Scippy

SCIP

Solving Constraint Integer Programs

scip_solve.h
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) 2002-2023 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 scip_solve.h
26  * @ingroup PUBLICCOREAPI
27  * @brief public solving methods
28  * @author Tobias Achterberg
29  * @author Timo Berthold
30  * @author Thorsten Koch
31  * @author Alexander Martin
32  * @author Marc Pfetsch
33  * @author Kati Wolter
34  * @author Gregor Hendel
35  * @author Leona Gottwald
36  */
37 
38 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
39 
40 #ifndef __SCIP_SCIP_SOLVE_H__
41 #define __SCIP_SCIP_SOLVE_H__
42 
43 
44 #include "scip/def.h"
45 #include "scip/type_retcode.h"
46 #include "scip/type_scip.h"
47 #include "scip/type_sol.h"
48 #include "scip/type_tree.h"
49 #include "scip/type_var.h"
50 
51 #ifdef __cplusplus
52 extern "C" {
53 #endif
54 
55 /**@addtogroup PublicSolveMethods
56  *
57  * @{
58  */
59 
60 /** initializes solving data structures and transforms problem
61  *
62  * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
63  * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
64  *
65  * @pre This method can be called if @p scip is in one of the following stages:
66  * - \ref SCIP_STAGE_PROBLEM
67  * - \ref SCIP_STAGE_TRANSFORMED
68  * - \ref SCIP_STAGE_INITPRESOLVE
69  * - \ref SCIP_STAGE_PRESOLVING
70  * - \ref SCIP_STAGE_EXITPRESOLVE
71  * - \ref SCIP_STAGE_PRESOLVED
72  * - \ref SCIP_STAGE_INITSOLVE
73  * - \ref SCIP_STAGE_SOLVING
74  * - \ref SCIP_STAGE_SOLVED
75  * - \ref SCIP_STAGE_EXITSOLVE
76  * - \ref SCIP_STAGE_FREETRANS
77  * - \ref SCIP_STAGE_FREE
78  *
79  * @post When calling this method in the \ref SCIP_STAGE_PROBLEM stage, the \SCIP stage is changed to \ref
80  * SCIP_STAGE_TRANSFORMED; otherwise, the stage is not changed
81  *
82  * See \ref SCIP_Stage "SCIP_STAGE" for a complete list of all possible solving stages.
83  */
84 SCIP_EXPORT
86  SCIP* scip /**< SCIP data structure */
87  );
88 
89 /** transforms and presolves problem
90  *
91  * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
92  * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
93  *
94  * @pre This method can be called if @p scip is in one of the following stages:
95  * - \ref SCIP_STAGE_PROBLEM
96  * - \ref SCIP_STAGE_TRANSFORMED
97  * - \ref SCIP_STAGE_PRESOLVING
98  * - \ref SCIP_STAGE_PRESOLVED
99  * - \ref SCIP_STAGE_SOLVED
100  *
101  * @post After calling this method \SCIP reaches one of the following stages:
102  * - \ref SCIP_STAGE_PRESOLVING if the presolving process was interrupted
103  * - \ref SCIP_STAGE_PRESOLVED if the presolving process was finished and did not solve the problem
104  * - \ref SCIP_STAGE_SOLVED if the problem was solved during presolving
105  *
106  * See \ref SCIP_Stage "SCIP_STAGE" for a complete list of all possible solving stages.
107  */
108 SCIP_EXPORT
110  SCIP* scip /**< SCIP data structure */
111  );
112 
113 /** transforms, presolves, and solves problem
114  *
115  * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
116  * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
117  *
118  * @pre This method can be called if @p scip is in one of the following stages:
119  * - \ref SCIP_STAGE_PROBLEM
120  * - \ref SCIP_STAGE_TRANSFORMED
121  * - \ref SCIP_STAGE_PRESOLVING
122  * - \ref SCIP_STAGE_PRESOLVED
123  * - \ref SCIP_STAGE_SOLVING
124  * - \ref SCIP_STAGE_SOLVED
125  *
126  * @post After calling this method \SCIP reaches one of the following stages depending on if and when the solution
127  * process was interrupted:
128 
129  * - \ref SCIP_STAGE_PRESOLVING if the solution process was interrupted during presolving
130  * - \ref SCIP_STAGE_SOLVING if the solution process was interrupted during the tree search
131  * - \ref SCIP_STAGE_SOLVED if the solving process was not interrupted
132  *
133  * See \ref SCIP_Stage "SCIP_STAGE" for a complete list of all possible solving stages.
134  */
135 SCIP_EXPORT
137  SCIP* scip /**< SCIP data structure */
138  );
139 
140 /** transforms, presolves, and solves problem using additional solvers which emphasize on
141  * finding solutions.
142  *
143  * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
144  * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
145  *
146  * @pre This method can be called if @p scip is in one of the following stages:
147  * - \ref SCIP_STAGE_PROBLEM
148  * - \ref SCIP_STAGE_TRANSFORMED
149  * - \ref SCIP_STAGE_PRESOLVING
150  * - \ref SCIP_STAGE_PRESOLVED
151  * - \ref SCIP_STAGE_SOLVING
152  * - \ref SCIP_STAGE_SOLVED
153  *
154  * @post After calling this method \SCIP reaches one of the following stages depending on if and when the solution
155  * process was interrupted:
156  * - \ref SCIP_STAGE_PRESOLVING if the solution process was interrupted during presolving
157  * - \ref SCIP_STAGE_SOLVING if the solution process was interrupted during the tree search
158  * - \ref SCIP_STAGE_SOLVED if the solving process was not interrupted
159  *
160  * See \ref SCIP_Stage "SCIP_STAGE" for a complete list of all possible solving stages.
161  *
162  * @deprecated Please use SCIPsolveConcurrent() instead.
163  */
164 SCIP_EXPORT
166  SCIP* scip /**< SCIP data structure */
167  );
168 
169 /** transforms, presolves, and solves problem using additional solvers which emphasize on
170  * finding solutions.
171  *
172  * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
173  * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
174  *
175  * @pre This method can be called if @p scip is in one of the following stages:
176  * - \ref SCIP_STAGE_PROBLEM
177  * - \ref SCIP_STAGE_TRANSFORMED
178  * - \ref SCIP_STAGE_PRESOLVING
179  * - \ref SCIP_STAGE_PRESOLVED
180  * - \ref SCIP_STAGE_SOLVING
181  * - \ref SCIP_STAGE_SOLVED
182  *
183  * @post After calling this method \SCIP reaches one of the following stages depending on if and when the solution
184  * process was interrupted:
185  * - \ref SCIP_STAGE_PRESOLVING if the solution process was interrupted during presolving
186  * - \ref SCIP_STAGE_SOLVING if the solution process was interrupted during the tree search
187  * - \ref SCIP_STAGE_SOLVED if the solving process was not interrupted
188  *
189  * See \ref SCIP_Stage "SCIP_STAGE" for a complete list of all possible solving stages.
190  */
191 SCIP_EXPORT
193  SCIP* scip /**< SCIP data structure */
194  );
195 
196 /** frees branch and bound tree and all solution process data; statistics, presolving data and transformed problem is
197  * preserved
198  *
199  * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
200  * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
201  *
202  * @pre This method can be called if @p scip is in one of the following stages:
203  * - \ref SCIP_STAGE_INIT
204  * - \ref SCIP_STAGE_PROBLEM
205  * - \ref SCIP_STAGE_TRANSFORMED
206  * - \ref SCIP_STAGE_PRESOLVING
207  * - \ref SCIP_STAGE_PRESOLVED
208  * - \ref SCIP_STAGE_SOLVING
209  * - \ref SCIP_STAGE_SOLVED
210  *
211  * @post If this method is called in \SCIP stage \ref SCIP_STAGE_INIT or \ref SCIP_STAGE_PROBLEM, the stage of
212  * \SCIP is not changed; otherwise, the \SCIP stage is changed to \ref SCIP_STAGE_TRANSFORMED
213  *
214  * See \ref SCIP_Stage "SCIP_STAGE" for a complete list of all possible solving stages.
215  */
216 SCIP_EXPORT
218  SCIP* scip, /**< SCIP data structure */
219  SCIP_Bool restart /**< should certain data be preserved for improved restarting? */
220  );
221 
222 /** frees all solution process data including presolving and transformed problem, only original problem is kept
223  *
224  * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
225  * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
226  *
227  * @pre This method can be called if @p scip is in one of the following stages:
228  * - \ref SCIP_STAGE_INIT
229  * - \ref SCIP_STAGE_PROBLEM
230  * - \ref SCIP_STAGE_TRANSFORMED
231  * - \ref SCIP_STAGE_PRESOLVING
232  * - \ref SCIP_STAGE_PRESOLVED
233  * - \ref SCIP_STAGE_SOLVING
234  * - \ref SCIP_STAGE_SOLVED
235  *
236  * @post After calling this method \SCIP reaches one of the following stages:
237  * - \ref SCIP_STAGE_INIT if the method was called from \SCIP stage \ref SCIP_STAGE_INIT
238  * - \ref SCIP_STAGE_PROBLEM if the method was called from any other of the allowed stages
239  *
240  * See \ref SCIP_Stage "SCIP_STAGE" for a complete list of all possible solving stages.
241  */
242 SCIP_EXPORT
244  SCIP* scip /**< SCIP data structure */
245  );
246 
247 /** informs \SCIP that the solving process should be interrupted as soon as possible (e.g., after the current node has
248  * been solved)
249  *
250  * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
251  * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
252  *
253  * @pre This method can be called if @p scip is in one of the following stages:
254  * - \ref SCIP_STAGE_PROBLEM
255  * - \ref SCIP_STAGE_TRANSFORMING
256  * - \ref SCIP_STAGE_TRANSFORMED
257  * - \ref SCIP_STAGE_INITPRESOLVE
258  * - \ref SCIP_STAGE_PRESOLVING
259  * - \ref SCIP_STAGE_EXITPRESOLVE
260  * - \ref SCIP_STAGE_PRESOLVED
261  * - \ref SCIP_STAGE_SOLVING
262  * - \ref SCIP_STAGE_SOLVED
263  * - \ref SCIP_STAGE_EXITSOLVE
264  * - \ref SCIP_STAGE_FREETRANS
265  *
266  * @note the \SCIP stage does not get changed
267  */
268 SCIP_EXPORT
270  SCIP* scip /**< SCIP data structure */
271  );
272 
273 /** indicates whether \SCIP has been informed that the solving process should be interrupted as soon as possible
274  *
275  * This function returns whether SCIPinterruptSolve() has been called, which is different from SCIPinterrupted(),
276  * which returns whether a SIGINT signal has been received by the SCIP signal handler.
277  *
278  * @pre This method can be called if @p scip is in one of the following stages:
279  * - \ref SCIP_STAGE_PROBLEM
280  * - \ref SCIP_STAGE_TRANSFORMING
281  * - \ref SCIP_STAGE_TRANSFORMED
282  * - \ref SCIP_STAGE_INITPRESOLVE
283  * - \ref SCIP_STAGE_PRESOLVING
284  * - \ref SCIP_STAGE_EXITPRESOLVE
285  * - \ref SCIP_STAGE_PRESOLVED
286  * - \ref SCIP_STAGE_SOLVING
287  * - \ref SCIP_STAGE_SOLVED
288  * - \ref SCIP_STAGE_EXITSOLVE
289  * - \ref SCIP_STAGE_FREETRANS
290  *
291  * @note the \SCIP stage does not get changed
292  */
293 SCIP_EXPORT
295  SCIP* scip /**< SCIP data structure */
296  );
297 
298 /** informs SCIP that the solving process should be restarted as soon as possible (e.g., after the current node has
299  * been solved)
300  *
301  * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
302  * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
303  *
304  * @pre This method can be called if @p scip is in one of the following stages:
305  * - \ref SCIP_STAGE_INITPRESOLVE
306  * - \ref SCIP_STAGE_PRESOLVING
307  * - \ref SCIP_STAGE_EXITPRESOLVE
308  * - \ref SCIP_STAGE_SOLVING
309  *
310  * @note the \SCIP stage does not get changed
311  */
312 SCIP_EXPORT
314  SCIP* scip /**< SCIP data structure */
315  );
316 
317 /** returns whether we are in the restarting phase
318  *
319  * @return TRUE, if we are in the restarting phase; FALSE, otherwise
320  *
321  * @pre This method can be called if @p scip is in one of the following stages:
322  * - \ref SCIP_STAGE_INITPRESOLVE
323  * - \ref SCIP_STAGE_PRESOLVING
324  * - \ref SCIP_STAGE_EXITPRESOLVE
325  * - \ref SCIP_STAGE_PRESOLVED
326  * - \ref SCIP_STAGE_INITSOLVE
327  * - \ref SCIP_STAGE_SOLVING
328  * - \ref SCIP_STAGE_SOLVED
329  * - \ref SCIP_STAGE_EXITSOLVE
330  * - \ref SCIP_STAGE_FREETRANS
331  */
332 SCIP_EXPORT
334  SCIP* scip /**< SCIP data structure */
335  );
336 
337 /**@} */
338 
339 /**@addtogroup PublicReoptimizationMethods
340  *
341  * @{
342  */
343 
344 /** frees branch and bound tree and all solution process data; statistics, presolving data and transformed problem is
345  * preserved
346  *
347  * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
348  * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
349  *
350  * @pre This method can be called if @p scip is in one of the following stages:
351  * - \ref SCIP_STAGE_INIT
352  * - \ref SCIP_STAGE_PROBLEM
353  * - \ref SCIP_STAGE_TRANSFORMED
354  * - \ref SCIP_STAGE_PRESOLVING
355  * - \ref SCIP_STAGE_PRESOLVED
356  * - \ref SCIP_STAGE_SOLVING
357  * - \ref SCIP_STAGE_SOLVED
358  *
359  * @post If this method is called in \SCIP stage \ref SCIP_STAGE_INIT or \ref SCIP_STAGE_PROBLEM, the stage of
360  * \SCIP is not changed; otherwise, the \SCIP stage is changed to \ref SCIP_STAGE_PRESOLVED.
361  *
362  * See \ref SCIP_Stage "SCIP_STAGE" for a complete list of all possible solving stages.
363  */
364 SCIP_EXPORT
366  SCIP* scip /**< SCIP data structure */
367  );
368 
369 /** include specific heuristics and branching rules for reoptimization
370  *
371  * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
372  * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
373  *
374  * @pre This method can be called if @p scip is in one of the following stages:
375  * - \ref SCIP_STAGE_PROBLEM
376  */
377 SCIP_EXPORT
379  SCIP* scip, /**< SCIP data structure */
380  SCIP_Bool enable /**< enable reoptimization (TRUE) or disable it (FALSE) */
381  );
382 
383 /** returns whether reoptimization is enabled or not */
384 SCIP_EXPORT
386  SCIP* scip /**< SCIP data structure */
387  );
388 
389 /** returns the stored solutions corresponding to a given run */
390 SCIP_EXPORT
392  SCIP* scip, /**< SCIP data structue */
393  int run, /**< number of the run */
394  SCIP_SOL** sols, /**< array to store solutions */
395  int allocmem, /**< allocated size of the array */
396  int* nsols /**< number of solutions */
397  );
398 
399 /** mark all stored solutions as not updated */
400 SCIP_EXPORT
402  SCIP* scip /**< SCIP data structure */
403  );
404 
405 /** check if the reoptimization process should be restarted
406  *
407  * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
408  * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
409  *
410  * @pre This method can be called if @p scip is in one of the following stages:
411  * - \ref SCIP_STAGE_TRANSFORMED
412  * - \ref SCIP_STAGE_SOLVING
413  */
414 SCIP_EXPORT
416  SCIP* scip, /**< SCIP data structure */
417  SCIP_NODE* node, /**< current node of the branch and bound tree (or NULL) */
418  SCIP_Bool* restart /**< pointer to store of the reoptimitation process should be restarted */
419  );
420 
421 /** save bound change based on dual information in the reoptimization tree
422  *
423  * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
424  * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
425  *
426  * @pre This method can be called if @p scip is in one of the following stages:
427  * - \ref SCIP_STAGE_SOLVING
428  * - \ref SCIP_STAGE_SOLVED
429  */
430 SCIP_EXPORT
432  SCIP* scip, /**< SCIP data structure */
433  SCIP_NODE* node, /**< node of the search tree */
434  SCIP_VAR* var, /**< variable whose bound changed */
435  SCIP_Real newbound, /**< new bound of the variable */
436  SCIP_Real oldbound /**< old bound of the variable */
437  );
438 
439 /** returns the optimal solution of the last iteration or NULL of none exists */
440 SCIP_EXPORT
442  SCIP* scip /**< SCIP data structure */
443  );
444 
445 /** returns the objective coefficent of a given variable in a previous iteration
446  *
447  * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
448  * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
449  *
450  * @pre This method can be called if @p scip is in one of the following stages:
451  * - \ref SCIP_STAGE_PRESOLVING
452  * - \ref SCIP_STAGE_SOLVING
453  */
454 SCIP_EXPORT
456  SCIP* scip, /**< SCIP data structure */
457  SCIP_VAR* var, /**< variable */
458  int run, /**< number of the run */
459  SCIP_Real* objcoef /**< pointer to store the objective coefficient */
460  );
461 
462 /**@} */
463 
464 #ifdef __cplusplus
465 }
466 #endif
467 
468 #endif
SCIP_RETCODE SCIPenableReoptimization(SCIP *scip, SCIP_Bool enable)
Definition: scip_solve.c:3168
SCIP_RETCODE SCIPcheckReoptRestart(SCIP *scip, SCIP_NODE *node, SCIP_Bool *restart)
Definition: scip_solve.c:3681
SCIP_RETCODE SCIPgetReoptSolsRun(SCIP *scip, int run, SCIP_SOL **sols, int allocmem, int *nsols)
Definition: scip_solve.c:3631
enum SCIP_Retcode SCIP_RETCODE
Definition: type_retcode.h:63
type definitions for return codes for SCIP methods
SCIP_Bool SCIPisReoptEnabled(SCIP *scip)
Definition: scip_solve.c:3621
void SCIPresetReoptSolMarks(SCIP *scip)
Definition: scip_solve.c:3657
SCIP_RETCODE SCIPsolve(SCIP *scip)
Definition: scip_solve.c:2624
SCIP_SOL * SCIPgetReoptLastOptSol(SCIP *scip)
Definition: scip_solve.c:3256
type definitions for SCIP&#39;s main datastructure
SCIP_RETCODE SCIPpresolve(SCIP *scip)
Definition: scip_solve.c:2454
type definitions for problem variables
SCIP_RETCODE SCIPfreeTransform(SCIP *scip)
Definition: scip_solve.c:3469
#define SCIP_Bool
Definition: def.h:93
SCIP_RETCODE SCIPaddReoptDualBndchg(SCIP *scip, SCIP_NODE *node, SCIP_VAR *var, SCIP_Real newbound, SCIP_Real oldbound)
Definition: scip_solve.c:3238
type definitions for branch and bound tree
type definitions for storing primal CIP solutions
SCIP_RETCODE SCIPsolveConcurrent(SCIP *scip)
Definition: scip_solve.c:2985
SCIP_RETCODE SCIPrestartSolve(SCIP *scip)
Definition: scip_solve.c:3608
#define SCIP_Real
Definition: def.h:186
SCIP_RETCODE SCIPsolveParallel(SCIP *scip)
Definition: scip_solve.c:2955
SCIP_RETCODE SCIPtransformProb(SCIP *scip)
Definition: scip_solve.c:367
SCIP_RETCODE SCIPgetReoptOldObjCoef(SCIP *scip, SCIP_VAR *var, int run, SCIP_Real *objcoef)
Definition: scip_solve.c:3283
SCIP_RETCODE SCIPinterruptSolve(SCIP *scip)
Definition: scip_solve.c:3553
common defines and data types used in all packages of SCIP
SCIP_RETCODE SCIPfreeReoptSolve(SCIP *scip)
Definition: scip_solve.c:3406
SCIP_RETCODE SCIPfreeSolve(SCIP *scip, SCIP_Bool restart)
Definition: scip_solve.c:3339
SCIP_Bool SCIPisInRestart(SCIP *scip)
Definition: scip_solve.c:3714
SCIP_Bool SCIPisSolveInterrupted(SCIP *scip)
Definition: scip_solve.c:3585