Scippy

SCIP

Solving Constraint Integer Programs

cons_setppc.h
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1/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
2/* */
3/* This file is part of the program and library */
4/* SCIP --- Solving Constraint Integer Programs */
5/* */
6/* Copyright (c) 2002-2025 Zuse Institute Berlin (ZIB) */
7/* */
8/* Licensed under the Apache License, Version 2.0 (the "License"); */
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23/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
24
25/**@file cons_setppc.h
26 * @ingroup CONSHDLRS
27 * @brief Constraint handler for the set partitioning / packing / covering constraints \f$1^T x\ \{=, \le, \ge\}\ 1\f$.
28 * @author Tobias Achterberg
29 * @author Michael Winkler
30 *
31 */
32
33/*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
34
35#ifndef __SCIP_CONS_SETPPC_H__
36#define __SCIP_CONS_SETPPC_H__
37
38
39#include "scip/def.h"
40#include "scip/type_cons.h"
41#include "scip/type_lp.h"
42#include "scip/type_retcode.h"
43#include "scip/type_scip.h"
44#include "scip/type_var.h"
45
46#ifdef __cplusplus
47extern "C" {
48#endif
49
50
51/** creates the handler for set partitioning / packing / covering constraints and includes it in SCIP
52 *
53 * @ingroup ConshdlrIncludes
54 * */
55SCIP_EXPORT
56SCIP_RETCODE SCIPincludeConshdlrSetppc(
57 SCIP* scip /**< SCIP data structure */
58 );
59
60/**@addtogroup CONSHDLRS
61 *
62 * @{
63 *
64 * @name Set Packing/Partitioning/Covering Constraints
65 *
66 * @{
67 *
68 * This constraint handler handles three special classes of linear constraints, namely
69 * set partitioning, set packing, and set covering constraints.
70 * For a set of binary variables \f$x_i, i=1,\dots,n\f$, a set partitioning constraint has the form
71 * \f[
72 * \sum_{i=1}^n x_i = 1,
73 * \f]
74 * a set packing constraint has the form
75 * \f[
76 * \sum_{i=1}^n x_i \le 1,
77 * \f]
78 * and a set covering constraint has the form
79 * \f[
80 * \sum_{i=1}^n x_i \ge 1.
81 * \f]
82 */
83
84/** type of setppc constraint: set partitioning, set packing, or set covering */
85enum SCIP_SetppcType
86{
87 SCIP_SETPPCTYPE_PARTITIONING = 0, /**< constraint is a set partitioning constraint: sum(x) == 1 */
88 SCIP_SETPPCTYPE_PACKING = 1, /**< constraint is a set packing constraint: sum(x) <= 1 */
89 SCIP_SETPPCTYPE_COVERING = 2 /**< constraint is a set covering constraint: sum(x) >= 1 */
90};
91typedef enum SCIP_SetppcType SCIP_SETPPCTYPE;
92
93/** creates and captures a set partitioning constraint
94 *
95 * @note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()
96 */
97SCIP_EXPORT
98SCIP_RETCODE SCIPcreateConsSetpart(
99 SCIP* scip, /**< SCIP data structure */
100 SCIP_CONS** cons, /**< pointer to hold the created constraint */
101 const char* name, /**< name of constraint */
102 int nvars, /**< number of variables in the constraint */
103 SCIP_VAR** vars, /**< array with variables of constraint entries */
104 SCIP_Bool initial, /**< should the LP relaxation of constraint be in the initial LP?
105 * Usually set to TRUE. Set to FALSE for 'lazy constraints'. */
106 SCIP_Bool separate, /**< should the constraint be separated during LP processing?
107 * Usually set to TRUE. */
108 SCIP_Bool enforce, /**< should the constraint be enforced during node processing?
109 * TRUE for model constraints, FALSE for additional, redundant constraints. */
110 SCIP_Bool check, /**< should the constraint be checked for feasibility?
111 * TRUE for model constraints, FALSE for additional, redundant constraints. */
112 SCIP_Bool propagate, /**< should the constraint be propagated during node processing?
113 * Usually set to TRUE. */
114 SCIP_Bool local, /**< is constraint only valid locally?
115 * Usually set to FALSE. Has to be set to TRUE, e.g., for branching constraints. */
116 SCIP_Bool modifiable, /**< is constraint modifiable (subject to column generation)?
117 * Usually set to FALSE. In column generation applications, set to TRUE if pricing
118 * adds coefficients to this constraint. */
119 SCIP_Bool dynamic, /**< is constraint subject to aging?
120 * Usually set to FALSE. Set to TRUE for own cuts which
121 * are separated as constraints. */
122 SCIP_Bool removable, /**< should the relaxation be removed from the LP due to aging or cleanup?
123 * Usually set to FALSE. Set to TRUE for 'lazy constraints' and 'user cuts'. */
124 SCIP_Bool stickingatnode /**< should the constraint always be kept at the node where it was added, even
125 * if it may be moved to a more global node?
126 * Usually set to FALSE. Set to TRUE to for constraints that represent node data. */
127 );
128
129/** creates and captures a set partitioning constraint
130 * in its most basic variant, i. e., with all constraint flags set to their default values, which can be set
131 * afterwards using SCIPsetConsFLAGNAME() in scip.h
132 *
133 * @see SCIPcreateConsSetpart() for the default constraint flag configuration
134 *
135 * @note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()
136 */
137SCIP_EXPORT
138SCIP_RETCODE SCIPcreateConsBasicSetpart(
139 SCIP* scip, /**< SCIP data structure */
140 SCIP_CONS** cons, /**< pointer to hold the created constraint */
141 const char* name, /**< name of constraint */
142 int nvars, /**< number of variables in the constraint */
143 SCIP_VAR** vars /**< array with variables of constraint entries */
144 );
145
146/** creates and captures a set packing constraint
147 *
148 * @note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()
149 */
150SCIP_EXPORT
151SCIP_RETCODE SCIPcreateConsSetpack(
152 SCIP* scip, /**< SCIP data structure */
153 SCIP_CONS** cons, /**< pointer to hold the created constraint */
154 const char* name, /**< name of constraint */
155 int nvars, /**< number of variables in the constraint */
156 SCIP_VAR** vars, /**< array with variables of constraint entries */
157 SCIP_Bool initial, /**< should the LP relaxation of constraint be in the initial LP?
158 * Usually set to TRUE. Set to FALSE for 'lazy constraints'. */
159 SCIP_Bool separate, /**< should the constraint be separated during LP processing?
160 * Usually set to TRUE. */
161 SCIP_Bool enforce, /**< should the constraint be enforced during node processing?
162 * TRUE for model constraints, FALSE for additional, redundant constraints. */
163 SCIP_Bool check, /**< should the constraint be checked for feasibility?
164 * TRUE for model constraints, FALSE for additional, redundant constraints. */
165 SCIP_Bool propagate, /**< should the constraint be propagated during node processing?
166 * Usually set to TRUE. */
167 SCIP_Bool local, /**< is constraint only valid locally?
168 * Usually set to FALSE. Has to be set to TRUE, e.g., for branching constraints. */
169 SCIP_Bool modifiable, /**< is constraint modifiable (subject to column generation)?
170 * Usually set to FALSE. In column generation applications, set to TRUE if pricing
171 * adds coefficients to this constraint. */
172 SCIP_Bool dynamic, /**< is constraint subject to aging?
173 * Usually set to FALSE. Set to TRUE for own cuts which
174 * are separated as constraints. */
175 SCIP_Bool removable, /**< should the relaxation be removed from the LP due to aging or cleanup?
176 * Usually set to FALSE. Set to TRUE for 'lazy constraints' and 'user cuts'. */
177 SCIP_Bool stickingatnode /**< should the constraint always be kept at the node where it was added, even
178 * if it may be moved to a more global node?
179 * Usually set to FALSE. Set to TRUE to for constraints that represent node data. */
180 );
181
182/** creates and captures a set packing constraint
183 * in its most basic variant, i. e., with all constraint flags set to their default values, which can be set
184 * afterwards using SCIPsetConsFLAGNAME() in scip.h
185 *
186 * @see SCIPcreateConsSetpack() for the default constraint flag configuration
187 *
188 * @note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()
189 */
190SCIP_EXPORT
191SCIP_RETCODE SCIPcreateConsBasicSetpack(
192 SCIP* scip, /**< SCIP data structure */
193 SCIP_CONS** cons, /**< pointer to hold the created constraint */
194 const char* name, /**< name of constraint */
195 int nvars, /**< number of variables in the constraint */
196 SCIP_VAR** vars /**< array with variables of constraint entries */
197 );
198
199/** creates and captures a set covering constraint
200 *
201 * @note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()
202 */
203SCIP_EXPORT
204SCIP_RETCODE SCIPcreateConsSetcover(
205 SCIP* scip, /**< SCIP data structure */
206 SCIP_CONS** cons, /**< pointer to hold the created constraint */
207 const char* name, /**< name of constraint */
208 int nvars, /**< number of variables in the constraint */
209 SCIP_VAR** vars, /**< array with variables of constraint entries */
210 SCIP_Bool initial, /**< should the LP relaxation of constraint be in the initial LP?
211 * Usually set to TRUE. Set to FALSE for 'lazy constraints'. */
212 SCIP_Bool separate, /**< should the constraint be separated during LP processing?
213 * Usually set to TRUE. */
214 SCIP_Bool enforce, /**< should the constraint be enforced during node processing?
215 * TRUE for model constraints, FALSE for additional, redundant constraints. */
216 SCIP_Bool check, /**< should the constraint be checked for feasibility?
217 * TRUE for model constraints, FALSE for additional, redundant constraints. */
218 SCIP_Bool propagate, /**< should the constraint be propagated during node processing?
219 * Usually set to TRUE. */
220 SCIP_Bool local, /**< is constraint only valid locally?
221 * Usually set to FALSE. Has to be set to TRUE, e.g., for branching constraints. */
222 SCIP_Bool modifiable, /**< is constraint modifiable (subject to column generation)?
223 * Usually set to FALSE. In column generation applications, set to TRUE if pricing
224 * adds coefficients to this constraint. */
225 SCIP_Bool dynamic, /**< is constraint subject to aging?
226 * Usually set to FALSE. Set to TRUE for own cuts which
227 * are separated as constraints. */
228 SCIP_Bool removable, /**< should the relaxation be removed from the LP due to aging or cleanup?
229 * Usually set to FALSE. Set to TRUE for 'lazy constraints' and 'user cuts'. */
230 SCIP_Bool stickingatnode /**< should the constraint always be kept at the node where it was added, even
231 * if it may be moved to a more global node?
232 * Usually set to FALSE. Set to TRUE to for constraints that represent node data. */
233 );
234
235/** creates and captures a set packing constraint
236 * in its most basic variant, i. e., with all constraint flags set to their default values, which can be set
237 * afterwards using SCIPsetConsFLAGNAME() in scip.h
238 *
239 * @see SCIPcreateConsSetpack() for the default constraint flag configuration
240 *
241 * @note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()
242 */
243SCIP_EXPORT
244SCIP_RETCODE SCIPcreateConsBasicSetcover(
245 SCIP* scip, /**< SCIP data structure */
246 SCIP_CONS** cons, /**< pointer to hold the created constraint */
247 const char* name, /**< name of constraint */
248 int nvars, /**< number of variables in the constraint */
249 SCIP_VAR** vars /**< array with variables of constraint entries */
250 );
251
252/** adds coefficient in set partitioning / packing / covering constraint */
253SCIP_EXPORT
254SCIP_RETCODE SCIPaddCoefSetppc(
255 SCIP* scip, /**< SCIP data structure */
256 SCIP_CONS* cons, /**< constraint data */
257 SCIP_VAR* var /**< variable to add to the constraint */
258 );
259
260/** gets number of variables in set partitioning / packing / covering constraint */
261SCIP_EXPORT
262int SCIPgetNVarsSetppc(
263 SCIP* scip, /**< SCIP data structure */
264 SCIP_CONS* cons /**< constraint data */
265 );
266
267/** gets array of variables in set partitioning / packing / covering constraint */
268SCIP_EXPORT
269SCIP_VAR** SCIPgetVarsSetppc(
270 SCIP* scip, /**< SCIP data structure */
271 SCIP_CONS* cons /**< constraint data */
272 );
273
274/** gets type of set partitioning / packing / covering constraint */
275SCIP_EXPORT
276SCIP_SETPPCTYPE SCIPgetTypeSetppc(
277 SCIP* scip, /**< SCIP data structure */
278 SCIP_CONS* cons /**< constraint data */
279 );
280
281/** gets the dual solution of the set partitioning / packing / covering constraint in the current LP */
282SCIP_EXPORT
283SCIP_Real SCIPgetDualsolSetppc(
284 SCIP* scip, /**< SCIP data structure */
285 SCIP_CONS* cons /**< constraint data */
286 );
287
288/** gets the dual Farkas value of the set partitioning / packing / covering constraint in the current infeasible LP */
289SCIP_EXPORT
290SCIP_Real SCIPgetDualfarkasSetppc(
291 SCIP* scip, /**< SCIP data structure */
292 SCIP_CONS* cons /**< constraint data */
293 );
294
295/** returns the linear relaxation of the given set partitioning / packing / covering constraint; may return NULL if no
296 * LP row was yet created; the user must not modify the row!
297 */
298SCIP_EXPORT
299SCIP_ROW* SCIPgetRowSetppc(
300 SCIP* scip, /**< SCIP data structure */
301 SCIP_CONS* cons /**< constraint data */
302 );
303
304/** creates and returns the row of the given set partitioning / packing / covering constraint */
305SCIP_EXPORT
306SCIP_RETCODE SCIPcreateRowSetppc(
307 SCIP* scip, /**< SCIP data structure */
308 SCIP_CONS* cons /**< constraint data */
309 );
310
311/** returns current number of variables fixed to one in the constraint */
312SCIP_EXPORT
313int SCIPgetNFixedonesSetppc(
314 SCIP* scip, /**< SCIP data structure */
315 SCIP_CONS* cons /**< constraint data */
316 );
317
318/** returns current number of variables fixed to zero in the constraint */
319SCIP_EXPORT
320int SCIPgetNFixedzerosSetppc(
321 SCIP* scip, /**< SCIP data structure */
322 SCIP_CONS* cons /**< constraint data */
323 );
324
325/** cleans up (multi-)aggregations and fixings from setppc constraints */
326SCIP_EXPORT
327SCIP_RETCODE SCIPcleanupConssSetppc(
328 SCIP* scip, /**< SCIP data structure */
329 SCIP_Bool onlychecked, /**< should only checked constraints be cleaned up? */
330 SCIP_Bool* infeasible, /**< pointer to return whether problem was detected to be infeasible */
331 int* naddconss, /**< pointer to count number of added (linear) constraints */
332 int* ndelconss, /**< pointer to count number of deleted (setppc) constraints */
333 int* nchgcoefs, /**< pointer to count number of changed coefficients */
334 int* nfixedvars /**< pointer to count number of fixed variables */
335 );
336
337/** @} */
338
339/** @} */
340
341#ifdef __cplusplus
342}
343#endif
344
345#endif
def.h
common defines and data types used in all packages of SCIP
SCIP_Bool
#define SCIP_Bool
Definition: def.h:91
SCIP_Real
#define SCIP_Real
Definition: def.h:156
SCIPcleanupConssSetppc
SCIP_RETCODE SCIPcleanupConssSetppc(SCIP *scip, SCIP_Bool onlychecked, SCIP_Bool *infeasible, int *naddconss, int *ndelconss, int *nchgcoefs, int *nfixedvars)
Definition: cons_setppc.c:9839
SCIPcreateConsBasicSetpart
SCIP_RETCODE SCIPcreateConsBasicSetpart(SCIP *scip, SCIP_CONS **cons, const char *name, int nvars, SCIP_VAR **vars)
Definition: cons_setppc.c:9442
SCIPgetNFixedzerosSetppc
int SCIPgetNFixedzerosSetppc(SCIP *scip, SCIP_CONS *cons)
Definition: cons_setppc.c:9816
SCIPgetRowSetppc
SCIP_ROW * SCIPgetRowSetppc(SCIP *scip, SCIP_CONS *cons)
Definition: cons_setppc.c:9718
SCIPgetNVarsSetppc
int SCIPgetNVarsSetppc(SCIP *scip, SCIP_CONS *cons)
Definition: cons_setppc.c:9596
SCIPcreateConsSetpack
SCIP_RETCODE SCIPcreateConsSetpack(SCIP *scip, SCIP_CONS **cons, const char *name, int nvars, SCIP_VAR **vars, SCIP_Bool initial, SCIP_Bool separate, SCIP_Bool enforce, SCIP_Bool check, SCIP_Bool propagate, SCIP_Bool local, SCIP_Bool modifiable, SCIP_Bool dynamic, SCIP_Bool removable, SCIP_Bool stickingatnode)
Definition: cons_setppc.c:9460
SCIPgetVarsSetppc
SCIP_VAR ** SCIPgetVarsSetppc(SCIP *scip, SCIP_CONS *cons)
Definition: cons_setppc.c:9619
SCIPgetNFixedonesSetppc
int SCIPgetNFixedonesSetppc(SCIP *scip, SCIP_CONS *cons)
Definition: cons_setppc.c:9792
SCIPcreateConsBasicSetcover
SCIP_RETCODE SCIPcreateConsBasicSetcover(SCIP *scip, SCIP_CONS **cons, const char *name, int nvars, SCIP_VAR **vars)
Definition: cons_setppc.c:9558
SCIPaddCoefSetppc
SCIP_RETCODE SCIPaddCoefSetppc(SCIP *scip, SCIP_CONS *cons, SCIP_VAR *var)
Definition: cons_setppc.c:9573
SCIP_SETPPCTYPE
enum SCIP_SetppcType SCIP_SETPPCTYPE
Definition: cons_setppc.h:91
SCIPgetTypeSetppc
SCIP_SETPPCTYPE SCIPgetTypeSetppc(SCIP *scip, SCIP_CONS *cons)
Definition: cons_setppc.c:9642
SCIPcreateConsSetpart
SCIP_RETCODE SCIPcreateConsSetpart(SCIP *scip, SCIP_CONS **cons, const char *name, int nvars, SCIP_VAR **vars, SCIP_Bool initial, SCIP_Bool separate, SCIP_Bool enforce, SCIP_Bool check, SCIP_Bool propagate, SCIP_Bool local, SCIP_Bool modifiable, SCIP_Bool dynamic, SCIP_Bool removable, SCIP_Bool stickingatnode)
Definition: cons_setppc.c:9402
SCIP_SetppcType
SCIP_SetppcType
Definition: cons_setppc.h:86
SCIPcreateConsSetcover
SCIP_RETCODE SCIPcreateConsSetcover(SCIP *scip, SCIP_CONS **cons, const char *name, int nvars, SCIP_VAR **vars, SCIP_Bool initial, SCIP_Bool separate, SCIP_Bool enforce, SCIP_Bool check, SCIP_Bool propagate, SCIP_Bool local, SCIP_Bool modifiable, SCIP_Bool dynamic, SCIP_Bool removable, SCIP_Bool stickingatnode)
Definition: cons_setppc.c:9518
SCIPgetDualsolSetppc
SCIP_Real SCIPgetDualsolSetppc(SCIP *scip, SCIP_CONS *cons)
Definition: cons_setppc.c:9664
SCIPcreateConsBasicSetpack
SCIP_RETCODE SCIPcreateConsBasicSetpack(SCIP *scip, SCIP_CONS **cons, const char *name, int nvars, SCIP_VAR **vars)
Definition: cons_setppc.c:9500
SCIPcreateRowSetppc
SCIP_RETCODE SCIPcreateRowSetppc(SCIP *scip, SCIP_CONS *cons)
Definition: cons_setppc.c:9741
SCIPgetDualfarkasSetppc
SCIP_Real SCIPgetDualfarkasSetppc(SCIP *scip, SCIP_CONS *cons)
Definition: cons_setppc.c:9690
SCIP_SETPPCTYPE_PARTITIONING
@ SCIP_SETPPCTYPE_PARTITIONING
Definition: cons_setppc.h:87
SCIP_SETPPCTYPE_COVERING
@ SCIP_SETPPCTYPE_COVERING
Definition: cons_setppc.h:89
SCIP_SETPPCTYPE_PACKING
@ SCIP_SETPPCTYPE_PACKING
Definition: cons_setppc.h:88
SCIPincludeConshdlrSetppc
SCIP_RETCODE SCIPincludeConshdlrSetppc(SCIP *scip)
Definition: cons_setppc.c:9299
separate
static SCIP_RETCODE separate(SCIP *scip, SCIP_SEPA *sepa, SCIP_SOL *sol, SCIP_RESULT *result)
Main separation function.
Definition: sepa_flower.c:1221
SCIP_Cons
Definition: struct_cons.h:47
SCIP_Row
Definition: struct_lp.h:205
SCIP_Var
Definition: struct_var.h:262
type_cons.h
type definitions for constraints and constraint handlers
type_lp.h
type definitions for LP management
type_retcode.h
type definitions for return codes for SCIP methods
SCIP_RETCODE
enum SCIP_Retcode SCIP_RETCODE
Definition: type_retcode.h:63
type_scip.h
type definitions for SCIP's main datastructure
type_var.h
type definitions for problem variables