Scippy

    SCIP

    Solving Constraint Integer Programs

    type_cons.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) 2002-2025 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 type_cons.h
    26 * @ingroup TYPEDEFINITIONS
    27 * @brief type definitions for constraints and constraint handlers
    28 * @author Tobias Achterberg
    29 * @author Stefan Heinz
    30 *
    31 * This file defines the interface for constraint handlers implemented in C.
    32 *
    33 * - \ref CONS "Instructions for implementing a constraint handler"
    34 * - \ref CONSHDLRS "List of available constraint handlers"
    35 * - \ref scip::ObjConshdlr "C++ wrapper class"
    36 */
    37
    38/** @defgroup DEFPLUGINS_CONS Default constraint handlers
    39 * @ingroup DEFPLUGINS
    40 * @brief implementation files (.c files) of the default constraint handlers of SCIP
    41 */
    42
    43/*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
    44
    45#ifndef __SCIP_TYPE_CONS_H__
    46#define __SCIP_TYPE_CONS_H__
    47
    48#include "scip/def.h"
    49#include "scip/type_lp.h"
    50#include "scip/type_retcode.h"
    51#include "scip/type_result.h"
    52#include "scip/type_var.h"
    53#include "scip/type_sol.h"
    54#include "scip/type_scip.h"
    55#include "scip/type_timing.h"
    56#include "scip/type_heur.h"
    57
    58#ifdef __cplusplus
    59extern "C" {
    60#endif
    61
    62typedef struct SCIP_Conshdlr SCIP_CONSHDLR; /**< constraint handler for a specific constraint type */
    63typedef struct SCIP_Cons SCIP_CONS; /**< constraint data structure */
    64typedef struct SCIP_ConshdlrData SCIP_CONSHDLRDATA; /**< constraint handler data */
    65typedef struct SCIP_ConsData SCIP_CONSDATA; /**< locally defined constraint type specific data */
    66typedef struct SCIP_ConsSetChg SCIP_CONSSETCHG; /**< tracks additions and removals of the set of active constraints */
    67typedef struct SCIP_LinConsStats SCIP_LINCONSSTATS; /**< linear constraint classification statistics used for MIPLIB */
    68typedef struct SYM_Graph SYM_GRAPH; /**< data to encode a symmetry detection graph */
    69
    70/** linear constraint types recognizable */
    72{
    73 SCIP_LINCONSTYPE_EMPTY = 0, /**< linear constraints with no variables */
    74 SCIP_LINCONSTYPE_FREE = 1, /**< linear constraints with no finite side */
    75 SCIP_LINCONSTYPE_SINGLETON = 2, /**< linear constraints with a single variable */
    76 SCIP_LINCONSTYPE_AGGREGATION = 3, /**< linear constraints of the type \f$ ax + by = c\f$ */
    77 SCIP_LINCONSTYPE_PRECEDENCE = 4, /**< linear constraints of the type \f$ a x - a y \leq b\f$ where \f$x\f$ and \f$y\f$ must have the same type */
    78 SCIP_LINCONSTYPE_VARBOUND = 5, /**< linear constraints of the form \f$ ax + by \leq c \, x \in \{0,1\} \f$ */
    79 SCIP_LINCONSTYPE_SETPARTITION = 6, /**< linear constraints of the form \f$ \sum x_i = 1\, x_i \in \{0,1\} \forall i \f$ */
    80 SCIP_LINCONSTYPE_SETPACKING = 7, /**< linear constraints of the form \f$ \sum x_i \leq 1\, x_i \in \{0,1\} \forall i \f$ */
    81 SCIP_LINCONSTYPE_SETCOVERING = 8, /**< linear constraints of the form \f$ \sum x_i \geq 1\, x_i \in \{0,1\} \forall i \f$ */
    82 SCIP_LINCONSTYPE_CARDINALITY = 9, /**< linear constraints of the form \f$ \sum x_i = k\, x_i \in \{0,1\} \forall i, \, k\geq 2 \f$ */
    83 SCIP_LINCONSTYPE_INVKNAPSACK = 10, /**< linear constraints of the form \f$ \sum x_i \leq b\, x_i \in \{0,1\} \forall i, \, b\in \mathbb{n} \geq 2 \f$ */
    84 SCIP_LINCONSTYPE_EQKNAPSACK = 11, /**< linear constraints of the form \f$ \sum a_i x_i = b\, x_i \in \{0,1\} \forall i, \, b\in \mathbb{n} \geq 2 \f$ */
    85 SCIP_LINCONSTYPE_BINPACKING = 12, /**< linear constraints of the form \f$ \sum a_i x_i + a x \leq a\, x, x_i \in \{0,1\} \forall i, \, a\in \mathbb{n} \geq 2 \f$ */
    86 SCIP_LINCONSTYPE_KNAPSACK = 13, /**< linear constraints of the form \f$ \sum a_k x_k \leq b\, x_i \in \{0,1\} \forall i, \, b\in \mathbb{n} \geq 2 \f$ */
    87 SCIP_LINCONSTYPE_INTKNAPSACK = 14, /**< linear constraints of the form \f$ \sum a_k x_k \leq b\, x_i \in \mathbb{Z} \forall i, \, b\in \mathbb{n} \f$ */
    88 SCIP_LINCONSTYPE_MIXEDBINARY = 15, /**< linear constraints of the form \f$ \sum a_k x_k + \sum p_j s_j \leq/= b\, x_i \in \{0,1\} \forall i, s_j \in \text{ cont. } \forall j\f$ */
    89 SCIP_LINCONSTYPE_GENERAL = 16 /**< general linear constraints with no special structure */
    90};
    92
    93#define SCIP_NLINCONSTYPES ((int)SCIP_LINCONSTYPE_GENERAL+1)
    94
    95/** copy method for constraint handler plugins (called when SCIP copies plugins)
    96 *
    97 * If the copy process was one to one, the valid pointer can be set to TRUE. Otherwise, this pointer has to be set to
    98 * FALSE. If all problem defining objects (constraint handlers and variable pricers) return valid = TRUE for all
    99 * their copying calls, SCIP assumes that it is an overall one to one copy of the original instance. In this case any
    100 * reductions made in the copied SCIP instance can be transfered to the original SCIP instance. If the valid pointer is
    101 * set to TRUE and it was not a one to one copy, it might happen that optimal solutions are cut off.
    102 *
    103 * input:
    104 * - scip : SCIP main data structure
    105 * - conshdlr : the constraint handler itself
    106 * - valid : was the copying process valid?
    107 */
    108#define SCIP_DECL_CONSHDLRCOPY(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_Bool* valid)
    109
    110/** destructor of constraint handler to free constraint handler data (called when SCIP is exiting)
    111 *
    112 * input:
    113 * - scip : SCIP main data structure
    114 * - conshdlr : the constraint handler itself
    115 */
    116#define SCIP_DECL_CONSFREE(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr)
    117
    118/** initialization method of constraint handler (called after problem was transformed)
    119 *
    120 * input:
    121 * - scip : SCIP main data structure
    122 * - conshdlr : the constraint handler itself
    123 * - conss : array of constraints in transformed problem
    124 * - nconss : number of constraints in transformed problem
    125 */
    126#define SCIP_DECL_CONSINIT(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS** conss, int nconss)
    127
    128/** deinitialization method of constraint handler (called before transformed problem is freed)
    129 *
    130 * input:
    131 * - scip : SCIP main data structure
    132 * - conshdlr : the constraint handler itself
    133 * - conss : array of constraints in transformed problem
    134 * - nconss : number of constraints in transformed problem
    135 */
    136#define SCIP_DECL_CONSEXIT(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS** conss, int nconss)
    137
    138/** presolving initialization method of constraint handler (called when presolving is about to begin)
    139 *
    140 * This method is called when the presolving process is about to begin, even if presolving is turned off.
    141 * The constraint handler may use this call to initialize its data structures.
    142 *
    143 * Necessary modifications that have to be performed even if presolving is turned off should be done here or in the
    144 * presolving deinitialization call (SCIP_DECL_CONSEXITPRE()).
    145 *
    146 * @note Note that the constraint array might contain constraints that were created but not added to the problem.
    147 * Constraints that are not added, i.e., for which SCIPconsIsAdded() returns FALSE, cannot be used for problem
    148 * reductions.
    149 *
    150 * input:
    151 * - scip : SCIP main data structure
    152 * - conshdlr : the constraint handler itself
    153 * - conss : array of constraints in transformed problem
    154 * - nconss : number of constraints in transformed problem
    155 */
    156#define SCIP_DECL_CONSINITPRE(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS** conss, int nconss)
    157
    158/** presolving deinitialization method of constraint handler (called after presolving has been finished)
    159 *
    160 * This method is called after the presolving has been finished, even if presolving is turned off.
    161 * The constraint handler may use this call e.g. to clean up or modify its data structures.
    162 *
    163 * Necessary modifications that have to be performed even if presolving is turned off should be done here or in the
    164 * presolving initialization call (SCIP_DECL_CONSINITPRE()).
    165 *
    166 * Besides necessary modifications and clean up, no time consuming operations should be performed, especially if the
    167 * problem has already been solved. Use the method SCIPgetStatus(), which in this case returns SCIP_STATUS_OPTIMAL,
    168 * SCIP_STATUS_INFEASIBLE, SCIP_STATUS_UNBOUNDED, or SCIP_STATUS_INFORUNBD.
    169 *
    170 * @note Note that the constraint array might contain constraints that were created but not added to the problem.
    171 * Constraints that are not added, i.e., for which SCIPconsIsAdded() returns FALSE, cannot be used for problem
    172 * reductions.
    173 *
    174 * input:
    175 * - scip : SCIP main data structure
    176 * - conshdlr : the constraint handler itself
    177 * - conss : final array of constraints in transformed problem
    178 * - nconss : final number of constraints in transformed problem
    179 */
    180#define SCIP_DECL_CONSEXITPRE(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS** conss, int nconss)
    181
    182/** solving process initialization method of constraint handler (called when branch and bound process is about to begin)
    183 *
    184 * This method is called when the presolving was finished and the branch and bound process is about to begin.
    185 * The constraint handler may use this call to initialize its branch and bound specific data.
    186 *
    187 * Besides necessary modifications and clean up, no time consuming operations should be performed, especially if the
    188 * problem has already been solved. Use the method SCIPgetStatus(), which in this case returns SCIP_STATUS_OPTIMAL,
    189 * SCIP_STATUS_INFEASIBLE, SCIP_STATUS_UNBOUNDED, or SCIP_STATUS_INFORUNBD.
    190 *
    191 * @note Note that the constraint array might contain constraints that were created but not added to the problem.
    192 * Constraints that are not added, i.e., for which SCIPconsIsAdded() returns FALSE, cannot be used for problem
    193 * reductions.
    194 *
    195 * input:
    196 * - scip : SCIP main data structure
    197 * - conshdlr : the constraint handler itself
    198 * - conss : array of constraints of the constraint handler
    199 * - nconss : number of constraints of the constraint handler
    200 */
    201#define SCIP_DECL_CONSINITSOL(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS** conss, int nconss)
    202
    203/** solving process deinitialization method of constraint handler (called before branch and bound process data is freed)
    204 *
    205 * This method is called before the branch and bound process is freed.
    206 * The constraint handler should use this call to clean up its branch and bound data, in particular to release
    207 * all LP rows that he has created or captured.
    208 *
    209 * input:
    210 * - scip : SCIP main data structure
    211 * - conshdlr : the constraint handler itself
    212 * - conss : array of constraints of the constraint handler
    213 * - nconss : number of constraints of the constraint handler
    214 * - restart : was this exit solve call triggered by a restart?
    215 */
    216#define SCIP_DECL_CONSEXITSOL(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS** conss, int nconss, SCIP_Bool restart)
    217
    218/** frees specific constraint data
    219 *
    220 * @warning There may exist unprocessed events. For example, a variable's bound may have been already changed, but the
    221 * corresponding bound change event was not yet processed.
    222 *
    223 * input:
    224 * - scip : SCIP main data structure
    225 * - conshdlr : the constraint handler itself
    226 * - cons : the constraint belonging to the constraint data
    227 * - consdata : pointer to the constraint data to free
    228 */
    229#define SCIP_DECL_CONSDELETE(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS* cons, SCIP_CONSDATA** consdata)
    230
    231/** transforms constraint data into data belonging to the transformed problem
    232 *
    233 * input:
    234 * - scip : SCIP main data structure
    235 * - conshdlr : the constraint handler itself
    236 * - sourcecons : source constraint to transform
    237 * - targetcons : pointer to store created target constraint
    238 */
    239#define SCIP_DECL_CONSTRANS(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS* sourcecons, SCIP_CONS** targetcons)
    240
    241/** LP initialization method of constraint handler (called before the initial LP relaxation at a node is solved)
    242 *
    243 * Puts the LP relaxations of all "initial" constraints into the LP. The method should put a canonic LP relaxation
    244 * of all given constraints to the LP with calls to SCIPaddRow().
    245 *
    246 * @warning It is not guaranteed that the problem is going to be declared infeasible if the infeasible pointer is set
    247 * to TRUE. Therefore, it is recommended that users do not end this method prematurely when an infeasiblity
    248 * is detected.
    249 *
    250 * input:
    251 * - scip : SCIP main data structure
    252 * - conshdlr : the constraint handler itself
    253 * - conss : array of constraints to process
    254 * - nconss : number of constraints to process
    255 *
    256 * output:
    257 * - infeasible : pointer to store whether an infeasibility was detected while building the LP
    258 */
    259#define SCIP_DECL_CONSINITLP(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS** conss, int nconss, SCIP_Bool* infeasible)
    260
    261/** separation method of constraint handler for LP solution
    262 *
    263 * Separates all constraints of the constraint handler. The method is called in the LP solution loop,
    264 * which means that a valid LP solution exists.
    265 *
    266 * The first nusefulconss constraints are the ones, that are identified to likely be violated. The separation
    267 * method should process only the useful constraints in most runs, and only occasionally the remaining
    268 * nconss - nusefulconss constraints.
    269 *
    270 * input:
    271 * - scip : SCIP main data structure
    272 * - conshdlr : the constraint handler itself
    273 * - conss : array of constraints to process
    274 * - nconss : number of constraints to process
    275 * - nusefulconss : number of useful (non-obsolete) constraints to process
    276 * - result : pointer to store the result of the separation call
    277 *
    278 * possible return values for *result (if more than one applies, the first in the list should be used):
    279 * - SCIP_CUTOFF : the node is infeasible in the variable's bounds and can be cut off
    280 * - SCIP_CONSADDED : an additional constraint was generated
    281 * - SCIP_REDUCEDDOM : a variable's domain was reduced
    282 * - SCIP_SEPARATED : a cutting plane was generated
    283 * - SCIP_NEWROUND : a cutting plane was generated and a new separation round should immediately start
    284 * - SCIP_DIDNOTFIND : the separator searched, but did not find domain reductions, cutting planes, or cut constraints
    285 * - SCIP_DIDNOTRUN : the separator was skipped
    286 * - SCIP_DELAYED : the separator was skipped, but should be called again
    287 */
    288#define SCIP_DECL_CONSSEPALP(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS** conss, \
    289 int nconss, int nusefulconss, SCIP_RESULT* result)
    290
    291/** separation method of constraint handler for arbitrary primal solution
    292 *
    293 * Separates all constraints of the constraint handler. The method is called outside the LP solution loop (e.g., by
    294 * a relaxator or a primal heuristic), which means that there is no valid LP solution.
    295 * Instead, the method should produce cuts that separate the given solution.
    296 *
    297 * The first nusefulconss constraints are the ones, that are identified to likely be violated. The separation
    298 * method should process only the useful constraints in most runs, and only occasionally the remaining
    299 * nconss - nusefulconss constraints.
    300 *
    301 * input:
    302 * - scip : SCIP main data structure
    303 * - conshdlr : the constraint handler itself
    304 * - conss : array of constraints to process
    305 * - nconss : number of constraints to process
    306 * - nusefulconss : number of useful (non-obsolete) constraints to process
    307 * - sol : primal solution that should be separated
    308 * - result : pointer to store the result of the separation call
    309 *
    310 * possible return values for *result (if more than one applies, the first in the list should be used):
    311 * - SCIP_CUTOFF : the node is infeasible in the variable's bounds and can be cut off
    312 * - SCIP_CONSADDED : an additional constraint was generated
    313 * - SCIP_REDUCEDDOM : a variable's domain was reduced
    314 * - SCIP_SEPARATED : a cutting plane was generated
    315 * - SCIP_NEWROUND : a cutting plane was generated and a new separation round should immediately start
    316 * - SCIP_DIDNOTFIND : the separator searched, but did not find domain reductions, cutting planes, or cut constraints
    317 * - SCIP_DIDNOTRUN : the separator was skipped
    318 * - SCIP_DELAYED : the separator was skipped, but should be called again
    319 */
    320#define SCIP_DECL_CONSSEPASOL(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS** conss, \
    321 int nconss, int nusefulconss, SCIP_SOL* sol, SCIP_RESULT* result)
    322
    323/** constraint enforcing method of constraint handler for LP solutions
    324 *
    325 * The method is called at the end of the node processing loop for a node where the LP was solved.
    326 * The LP solution has to be checked for feasibility. If possible, an infeasibility should be resolved by
    327 * branching, reducing a variable's domain to exclude the solution or separating the solution with a valid
    328 * cutting plane.
    329 *
    330 * The enforcing methods of the active constraint handlers are called in decreasing order of their enforcing
    331 * priorities until the first constraint handler returned with the value SCIP_CUTOFF, SCIP_SEPARATED,
    332 * SCIP_REDUCEDDOM, SCIP_CONSADDED, or SCIP_BRANCHED.
    333 * The integrality constraint handler has an enforcing priority of zero. A constraint handler which can
    334 * (or wants) to enforce its constraints only for integral solutions should have a negative enforcing priority
    335 * (e.g. the alldiff-constraint can only operate on integral solutions).
    336 * A constraint handler which wants to incorporate its own branching strategy even on non-integral
    337 * solutions must have an enforcing priority greater than zero (e.g. the SOS-constraint incorporates
    338 * SOS-branching on non-integral solutions).
    339 *
    340 * The first nusefulconss constraints are the ones, that are identified to likely be violated. The enforcing
    341 * method should process the useful constraints first. The other nconss - nusefulconss constraints should only
    342 * be enforced, if no violation was found in the useful constraints.
    343 *
    344 * input:
    345 * - scip : SCIP main data structure
    346 * - conshdlr : the constraint handler itself
    347 * - conss : array of constraints to process
    348 * - nconss : number of constraints to process
    349 * - nusefulconss : number of useful (non-obsolete) constraints to process
    350 * - solinfeasible : was the solution already declared infeasible by a constraint handler?
    351 * - result : pointer to store the result of the enforcing call
    352 *
    353 * possible return values for *result (if more than one applies, the first in the list should be used):
    354 * - SCIP_CUTOFF : the node is infeasible in the variable's bounds and can be cut off
    355 * - SCIP_CONSADDED : an additional constraint was generated (added constraints must have initial flag = TRUE)
    356 * - SCIP_REDUCEDDOM : a variable's domain was reduced
    357 * - SCIP_SEPARATED : a cutting plane was generated
    358 * - SCIP_SOLVELP : the LP should be solved again because the LP primal feasibility tolerance has been tightened
    359 * - SCIP_BRANCHED : no changes were made to the problem, but a branching was applied to resolve an infeasibility
    360 * - SCIP_INFEASIBLE : at least one constraint is infeasible, but it was not resolved
    361 * - SCIP_FEASIBLE : all constraints of the handler are feasible
    362 */
    363#define SCIP_DECL_CONSENFOLP(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS** conss, int nconss, int nusefulconss, \
    364 SCIP_Bool solinfeasible, SCIP_RESULT* result)
    365
    366/** constraint enforcing method of constraint handler for relaxation solutions
    367 *
    368 * input:
    369 * - scip : SCIP main data structure
    370 * - sol : relaxation solution
    371 * - conshdlr : the constraint handler itself
    372 * - conss : array of constraints to process
    373 * - nconss : number of constraints to process
    374 * - nusefulconss : number of useful (non-obsolete) constraints to process
    375 * - solinfeasible : was the solution already declared infeasible by a constraint handler?
    376 * - result : pointer to store the result of the enforcing call
    377 *
    378 * possible return values for *result (if more than one applies, the first in the list should be used):
    379 * - SCIP_CUTOFF : the node is infeasible in the variable's bounds and can be cut off
    380 * - SCIP_CONSADDED : an additional constraint was generated (added constraints must have initial flag = TRUE)
    381 * - SCIP_REDUCEDDOM : a variable's domain was reduced
    382 * - SCIP_SEPARATED : a cutting plane was generated
    383 * - SCIP_BRANCHED : no changes were made to the problem, but a branching was applied to resolve an infeasibility
    384 * - SCIP_SOLVELP : at least one constraint is infeasible, and this can only be resolved by solving the LP
    385 * - SCIP_INFEASIBLE : at least one constraint is infeasible, but it was not resolved
    386 * - SCIP_FEASIBLE : all constraints of the handler are feasible
    387 */
    388#define SCIP_DECL_CONSENFORELAX(x) SCIP_RETCODE x (SCIP* scip, SCIP_SOL* sol, SCIP_CONSHDLR* conshdlr, SCIP_CONS** conss, int nconss, int nusefulconss, \
    389 SCIP_Bool solinfeasible, SCIP_RESULT* result)
    390
    391/** constraint enforcing method of constraint handler for pseudo solutions
    392 *
    393 * The method is called at the end of the node processing loop for a node where the LP was not solved.
    394 * The pseudo solution has to be checked for feasibility. If possible, an infeasibility should be resolved by
    395 * branching, reducing a variable's domain to exclude the solution or adding an additional constraint.
    396 * Separation is not possible, since the LP is not processed at the current node. All LP informations like
    397 * LP solution, slack values, or reduced costs are invalid and must not be accessed.
    398 *
    399 * Like in the enforcing method for LP solutions, the enforcing methods of the active constraint handlers are
    400 * called in decreasing order of their enforcing priorities until the first constraint handler returned with
    401 * the value SCIP_CUTOFF, SCIP_REDUCEDDOM, SCIP_CONSADDED, SCIP_BRANCHED, or SCIP_SOLVELP.
    402 *
    403 * The first nusefulconss constraints are the ones, that are identified to likely be violated. The enforcing
    404 * method should process the useful constraints first. The other nconss - nusefulconss constraints should only
    405 * be enforced, if no violation was found in the useful constraints.
    406 *
    407 * If the pseudo solution's objective value is lower than the lower bound of the node, it cannot be feasible
    408 * and the enforcing method may skip it's check and set *result to SCIP_DIDNOTRUN. However, it can also process
    409 * its constraints and return any other possible result code.
    410 *
    411 * input:
    412 * - scip : SCIP main data structure
    413 * - conshdlr : the constraint handler itself
    414 * - conss : array of constraints to process
    415 * - nconss : number of constraints to process
    416 * - nusefulconss : number of useful (non-obsolete) constraints to process
    417 * - solinfeasible : was the solution already declared infeasible by a constraint handler?
    418 * - objinfeasible : is the solution infeasible anyway due to violating lower objective bound?
    419 * - result : pointer to store the result of the enforcing call
    420 *
    421 * possible return values for *result (if more than one applies, the first in the list should be used):
    422 * - SCIP_CUTOFF : the node is infeasible in the variable's bounds and can be cut off
    423 * - SCIP_CONSADDED : an additional constraint was generated
    424 * - SCIP_REDUCEDDOM : a variable's domain was reduced
    425 * - SCIP_BRANCHED : no changes were made to the problem, but a branching was applied to resolve an infeasibility
    426 * - SCIP_SOLVELP : at least one constraint is infeasible, and this can only be resolved by solving the LP
    427 * - SCIP_INFEASIBLE : at least one constraint is infeasible, but it was not resolved
    428 * - SCIP_FEASIBLE : all constraints of the handler are feasible
    429 * - SCIP_DIDNOTRUN : the enforcement was skipped (only possible, if objinfeasible is true)
    430 */
    431#define SCIP_DECL_CONSENFOPS(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS** conss, int nconss, int nusefulconss, \
    432 SCIP_Bool solinfeasible, SCIP_Bool objinfeasible, SCIP_RESULT* result)
    433
    434/** feasibility check method of constraint handler for integral solutions
    435 *
    436 * The given solution has to be checked for feasibility.
    437 *
    438 * The check methods of the active constraint handlers are called in decreasing order of their check
    439 * priorities until the first constraint handler returned with the result SCIP_INFEASIBLE.
    440 * The integrality constraint handler has a check priority of zero. A constraint handler which can
    441 * (or wants) to check its constraints only for integral solutions should have a negative check priority
    442 * (e.g. the alldiff-constraint can only operate on integral solutions).
    443 * A constraint handler which wants to check feasibility even on non-integral solutions must have a
    444 * check priority greater than zero (e.g. if the check is much faster than testing all variables for
    445 * integrality).
    446 *
    447 * In some cases, integrality conditions or rows of the current LP don't have to be checked, because their
    448 * feasibility is already checked or implicitly given. In these cases, 'checkintegrality' or
    449 * 'checklprows' is FALSE.
    450 *
    451 * If the solution is not NULL, SCIP should also be informed about the constraint violation with a call to
    452 * SCIPupdateSolConsViolation() and additionally SCIPupdateSolLPRowViolation() for every row of the constraint's current
    453 * representation in the LP relaxation, if any such rows exist.
    454 * As a convenience method, SCIPupdateSolLPConsViolation() can be used if the constraint
    455 * is represented completely by a set of LP rows, meaning that the current constraint violation is equal to the maximum
    456 * of the contraint violations of the corresponding LP rows.
    457 *
    458 * input:
    459 * - scip : SCIP main data structure
    460 * - conshdlr : the constraint handler itself
    461 * - conss : array of constraints to process
    462 * - nconss : number of constraints to process
    463 * - sol : the solution to check feasibility for
    464 * - checkintegrality: Has integrality to be checked?
    465 * - checklprows : Do constraints represented by rows in the current LP have to be checked?
    466 * - printreason : Should the reason for the violation be printed?
    467 * - completely : Should all violations be checked?
    468 * - result : pointer to store the result of the feasibility checking call
    469 *
    470 * possible return values for *result:
    471 * - SCIP_INFEASIBLE : at least one constraint of the handler is infeasible
    472 * - SCIP_FEASIBLE : all constraints of the handler are feasible
    473 */
    474#define SCIP_DECL_CONSCHECK(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS** conss, int nconss, SCIP_SOL* sol, \
    475 SCIP_Bool checkintegrality, SCIP_Bool checklprows, SCIP_Bool printreason, SCIP_Bool completely, SCIP_RESULT* result)
    476
    477/** domain propagation method of constraint handler
    478 *
    479 * The first nusefulconss constraints are the ones, that are identified to likely be violated. The propagation
    480 * method should process only the useful constraints in most runs, and only occasionally the remaining
    481 * nconss - nusefulconss constraints.
    482 *
    483 * @note if the constraint handler uses dual information in propagation it is nesassary to check via calling
    484 * SCIPallowWeakDualReds and SCIPallowStrongDualReds if dual reductions and propgation with the current cutoff bound, resp.,
    485 * are allowed.
    486 *
    487 * input:
    488 * - scip : SCIP main data structure
    489 * - conshdlr : the constraint handler itself
    490 * - conss : array of constraints to process
    491 * - nconss : number of constraints to process
    492 * - nusefulconss : number of useful (non-obsolete) constraints to process
    493 * - nmarkedconss : number of constraints which are marked to be definitely propagated
    494 * - proptiming : current point in the node solving loop
    495 * - result : pointer to store the result of the propagation call
    496 *
    497 * possible return values for *result:
    498 * - SCIP_CUTOFF : the node is infeasible in the variable's bounds and can be cut off
    499 * - SCIP_REDUCEDDOM : at least one domain reduction was found
    500 * - SCIP_DIDNOTFIND : the propagator searched but did not find any domain reductions
    501 * - SCIP_DIDNOTRUN : the propagator was skipped
    502 * - SCIP_DELAYED : the propagator was skipped, but should be called again
    503 * - SCIP_DELAYNODE : the current node should be postponed (return value only valid for BEFORELP propagation)
    504 */
    505#define SCIP_DECL_CONSPROP(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS** conss, int nconss, int nusefulconss, \
    506 int nmarkedconss, SCIP_PROPTIMING proptiming, SCIP_RESULT* result)
    507
    508/** presolving method of constraint handler
    509 *
    510 * The presolver should go through the variables and constraints and tighten the domains or
    511 * constraints. Each tightening should increase the given total number of changes.
    512 *
    513 * input:
    514 * - scip : SCIP main data structure
    515 * - conshdlr : the constraint handler itself
    516 * - conss : array of constraints to process
    517 * - nconss : number of constraints to process
    518 * - nrounds : number of presolving rounds already done
    519 * - presoltiming : current presolving timing
    520 * - nnewfixedvars : number of variables fixed since the last call to the presolving method
    521 * - nnewaggrvars : number of variables aggregated since the last call to the presolving method
    522 * - nnewchgvartypes : number of variable type changes since the last call to the presolving method
    523 * - nnewchgbds : number of variable bounds tightened since the last call to the presolving method
    524 * - nnewholes : number of domain holes added since the last call to the presolving method
    525 * - nnewdelconss : number of deleted constraints since the last call to the presolving method
    526 * - nnewaddconss : number of added constraints since the last call to the presolving method
    527 * - nnewupgdconss : number of upgraded constraints since the last call to the presolving method
    528 * - nnewchgcoefs : number of changed coefficients since the last call to the presolving method
    529 * - nnewchgsides : number of changed left or right hand sides since the last call to the presolving method
    530 *
    531 * @note the counters state the changes since the last call including the changes of this presolving method during its
    532 * call
    533 *
    534 * @note if the constraint handler performs dual presolving it is nesassary to check via calling SCIPallowWeakDualReds
    535 * and SCIPallowStrongDualReds if dual reductions are allowed.
    536 *
    537 * input/output:
    538 * - nfixedvars : pointer to count total number of variables fixed of all presolvers
    539 * - naggrvars : pointer to count total number of variables aggregated of all presolvers
    540 * - nchgvartypes : pointer to count total number of variable type changes of all presolvers
    541 * - nchgbds : pointer to count total number of variable bounds tightened of all presolvers
    542 * - naddholes : pointer to count total number of domain holes added of all presolvers
    543 * - ndelconss : pointer to count total number of deleted constraints of all presolvers
    544 * - naddconss : pointer to count total number of added constraints of all presolvers
    545 * - nupgdconss : pointer to count total number of upgraded constraints of all presolvers
    546 * - nchgcoefs : pointer to count total number of changed coefficients of all presolvers
    547 * - nchgsides : pointer to count total number of changed left/right hand sides of all presolvers
    548 *
    549 * output:
    550 * - result : pointer to store the result of the presolving call
    551 *
    552 * possible return values for *result:
    553 * - SCIP_UNBOUNDED : at least one variable is not bounded by any constraint in obj. direction -> problem is unbounded
    554 * - SCIP_CUTOFF : at least one constraint is infeasible in the variable's bounds -> problem is infeasible
    555 * - SCIP_SUCCESS : the presolving method found a reduction
    556 * - SCIP_DIDNOTFIND : the presolving method searched, but did not find a presolving change
    557 * - SCIP_DIDNOTRUN : the presolving method was skipped
    558 * - SCIP_DELAYED : the presolving method was skipped, but should be called again
    559 */
    560#define SCIP_DECL_CONSPRESOL(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS** conss, int nconss, int nrounds, \
    561 SCIP_PRESOLTIMING presoltiming, int nnewfixedvars, int nnewaggrvars, int nnewchgvartypes, int nnewchgbds, int nnewholes, \
    562 int nnewdelconss, int nnewaddconss, int nnewupgdconss, int nnewchgcoefs, int nnewchgsides, \
    563 int* nfixedvars, int* naggrvars, int* nchgvartypes, int* nchgbds, int* naddholes, \
    564 int* ndelconss, int* naddconss, int* nupgdconss, int* nchgcoefs, int* nchgsides, SCIP_RESULT* result)
    565
    566/** propagation conflict resolving method of constraint handler
    567 *
    568 * This method is called during conflict analysis. If the constraint handler wants to support conflict analysis,
    569 * it should call SCIPinferVarLbCons() or SCIPinferVarUbCons() in domain propagation instead of SCIPchgVarLb() or
    570 * SCIPchgVarUb() in order to deduce bound changes on variables.
    571 * In the SCIPinferVarLbCons() and SCIPinferVarUbCons() calls, the handler provides the constraint, that deduced the
    572 * variable's bound change, and an integer value "inferinfo" that can be arbitrarily chosen.
    573 * The propagation conflict resolving method can then be implemented, to provide a "reason" for the bound
    574 * changes, i.e., the bounds of variables at the time of the propagation, that forced the constraint to set the
    575 * conflict variable's bound to its current value. It can use the "inferinfo" tag to identify its own propagation
    576 * rule and thus identify the "reason" bounds. The bounds that form the reason of the assignment must then be provided
    577 * by calls to SCIPaddConflictLb(), SCIPaddConflictUb(), SCIPaddConflictBd(), SCIPaddConflictRelaxedLb(),
    578 * SCIPaddConflictRelaxedUb(), SCIPaddConflictRelaxedBd(), and/or SCIPaddConflictBinvar() in the propagation conflict
    579 * resolving method.
    580 *
    581 * For example, the logicor constraint c = "x or y or z" fixes variable z to TRUE (i.e. changes the lower bound of z
    582 * to 1.0), if both, x and y, are assigned to FALSE (i.e. if the upper bounds of these variables are 0.0). It uses
    583 * SCIPinferVarLbCons(scip, z, 1.0, c, 0) to apply this assignment (an inference information tag is not needed by the
    584 * constraint handler and is set to 0).
    585 * In the conflict analysis, the constraint handler may be asked to resolve the lower bound change on z with
    586 * constraint c, that was applied at a time given by a bound change index "bdchgidx".
    587 * With a call to SCIPgetVarLbAtIndex(scip, z, bdchgidx, TRUE), the handler can find out, that the lower bound of
    588 * variable z was set to 1.0 at the given point of time, and should call SCIPaddConflictUb(scip, x, bdchgidx) and
    589 * SCIPaddConflictUb(scip, y, bdchgidx) to tell SCIP, that the upper bounds of x and y at this point of time were
    590 * the reason for the deduction of the lower bound of z.
    591 *
    592 * input:
    593 * - scip : SCIP main data structure
    594 * - conshdlr : the constraint handler itself
    595 * - cons : the constraint that deduced the bound change of the conflict variable
    596 * - infervar : the conflict variable whose bound change has to be resolved
    597 * - inferinfo : the user information passed to the corresponding SCIPinferVarLbCons() or SCIPinferVarUbCons() call
    598 * - boundtype : the type of the changed bound (lower or upper bound)
    599 * - bdchgidx : the index of the bound change, representing the point of time where the change took place
    600 * - relaxedbd : the relaxed bound which is sufficient to be explained
    601 *
    602 * output:
    603 * - result : pointer to store the result of the propagation conflict resolving call
    604 *
    605 * possible return values for *result:
    606 * - SCIP_SUCCESS : the conflicting bound change has been successfully resolved by adding all reason bounds
    607 * - SCIP_DIDNOTFIND : the conflicting bound change could not be resolved and has to be put into the conflict set
    608 *
    609 * @note it is sufficient to explain/resolve the relaxed bound
    610 */
    611#define SCIP_DECL_CONSRESPROP(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS* cons, \
    612 SCIP_VAR* infervar, int inferinfo, SCIP_BOUNDTYPE boundtype, SCIP_BDCHGIDX* bdchgidx, SCIP_Real relaxedbd, \
    613 SCIP_RESULT* result)
    614
    615/** variable rounding lock method of constraint handler
    616 *
    617 * This method is called, after a constraint is added or removed from the transformed problem.
    618 * It should update the rounding locks of the given type of all associated variables with calls to
    619 * SCIPaddVarLocksType(), depending on the way, the variable is involved in the constraint:
    620 * - If the constraint may get violated by decreasing the value of a variable, it should call
    621 * SCIPaddVarLocksType(scip, var, locktype, nlockspos, nlocksneg), saying that rounding down is
    622 * potentially rendering the (positive) constraint infeasible and rounding up is potentially rendering the
    623 * negation of the constraint infeasible.
    624 * - If the constraint may get violated by increasing the value of a variable, it should call
    625 * SCIPaddVarLocksType(scip, var, locktype, nlocksneg, nlockspos), saying that rounding up is
    626 * potentially rendering the constraint's negation infeasible and rounding up is potentially rendering the
    627 * constraint itself infeasible.
    628 * - If the constraint may get violated by changing the variable in any direction, it should call
    629 * SCIPaddVarLocksType(scip, var, locktype, nlockspos + nlocksneg, nlockspos + nlocksneg).
    630 *
    631 * Consider the linear constraint "3x -5y +2z <= 7" as an example. The variable rounding lock method of the
    632 * linear constraint handler should call SCIPaddVarLocksType(scip, x, locktype, nlocksneg, nlockspos),
    633 * SCIPaddVarLocksType(scip, y, locktype, nlockspos, nlocksneg) and
    634 * SCIPaddVarLocksType(scip, z, type, nlocksneg, nlockspos) to tell SCIP, that rounding up of x and z and rounding
    635 * down of y can destroy the feasibility of the constraint, while rounding down of x and z and rounding up of y can
    636 * destroy the feasibility of the constraint's negation "3x -5y +2z > 7".
    637 * A linear constraint "2 <= 3x -5y +2z <= 7" should call
    638 * SCIPaddVarLocksType(scip, ..., nlockspos + nlocksneg, nlockspos + nlocksneg) on all variables, since rounding in both
    639 * directions of each variable can destroy both the feasibility of the constraint and it's negation
    640 * "3x -5y +2z < 2 or 3x -5y +2z > 7".
    641 *
    642 * If the constraint itself contains other constraints as sub constraints (e.g. the "or" constraint concatenation
    643 * "c(x) or d(x)"), the rounding lock methods of these constraints should be called in a proper way.
    644 * - If the constraint may get violated by the violation of the sub constraint c, it should call
    645 * SCIPaddConsLocksType(scip, c, locktype, nlockspos, nlocksneg), saying that infeasibility of c may lead to
    646 * infeasibility of the (positive) constraint, and infeasibility of c's negation (i.e. feasibility of c) may lead
    647 * to infeasibility of the constraint's negation (i.e. feasibility of the constraint).
    648 * - If the constraint may get violated by the feasibility of the sub constraint c, it should call
    649 * SCIPaddConsLocksType(scip, c, locktype, nlocksneg, nlockspos), saying that infeasibility of c may lead to
    650 * infeasibility of the constraint's negation (i.e. feasibility of the constraint), and infeasibility of c's negation
    651 * (i.e. feasibility of c) may lead to infeasibility of the (positive) constraint.
    652 * - If the constraint may get violated by any change in the feasibility of the sub constraint c, it should call
    653 * SCIPaddConsLocksType(scip, c, locktype, nlockspos + nlocksneg, nlockspos + nlocksneg).
    654 *
    655 * Consider the or concatenation "c(x) or d(x)". The variable rounding lock method of the or constraint handler
    656 * should call SCIPaddConsLocksType(scip, c, locktype, nlockspos, nlocksneg) and
    657 * SCIPaddConsLocksType(scip, d, locktype, nlockspos, nlocksneg) to tell SCIP, that infeasibility of c and d can lead
    658 * to infeasibility of "c(x) or d(x)".
    659 *
    660 * As a second example, consider the equivalence constraint "y <-> c(x)" with variable y and constraint c. The
    661 * constraint demands, that y == 1 if and only if c(x) is satisfied. The variable lock method of the corresponding
    662 * constraint handler should call SCIPaddVarLocksType(scip, y, locktype, nlockspos + nlocksneg, nlockspos + nlocksneg) and
    663 * SCIPaddConsLocksType(scip, c, locktype, nlockspos + nlocksneg, nlockspos + nlocksneg), because any modification to the
    664 * value of y or to the feasibility of c can alter the feasibility of the equivalence constraint.
    665 *
    666 * input:
    667 * - scip : SCIP main data structure
    668 * - conshdlr : the constraint handler itself
    669 * - cons : the constraint that should lock rounding of its variables, or NULL if the constraint handler
    670 * does not need constraints
    671 * - locktype : type of rounding locks, i.e., SCIP_LOCKTYPE_MODEL or SCIP_LOCKTYPE_CONFLICT
    672 * - nlockspos : number of times, the roundings should be locked for the constraint (may be negative)
    673 * - nlocksneg : number of times, the roundings should be locked for the constraint's negation (may be negative)
    674 */
    675#define SCIP_DECL_CONSLOCK(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS* cons, SCIP_LOCKTYPE locktype, int nlockspos, int nlocksneg)
    676
    677/** constraint activation notification method of constraint handler
    678 *
    679 * WARNING! There may exist unprocessed events. For example, a variable's bound may have been already changed, but
    680 * the corresponding bound change event was not yet processed.
    681 *
    682 * This method is always called after a constraint of the constraint handler was activated. The constraint
    683 * handler may use this call to update his own (statistical) data.
    684 *
    685 * input:
    686 * - scip : SCIP main data structure
    687 * - conshdlr : the constraint handler itself
    688 * - cons : the constraint that has been activated
    689 */
    690#define SCIP_DECL_CONSACTIVE(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS* cons)
    691
    692/** constraint deactivation notification method of constraint handler
    693 *
    694 * WARNING! There may exist unprocessed events. For example, a variable's bound may have been already changed, but
    695 * the corresponding bound change event was not yet processed.
    696 *
    697 * This method is always called before a constraint of the constraint handler is deactivated. The constraint
    698 * handler may use this call to update his own (statistical) data.
    699 *
    700 * input:
    701 * - scip : SCIP main data structure
    702 * - conshdlr : the constraint handler itself
    703 * - cons : the constraint that will be deactivated
    704 */
    705#define SCIP_DECL_CONSDEACTIVE(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS* cons)
    706
    707/** constraint enabling notification method of constraint handler
    708 *
    709 * WARNING! There may exist unprocessed events. For example, a variable's bound may have been already changed, but
    710 * the corresponding bound change event was not yet processed.
    711 *
    712 * This method is always called after a constraint of the constraint handler was enabled. The constraint
    713 * handler may use this call to update his own (statistical) data.
    714 *
    715 * input:
    716 * - scip : SCIP main data structure
    717 * - conshdlr : the constraint handler itself
    718 * - cons : the constraint that has been enabled
    719 */
    720#define SCIP_DECL_CONSENABLE(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS* cons)
    721
    722/** constraint disabling notification method of constraint handler
    723 *
    724 * WARNING! There may exist unprocessed events. For example, a variable's bound may have been already changed, but
    725 * the corresponding bound change event was not yet processed.
    726 *
    727 * This method is always called before a constraint of the constraint handler is disabled. The constraint
    728 * handler may use this call to update his own (statistical) data.
    729 *
    730 * input:
    731 * - scip : SCIP main data structure
    732 * - conshdlr : the constraint handler itself
    733 * - cons : the constraint that will be disabled
    734 */
    735#define SCIP_DECL_CONSDISABLE(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS* cons)
    736
    737/** variable deletion method of constraint handler
    738 *
    739 * This method is optinal and only of interest if you are using SCIP as a branch-and-price framework. That means, you
    740 * are generating new variables during the search. If you are not doing that just define the function pointer to be
    741 * NULL.
    742 *
    743 * If this method gets implemented you should iterate over all constraints of the constraint handler and delete all
    744 * variables that were marked for deletion by SCIPdelVar().
    745 *
    746 * input:
    747 * - scip : SCIP main data structure
    748 * - conshdlr : the constraint handler itself
    749 * - conss : array of constraints in transformed problem
    750 * - nconss : number of constraints in transformed problem
    751 */
    752#define SCIP_DECL_CONSDELVARS(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS** conss, int nconss)
    753
    754/** constraint display method of constraint handler
    755 *
    756 * The constraint handler can store a representation of the constraint into the given text file. Use the method
    757 * SCIPinfoMessage() to push a string into the file stream.
    758 *
    759 * @note There are several methods which help to display variables. These are SCIPwriteVarName(), SCIPwriteVarsList(),
    760 * SCIPwriteVarsLinearsum(), and SCIPwriteVarsPolynomial().
    761 *
    762 * input:
    763 * - scip : SCIP main data structure
    764 * - conshdlr : the constraint handler itself
    765 * - cons : the constraint that should be displayed
    766 * - file : the text file to store the information into
    767 */
    768#define SCIP_DECL_CONSPRINT(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS* cons, FILE* file)
    769
    770/** constraint copying method of constraint handler
    771 *
    772 * The constraint handler can provide a copy method which copies a constraint from one SCIP data structure into an other
    773 * SCIP data structure. If a copy of a constraint is created, the constraint has to be captured. (The capture is usually
    774 * already done due to the creation of the constraint).
    775 *
    776 * If the copy process was one to one, the valid pointer can be set to TRUE. Otherwise, you have to set this pointer to
    777 * FALSE. In case all problem defining objects (constraint handlers and variable pricers) return a TRUE valid for all
    778 * their copying calls, SCIP assumes that it is a overall one to one copy of the original instance. In this case any
    779 * reductions made in the copied SCIP instance can be transfered to the original SCIP instance. If the valid pointer is
    780 * set to TRUE and it was not a one to one copy, it might happen that optimal solutions are cut off.
    781 *
    782 * To get a copy of a variable in the target SCIP you should use the function SCIPgetVarCopy().
    783 *
    784 * input:
    785 * - scip : target SCIP data structure
    786 * - cons : pointer to store the created target constraint
    787 * - name : name of constraint, or NULL if the name of the source constraint should be used
    788 * - sourcescip : source SCIP data structure
    789 * - sourceconshdlr : source constraint handler of the source SCIP
    790 * - sourcecons : source constraint of the source SCIP
    791 * - varmap : a SCIP_HASHMAP mapping variables of the source SCIP to corresponding variables of the target SCIP
    792 * - consmap : a SCIP_HASHMAP mapping constraints of the source SCIP to corresponding constraints of the target SCIP
    793 * - initial : should the LP relaxation of constraint be in the initial LP?
    794 * - separate : should the constraint be separated during LP processing?
    795 * - enforce : should the constraint be enforced during node processing?
    796 * - check : should the constraint be checked for feasibility?
    797 * - propagate : should the constraint be propagated during node processing?
    798 * - local : is constraint only valid locally?
    799 * - modifiable : is constraint modifiable (subject to column generation)?
    800 * - dynamic : is constraint subject to aging?
    801 * - removable : should the relaxation be removed from the LP due to aging or cleanup?
    802 * - stickingatnode : should the constraint always be kept at the node where it was added, even
    803 * if it may be moved to a more global node?
    804 * - global : should a global or a local copy be created?
    805 *
    806 * output:
    807 * - valid : pointer to store whether the copying was valid or not
    808 */
    809#define SCIP_DECL_CONSCOPY(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONS** cons, const char* name, \
    810 SCIP* sourcescip, SCIP_CONSHDLR* sourceconshdlr, SCIP_CONS* sourcecons, SCIP_HASHMAP* varmap, SCIP_HASHMAP* consmap, \
    811 SCIP_Bool initial, SCIP_Bool separate, SCIP_Bool enforce, SCIP_Bool check, SCIP_Bool propagate, \
    812 SCIP_Bool local, SCIP_Bool modifiable, SCIP_Bool dynamic, SCIP_Bool removable, SCIP_Bool stickingatnode, \
    813 SCIP_Bool global, SCIP_Bool* valid)
    814
    815/** constraint parsing method of constraint handler
    816 *
    817 * The constraint handler can provide a callback to parse the output created by the display method
    818 * (\ref SCIP_DECL_CONSPRINT) and to create a constraint out of it.
    819 *
    820 * @note For parsing there are several methods which are handy. Have a look at: SCIPparseVarName(),
    821 * SCIPparseVarsList(), SCIPparseVarsLinearsum(), SCIPparseVarsPolynomial(), SCIPstrToRealValue(), and
    822 * SCIPstrCopySection().
    823 *
    824 * input:
    825 * - scip : SCIP main data structure
    826 * - conshdlr : the constraint handler itself
    827 * - cons : pointer to store the created constraint
    828 * - name : name of the constraint
    829 * - str : string to parse
    830 * - initial : should the LP relaxation of constraint be in the initial LP?
    831 * - separate : should the constraint be separated during LP processing?
    832 * - enforce : should the constraint be enforced during node processing?
    833 * - check : should the constraint be checked for feasibility?
    834 * - propagate : should the constraint be propagated during node processing?
    835 * - local : is constraint only valid locally?
    836 * - modifiable : is constraint modifiable (subject to column generation)?
    837 * - dynamic : is constraint subject to aging?
    838 * - removable : should the relaxation be removed from the LP due to aging or cleanup?
    839 * - stickingatnode : should the constraint always be kept at the node where it was added, even
    840 * if it may be moved to a more global node?
    841 * output:
    842 * - success : pointer to store whether the parsing was successful or not
    843 */
    844#define SCIP_DECL_CONSPARSE(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS** cons, \
    845 const char* name, const char* str, \
    846 SCIP_Bool initial, SCIP_Bool separate, SCIP_Bool enforce, SCIP_Bool check, SCIP_Bool propagate, SCIP_Bool local, \
    847 SCIP_Bool modifiable, SCIP_Bool dynamic, SCIP_Bool removable, SCIP_Bool stickingatnode, SCIP_Bool* success)
    848
    849/** constraint method of constraint handler which returns the variables (if possible)
    850 *
    851 * The constraint handler can (this callback is optional) provide this callback to return the variables which are
    852 * involved in that particular constraint. If this is possible, the variables should be copyied into the variables
    853 * array and the success pointers has to be set to TRUE. Otherwise the success has to be set FALSE or the callback
    854 * should not be implemented.
    855 *
    856 * input:
    857 * - scip : SCIP main data structure
    858 * - conshdlr : the constraint handler itself
    859 * - cons : the constraint that should return its variable data
    860 * - varssize : available slots in vars array which is needed to check if the array is large enough
    861 *
    862 * output:
    863 * - vars : array to store/copy the involved variables of the constraint
    864 * - success : pointer to store whether the variables are successfully copied
    865 */
    866#define SCIP_DECL_CONSGETVARS(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS* cons, \
    867 SCIP_VAR** vars, int varssize, SCIP_Bool* success)
    868
    869/** constraint method of constraint handler which returns the number of variables (if possible)
    870 *
    871 * The constraint handler can (this callback is optional) provide this callback to return the number variable which are
    872 * involved in that particular constraint. If this is not possible, the success pointers has to be set to FALSE or the
    873 * callback should not be implemented.
    874 *
    875 * input:
    876 * - scip : SCIP main data structure
    877 * - conshdlr : the constraint handler itself
    878 * - cons : constraint for which the number of variables is wanted
    879 *
    880 * output:
    881 * - nvars : pointer to store the number of variables
    882 * - success : pointer to store whether the constraint successfully returned the number of variables
    883 */
    884#define SCIP_DECL_CONSGETNVARS(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS* cons, \
    885 int* nvars, SCIP_Bool* success)
    886
    887/** constraint handler method to suggest dive bound changes during the generic diving algorithm
    888 *
    889 * This callback is used inside the various diving heuristics of SCIP and does not affect the normal branching of the
    890 * actual search. The constraint handler can provide this callback to render the current solution (even more)
    891 * infeasible by suggesting one or several variable bound changes. In fact, since diving heuristics do not necessarily
    892 * solve LP relaxations at every probing depth, some of the variable local bounds might already be conflicting with the
    893 * solution values. The solution is rendered infeasible by determining bound changes that should be applied to the
    894 * next explored search node via SCIPaddDiveBoundChange(). An alternative in case that the preferred bound change(s)
    895 * were detected infeasible must be provided.
    896 *
    897 * The constraint handler must take care to only add bound changes that further shrink the variable domain.
    898 *
    899 * The success pointer must be used to indicate whether the constraint handler succeeded in selecting diving bound
    900 * changes. The infeasible pointer should be set to TRUE if the constraint handler found a local infeasibility. If the
    901 * constraint handler needs to select between several candidates, it may use the scoring mechanism of the diveset
    902 * argument to control its choice.
    903 *
    904 * This callback is optional.
    905 *
    906 * @note: @p sol is usually the LP relaxation solution unless the caller of the method, usually a diving heuristic,
    907 * does not solve LP relaxations at every depth
    908 *
    909 * input:
    910 * - scip : SCIP main data structure
    911 * - conshdlr : the constraint handler itself
    912 * - diveset : diving settings for scoring
    913 * - sol : current diving solution, usually the LP relaxation solution
    914 *
    915 * output:
    916 * - success : pointer to store whether the constraint handler succeeded to determine dive bound changes
    917 * - infeasible : pointer to store whether the constraint handler detected an infeasibility in the local node
    918 */
    919#define SCIP_DECL_CONSGETDIVEBDCHGS(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_DIVESET* diveset, \
    920 SCIP_SOL* sol, SCIP_Bool* success, SCIP_Bool* infeasible)
    921
    922/** constraint handler method which returns the permutation symmetry detection graph of a constraint (if possible)
    923 *
    924 * The constraint handler can (this callback is optional) provide this callback to return a graph that encodes the
    925 * permutation symmetries of a constraint. If this is not possible, the success pointer has to be set to FALSE or the
    926 * callback should not be implemented.
    927 *
    928 * input:
    929 * - scip : SCIP main data structure
    930 * - conshdlr : the constraint handler itself
    931 * - cons : constraint for which the symmetry detection graph is requested
    932 *
    933 * output:
    934 * - graph : symmetry detection graph
    935 * - success : pointer to store whether the constraint successfully returned the symmetry detection graph
    936 */
    937#define SCIP_DECL_CONSGETPERMSYMGRAPH(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS* cons, \
    938 SYM_GRAPH* graph, SCIP_Bool* success)
    939
    940/** constraint handler method providing the signed permutation symmetry detection graph of a constraint (if possible)
    941 *
    942 * The constraint handler can (this callback is optional) provide this callback to return a graph that encodes the
    943 * signed permutation symmetries of a constraint. If this is not possible, the success pointer has to be set to FALSE
    944 * or the callback should not be implemented.
    945 *
    946 * input:
    947 * - scip : SCIP main data structure
    948 * - conshdlr : the constraint handler itself
    949 * - cons : constraint for which the symmetry detection graph is requested
    950 *
    951 * output:
    952 * - graph : symmetry detection graph
    953 * - success : pointer to store whether the constraint successfully returned the symmetry detection graph
    954 */
    955#define SCIP_DECL_CONSGETSIGNEDPERMSYMGRAPH(x) SCIP_RETCODE x (SCIP* scip, SCIP_CONSHDLR* conshdlr, SCIP_CONS* cons, \
    956 SYM_GRAPH* graph, SCIP_Bool* success)
    957
    958#ifdef __cplusplus
    959}
    960#endif
    961
    962#endif
    common defines and data types used in all packages of SCIP
    struct SCIP_ConshdlrData SCIP_CONSHDLRDATA
    Definition: type_cons.h:64
    SCIP_LinConstype
    Definition: type_cons.h:72
    @ SCIP_LINCONSTYPE_BINPACKING
    Definition: type_cons.h:85
    @ SCIP_LINCONSTYPE_VARBOUND
    Definition: type_cons.h:78
    @ SCIP_LINCONSTYPE_EMPTY
    Definition: type_cons.h:73
    @ SCIP_LINCONSTYPE_INVKNAPSACK
    Definition: type_cons.h:83
    @ SCIP_LINCONSTYPE_PRECEDENCE
    Definition: type_cons.h:77
    @ SCIP_LINCONSTYPE_AGGREGATION
    Definition: type_cons.h:76
    @ SCIP_LINCONSTYPE_MIXEDBINARY
    Definition: type_cons.h:88
    @ SCIP_LINCONSTYPE_SINGLETON
    Definition: type_cons.h:75
    @ SCIP_LINCONSTYPE_SETCOVERING
    Definition: type_cons.h:81
    @ SCIP_LINCONSTYPE_EQKNAPSACK
    Definition: type_cons.h:84
    @ SCIP_LINCONSTYPE_FREE
    Definition: type_cons.h:74
    @ SCIP_LINCONSTYPE_KNAPSACK
    Definition: type_cons.h:86
    @ SCIP_LINCONSTYPE_SETPARTITION
    Definition: type_cons.h:79
    @ SCIP_LINCONSTYPE_INTKNAPSACK
    Definition: type_cons.h:87
    @ SCIP_LINCONSTYPE_SETPACKING
    Definition: type_cons.h:80
    @ SCIP_LINCONSTYPE_GENERAL
    Definition: type_cons.h:89
    @ SCIP_LINCONSTYPE_CARDINALITY
    Definition: type_cons.h:82
    struct SCIP_ConsData SCIP_CONSDATA
    Definition: type_cons.h:65
    enum SCIP_LinConstype SCIP_LINCONSTYPE
    Definition: type_cons.h:91
    type definitions for primal heuristics
    type definitions for LP management
    result codes for SCIP callback methods
    type definitions for return codes for SCIP methods
    type definitions for SCIP's main datastructure
    type definitions for storing primal CIP solutions
    timing definitions for SCIP
    type definitions for problem variables