Scippy

SCIP

Solving Constraint Integer Programs

type_sepa.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) 2002-2024 Zuse Institute Berlin (ZIB) */
7/* */
8/* Licensed under the Apache License, Version 2.0 (the "License"); */
9/* you may not use this file except in compliance with the License. */
10/* You may obtain a copy of the License at */
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12/* http://www.apache.org/licenses/LICENSE-2.0 */
13/* */
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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_sepa.h
26 * @ingroup TYPEDEFINITIONS
27 * @brief type definitions for separators
28 * @author Tobias Achterberg
29 */
30
31/** @defgroup DEFPLUGINS_SEPA Default Separators
32 * @ingroup DEFPLUGINS
33 * @brief implementation files (.c files) of the default separators of SCIP
34 */
35
36/*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
37
38#ifndef __SCIP_TYPE_SEPA_H__
39#define __SCIP_TYPE_SEPA_H__
40
41#include "scip/def.h"
42#include "scip/type_retcode.h"
43#include "scip/type_result.h"
44#include "scip/type_sol.h"
45#include "scip/type_scip.h"
46
47#ifdef __cplusplus
48extern "C" {
49#endif
50
51typedef struct SCIP_Sepa SCIP_SEPA; /**< separator */
52typedef struct SCIP_SepaData SCIP_SEPADATA; /**< locally defined separator data */
53
54
55/** copy method for separator plugins (called when SCIP copies plugins)
56 *
57 * input:
58 * - scip : SCIP main data structure
59 * - sepa : the separator itself
60 */
61#define SCIP_DECL_SEPACOPY(x) SCIP_RETCODE x (SCIP* scip, SCIP_SEPA* sepa)
62
63/** destructor of separator to free user data (called when SCIP is exiting)
64 *
65 * input:
66 * - scip : SCIP main data structure
67 * - sepa : the separator itself
68 */
69#define SCIP_DECL_SEPAFREE(x) SCIP_RETCODE x (SCIP* scip, SCIP_SEPA* sepa)
70
71/** initialization method of separator (called after problem was transformed)
72 *
73 * input:
74 * - scip : SCIP main data structure
75 * - sepa : the separator itself
76 */
77#define SCIP_DECL_SEPAINIT(x) SCIP_RETCODE x (SCIP* scip, SCIP_SEPA* sepa)
78
79/** deinitialization method of separator (called before transformed problem is freed)
80 *
81 * input:
82 * - scip : SCIP main data structure
83 * - sepa : the separator itself
84 */
85#define SCIP_DECL_SEPAEXIT(x) SCIP_RETCODE x (SCIP* scip, SCIP_SEPA* sepa)
86
87/** solving process initialization method of separator (called when branch and bound process is about to begin)
88 *
89 * This method is called when the presolving was finished and the branch and bound process is about to begin.
90 * The separator may use this call to initialize its branch and bound specific data.
91 *
92 * input:
93 * - scip : SCIP main data structure
94 * - sepa : the separator itself
95 */
96#define SCIP_DECL_SEPAINITSOL(x) SCIP_RETCODE x (SCIP* scip, SCIP_SEPA* sepa)
97
98/** solving process deinitialization method of separator (called before branch and bound process data is freed)
99 *
100 * This method is called before the branch and bound process is freed.
101 * The separator should use this call to clean up its branch and bound data.
102 *
103 * input:
104 * - scip : SCIP main data structure
105 * - sepa : the separator itself
106 */
107#define SCIP_DECL_SEPAEXITSOL(x) SCIP_RETCODE x (SCIP* scip, SCIP_SEPA* sepa)
108
109/** LP solution separation method of separator
110 *
111 * Searches for cutting planes that separate the current LP solution. The method is called in the LP solving loop,
112 * which means that a valid LP solution exists.
113 *
114 * input:
115 * - scip : SCIP main data structure
116 * - sepa : the separator itself
117 * - result : pointer to store the result of the separation call
118 * - allowlocal : should the separator allow local cuts?
119 * - depth : preteneded depth of current node
120 *
121 * @note The depth argument shouldn't be use to determine whether the cut is globally valid or not. The value of depth
122 * could be 0 even though we are not in the root node! The purpose of depth is to control the behavior of the
123 * separator. Usually separators will have different limits on the number of cuts to be applied in the root node, etc.
124 * These limits should be checked against depth and not against the actual depth of the current node.
125 *
126 * possible return values for *result (if more than one applies, the first in the list should be used):
127 * - SCIP_CUTOFF : the node is infeasible in the variable's bounds and can be cut off
128 * - SCIP_CONSADDED : an additional constraint was generated
129 * - SCIP_REDUCEDDOM : a variable's domain was reduced
130 * - SCIP_SEPARATED : a cutting plane was generated
131 * - SCIP_NEWROUND : a cutting plane was generated and a new separation round should immediately start
132 * - SCIP_DIDNOTFIND : the separator searched, but did not find domain reductions, cutting planes, or cut constraints
133 * - SCIP_DIDNOTRUN : the separator was skipped
134 * - SCIP_DELAYED : the separator was skipped, but should be called again
135 */
136#define SCIP_DECL_SEPAEXECLP(x) SCIP_RETCODE x (SCIP* scip, SCIP_SEPA* sepa, SCIP_RESULT* result, SCIP_Bool allowlocal, int depth)
137
138/** arbitrary primal solution separation method of separator
139 *
140 * Searches for cutting planes that separate the given primal solution. The method is called outside the LP solution
141 * loop (e.g., by a relaxator or a primal heuristic), which means that there is no valid LP solution.
142 *
143 * input:
144 * - scip : SCIP main data structure
145 * - sepa : the separator itself
146 * - sol : primal solution that should be separated
147 * - result : pointer to store the result of the separation call
148 * - allowlocal : should the separator allow local cuts?
149 * - depth : preteneded depth of current node
150 *
151 * @note The depth argument shouldn't be use to determine whether the cut is globally valid or not. The value of depth
152 * could be 0 even though we are not in the root node! The purpose of depth is to control the behavior of the
153 * separator. Usually separators will have different limits on the number of cuts to be applied in the root node, etc.
154 * These limits should be checked against depth and not against the actual depth of the current node.
155 *
156 * possible return values for *result (if more than one applies, the first in the list should be used):
157 * - SCIP_CUTOFF : the node is infeasible in the variable's bounds and can be cut off
158 * - SCIP_CONSADDED : an additional constraint was generated
159 * - SCIP_REDUCEDDOM : a variable's domain was reduced
160 * - SCIP_SEPARATED : a cutting plane was generated
161 * - SCIP_NEWROUND : a cutting plane was generated and a new separation round should immediately start
162 * - SCIP_DIDNOTFIND : the separator searched, but did not find domain reductions, cutting planes, or cut constraints
163 * - SCIP_DIDNOTRUN : the separator was skipped
164 * - SCIP_DELAYED : the separator was skipped, but should be called again
165 */
166#define SCIP_DECL_SEPAEXECSOL(x) SCIP_RETCODE x (SCIP* scip, SCIP_SEPA* sepa, SCIP_SOL* sol, SCIP_RESULT* result, SCIP_Bool allowlocal, int depth)
167
168#ifdef __cplusplus
169}
170#endif
171
172#endif
def.h
common defines and data types used in all packages of SCIP
SCIP_Sepa
Definition: struct_sepa.h:47
type_result.h
result codes for SCIP callback methods
type_retcode.h
type definitions for return codes for SCIP methods
type_scip.h
type definitions for SCIP's main datastructure
SCIP_SEPADATA
struct SCIP_SepaData SCIP_SEPADATA
Definition: type_sepa.h:52
type_sol.h
type definitions for storing primal CIP solutions