocated memory */
586  for ( i = 0; i < nbins; ++i )
587  {
588  SCIPfreeBufferArray(scip, &clustering[i]);
589 
590  if( i < ncluster )
591  SCIPfreeBufferArray(scip, &qmatrix[i]);
592  }
593 
594  SCIPfreeBufferArray(scip, &isassigned);
595  SCIPfreeBufferArray(scip, &qmatrix);
596  SCIPfreeBufferArray(scip, &binsincluster);
597  SCIPfreeBufferArray(scip, &clustering);
598 
599  return SCIP_OKAY;
600 }
601 
602 /*
603  * * primal heuristic specific interface methods
604  */
605 
606 /** creates the CycGreedy - primal heuristic and includes it in SCIP */
608  SCIP* scip /**< SCIP data structure */
609  )
610 {
611  SCIP_HEURDATA* heurdata;
612  SCIP_HEUR* heur;
613 
614  /* create greedy primal heuristic data */
615  SCIP_CALL( SCIPallocMemory(scip, &heurdata) );
616 
617  /* include primal heuristic */
618 
619  SCIP_CALL( SCIPincludeHeurBasic(scip, &heur,
621  HEUR_MAXDEPTH, HEUR_TIMING, HEUR_USESSUBSCIP, heurExecCycGreedy, heurdata) );
622 
623  assert(heur != NULL);
624 
625  /* set non fundamental callbacks via setter functions */
626  SCIP_CALL( SCIPsetHeurCopy(scip, heur, heurCopyCycGreedy) );
627  SCIP_CALL( SCIPsetHeurFree(scip, heur, heurFreeCycGreedy) );
628  SCIP_CALL( SCIPsetHeurExitsol(scip, heur, heurExitsolCycGreedy) );
629  SCIP_CALL( SCIPsetHeurInit(scip, heur, heurInitCycGreedy) );
630 
632  "localheur", "If set to true, heuristic assigns bins as soon as any improvement is found",
633  &heurdata->local, FALSE, TRUE, NULL, NULL) );
634 
635  return SCIP_OKAY;
636 }
SCIP_RETCODE SCIPsetHeurExitsol(SCIP *scip, SCIP_HEUR *heur, SCIP_DECL_HEUREXITSOL((*heurexitsol)))
Definition: scip_heur.c:242
#define NULL
Definition: def.h:267
static SCIP_RETCODE assignNextBin(SCIP *scip, SCIP_Bool localheur, SCIP_Real **clusterassignment, SCIP_Real **cmatrix, SCIP_Real **qmatrix, SCIP_Bool *isassigned, int nbins, int ncluster, int *amountassigned, int *binsincluster, SCIP_Real *objective)
static void computeIrrevMat(SCIP_Real **clusterassignment, SCIP_Real **qmatrix, SCIP_Real **cmatrix, int nbins, int ncluster)
#define SCIPallocClearBufferArray(scip, ptr, num)
Definition: scip_mem.h:126
SCIP_Real SCIPvarGetLbGlobal(SCIP_VAR *var)
Definition: var.c:18079
SCIP_RETCODE assignVars(SCIP *scip, SCIP_SOL *sol, SCIP_Real **clustering, int nbins, int ncluster)
Definition: probdata_cyc.c:88
static void updateIrrevMat(SCIP_Real **clusterassignment, SCIP_Real **qmatrix, SCIP_Real **cmatrix, int newbin, int newcluster, int nbins, int ncluster)
#define FALSE
Definition: def.h:94
SCIP_Real SCIPinfinity(SCIP *scip)
#define TRUE
Definition: def.h:93
#define HEUR_USESSUBSCIP
enum SCIP_Retcode SCIP_RETCODE
Definition: type_retcode.h:63
struct SCIP_HeurData SCIP_HEURDATA
Definition: type_heur.h:77
SCIP_RETCODE SCIPincludeHeurBasic(SCIP *scip, SCIP_HEUR **heur, const char *name, const char *desc, char dispchar, int priority, int freq, int freqofs, int maxdepth, SCIP_HEURTIMING timingmask, SCIP_Bool usessubscip, SCIP_DECL_HEUREXEC((*heurexec)), SCIP_HEURDATA *heurdata)
Definition: scip_heur.c:117
SCIP_Real SCIPcycGetScale(SCIP *scip)
Constraint handler for AND constraints, .
SCIP_Bool SCIPisEQ(SCIP *scip, SCIP_Real val1, SCIP_Real val2)
#define SCIPfreeBufferArray(scip, ptr)
Definition: scip_mem.h:136
void SCIPheurSetData(SCIP_HEUR *heur, SCIP_HEURDATA *heurdata)
Definition: heur.c:1374
#define HEUR_DISPCHAR
static SCIP_Real getObjective(SCIP *scip, SCIP_Real **qmatrix, SCIP_Real scale, int ncluster)
#define HEUR_FREQOFS
SCIP_Real SCIPvarGetUbGlobal(SCIP_VAR *var)
Definition: var.c:18089
const char * SCIPheurGetName(SCIP_HEUR *heur)
Definition: heur.c:1453
#define HEUR_NAME
SCIP_RETCODE SCIPsetHeurFree(SCIP *scip, SCIP_HEUR *heur, SCIP_DECL_HEURFREE((*heurfree)))
Definition: scip_heur.c:178
SCIP_Bool SCIPisLT(SCIP *scip, SCIP_Real val1, SCIP_Real val2)
#define HEUR_TIMING
static SCIP_Real getTempObj(SCIP *scip, SCIP_Real **qmatrix, SCIP_Real **cmatrix, SCIP_Real **clusterassignment, int newbin, int newcluster, int nbins, int ncluster)
static SCIP_Real phi(SCIP *scip, SCIP_Real val, SCIP_Real lb, SCIP_Real ub)
Definition: sepa_eccuts.c:846
internal miscellaneous methods
#define HEUR_MAXDEPTH
SCIP_RETCODE SCIPincludeHeurCycGreedy(SCIP *scip)
int SCIPgetEffectiveRootDepth(SCIP *scip)
Definition: scip_tree.c:127
#define SCIP_CALL(x)
Definition: def.h:380
int SCIPcycGetNBins(SCIP *scip)
int phiinv(int k, int ncluster)
Definition: probdata_cyc.c:193
#define SCIP_Bool
Definition: def.h:91
static SCIP_DECL_HEURCOPY(heurCopyCycGreedy)
static SCIP_DECL_HEUREXEC(heurExecCycGreedy)
SCIP_RETCODE SCIPtrySolFree(SCIP *scip, SCIP_SOL **sol, SCIP_Bool printreason, SCIP_Bool completely, SCIP_Bool checkbounds, SCIP_Bool checkintegrality, SCIP_Bool checklprows, SCIP_Bool *stored)
Definition: scip_sol.c:3050
#define HEUR_PRIORITY
problem data for cycle clustering problem
#define SCIPfreeMemory(scip, ptr)
Definition: scip_mem.h:78
#define HEUR_DESC
SCIP_Bool SCIPisGT(SCIP *scip, SCIP_Real val1, SCIP_Real val2)
int SCIPcycGetNCluster(SCIP *scip)
static SCIP_DECL_HEURINIT(heurInitCycGreedy)
SCIP_RETCODE SCIPsetHeurInit(SCIP *scip, SCIP_HEUR *heur, SCIP_DECL_HEURINIT((*heurinit)))
Definition: scip_heur.c:194
#define SCIP_Real
Definition: def.h:173
void SCIPheurSetTimingmask(SCIP_HEUR *heur, SCIP_HEURTIMING timingmask)
Definition: heur.c:1493
#define SCIPallocMemory(scip, ptr)
Definition: scip_mem.h:60
Greedy primal heuristic. States are assigned to clusters iteratively. At each iteration all possible ...
SCIP_RETCODE SCIPsetHeurCopy(SCIP *scip, SCIP_HEUR *heur, SCIP_DECL_HEURCOPY((*heurcopy)))
Definition: scip_heur.c:162
static SCIP_DECL_HEUREXITSOL(heurExitsolCycGreedy)
#define HEUR_FREQ
SCIP_Bool isPartition(SCIP *scip, SCIP_Real **solclustering, int nbins, int ncluster)
Definition: probdata_cyc.c:57
static SCIP_DECL_HEURFREE(heurFreeCycGreedy)
SCIP_HEURDATA * SCIPheurGetData(SCIP_HEUR *heur)
Definition: heur.c:1364
SCIP_VAR *** SCIPcycGetBinvars(SCIP *scip)
SCIP_Real ** SCIPcycGetCmatrix(SCIP *scip)
SCIP_RETCODE SCIPaddBoolParam(SCIP *scip, const char *name, const char *desc, SCIP_Bool *valueptr, SCIP_Bool isadvanced, SCIP_Bool defaultvalue, SCIP_DECL_PARAMCHGD((*paramchgd)), SCIP_PARAMDATA *paramdata)
Definition: scip_param.c:57
SCIP_RETCODE SCIPcreateSol(SCIP *scip, SCIP_SOL **sol, SCIP_HEUR *heur)
Definition: scip_sol.c:184