Scippy

SCIP

Solving Constraint Integer Programs

struct_implics.h
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1/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
2/* */
3/* This file is part of the program and library */
4/* SCIP --- Solving Constraint Integer Programs */
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7/* */
8/* Licensed under the Apache License, Version 2.0 (the "License"); */
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23/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
24
25/**@file struct_implics.h
26 * @ingroup INTERNALAPI
27 * @brief datastructures for implications, variable bounds, and cliques
28 * @author Tobias Achterberg
29 */
30
31/*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
32
33#ifndef __SCIP_STRUCT_IMPLICS_H__
34#define __SCIP_STRUCT_IMPLICS_H__
35
36
37#include "scip/def.h"
38#include "scip/type_implics.h"
39#include "scip/type_lp.h"
40#include "scip/type_misc.h"
41#include "scip/type_var.h"
42
43#ifdef __cplusplus
44extern "C" {
45#endif
46
47/** variable bounds of a variable x in the form x <= b*z + d or x >= b*z + d */
49{
50 SCIP_VAR** vars; /**< variables z in variable bounds x <= b*z + d or x >= b*z + d */
51 SCIP_Real* coefs; /**< coefficients b in variable bounds x <= b*z + d or x >= b*z + d */
52 SCIP_Real* constants; /**< constants d in variable bounds x <= b*z + d or x >= b*z + d */
53 int len; /**< number of existing variable bounds (used slots in arrays) */
54 int size; /**< size of vars, coefs, and constants arrays */
55};
56
57/** implications for binary variable x to non-binary variables y in the form
58 * x <= 0 ==> y <= b or y >= b (stored in arrays[0])
59 * x >= 1 ==> y <= b or y >= b (stored in arrays[1])
60 * array is sorted by variable index of y
61 */
63{
64 SCIP_VAR** vars[2]; /**< variables y in implications y <= b or y >= b */
65 SCIP_BOUNDTYPE* types[2]; /**< types of implications y <= b (SCIP_BOUNDTYPE_UPPER)
66 * or y >= b (SCIP_BOUNDTYPE_LOWER) */
67 SCIP_Real* bounds[2]; /**< bounds b in implications y <= b or y >= b */
68 int* ids[2]; /**< unique ids of implications; < 0 iff implication is a shortcut,
69 * i.e., it was added as part of the transitive closure of another implication */
70 int size[2]; /**< size of implvars, implbounds and implvals arrays for x <= 0 and x >= 1*/
71 int nimpls[2]; /**< number of all implications for x <= 0 and x >= 1 */
72};
73
74/** single clique, stating that at most one of the binary variables can be fixed to the corresponding value */
76{
77 SCIP_VAR** vars; /**< variables in the clique */
78 SCIP_Bool* values; /**< values of the variables in the clique */
79 int nvars; /**< number of variables in the clique */
80 int size; /**< size of vars and values arrays */
81 int startcleanup; /**< clean up position to start with */
82 int index; /**< the index of the clique in the cliquetable cliques array */
83 unsigned int id:30; /**< unique identifier of clique */
84 unsigned int eventsissued:1; /**< were the IMPLADDED events on the variables already issued? */
85 unsigned int equation:1; /**< is the clique an equation or an inequality? */
86};
87
88/** list of cliques for a single variable */
90{
91 SCIP_CLIQUE** cliques[2]; /**< cliques the variable fixed to FALSE/TRUE is member of */
92 int ncliques[2]; /**< number of cliques the variable fixed to FALSE/TRUE is member of */
93 int size[2]; /**< size of cliques arrays */
94};
95
96/** collection of cliques */
98{
99 SCIP_HASHTABLE* hashtable; /**< hash table holding all cliques */
100 SCIP_HASHMAP* varidxtable; /**< mapping from binary variable to their corresponding node indices */
101 SCIP_DISJOINTSET* djset; /**< disjoint set (union find) data structure to maintain component information */
102 SCIP_CLIQUE** cliques; /**< cliques stored in the table */
103 SCIP_Longint nentries; /**< number of entries in the whole clique table */
104 int ncliques; /**< number of cliques stored in the table */
105 int size; /**< size of cliques array */
106 int ncreatedcliques; /**< number of ever created cliques */
107 int ncleanupfixedvars; /**< number of fixed variables when the last cleanup was performed */
108 int ncleanupaggrvars; /**< number of aggregated variables when the last cleanup was performed */
109 int ndirtycliques; /**< number of cliques stored when the last cleanup was performed */
110 int ncliquecomponents; /**< number of connected components in clique graph */
111 SCIP_Bool incleanup; /**< is this clique table currently performing cleanup? */
112 SCIP_Bool compsfromscratch; /**< must the connected components of the clique graph be recomputed from scratch? */
113};
114
115#ifdef __cplusplus
116}
117#endif
118
119#endif
common defines and data types used in all packages of SCIP
#define SCIP_Longint
Definition: def.h:158
#define SCIP_Bool
Definition: def.h:91
#define SCIP_Real
Definition: def.h:173
SCIP_CLIQUE ** cliques[2]
SCIP_HASHTABLE * hashtable
SCIP_CLIQUE ** cliques
SCIP_DISJOINTSET * djset
SCIP_Longint nentries
SCIP_HASHMAP * varidxtable
SCIP_Bool compsfromscratch
unsigned int equation
SCIP_Bool * values
unsigned int eventsissued
SCIP_VAR ** vars
unsigned int id
SCIP_BOUNDTYPE * types[2]
int * ids[2]
SCIP_VAR ** vars[2]
SCIP_Real * bounds[2]
SCIP_Real * constants
SCIP_VAR ** vars
SCIP_Real * coefs
type definitions for implications, variable bounds, and cliques
type definitions for LP management
enum SCIP_BoundType SCIP_BOUNDTYPE
Definition: type_lp.h:59
type definitions for miscellaneous datastructures
type definitions for problem variables