Scippy

SCIP

Solving Constraint Integer Programs

struct_symmetry.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 */
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 struct_symmetry.h
26 * @brief structs for symmetry computations
27 * @author Marc Pfetsch
28 * @author Christopher Hojny
29 */
30
31/*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
32
33#ifndef __SCIP_STRUCT_SYMMETRY_H_
34#define __SCIP_STRUCT_SYMMETRY_H_
35
36#include "scip/scip.h"
38#include "scip/type_expr.h"
39
40#ifdef __cplusplus
41extern "C" {
42#endif
43
44/** data to encode a symmetry detection graph */
46{
47 /* general information about graph */
48 SYM_SYMTYPE symtype; /**< type of symmetries encoded in graph */
49 SCIP_Bool islocked; /**< whether graph is locked, i.e., cannot be modified anymore
50 * (computing colors will lock the graph to avoid inconsistencies) */
51 SCIP_Real infinity; /**< values as least as large as this are regarded as infinite */
52
53 /* information about nodes and node arrays */
54 int nnodes; /**< number of nodes in graph */
55 int maxnnodes; /**< maximum number of entries in node-based arrays */
56 int nopnodes; /**< number of operator nodes in graph */
57 int maxnopnodes; /**< maximum number of entries in operator-based arrays */
58 int nvalnodes; /**< number of value nodes in graph */
59 int maxnvalnodes; /**< maximum number of entries in value-based arrays */
60 int nconsnodes; /**< number of constraint nodes */
61 int maxnconsnodes; /**< maximum number of constraint-based arrays */
62 int nvarcolors; /**< number of variable colors */
63
64 /* node-based arrays */
65 SYM_NODETYPE* nodetypes; /**< array storing each node's type */
66 int* nodeinfopos; /**< array assigning each node the position in the corresponding array
67 * containing its information (operator, variable, or value) */
68 int* consnodeperm; /**< array to hold permutation to sort constraint nodes
69 * (graph needs to be locked to avoid inconsistencies) */
70
71 /* information-based arrays */
72 int* ops; /**< operators corresponding to nodes in graph */
73 SCIP_Real* vals; /**< values corresponding to nodes in graph */
74 SCIP_CONS** conss; /**< constraints corresponding to cons nodes */
75 SCIP_Real* lhs; /**< array of left-hand sides for cons nodes */
76 SCIP_Real* rhs; /**< array of right-hand sides for cons nodes */
77
78 /* information about edges and edge arrays */
79 int nedges; /**< number of edges in graph */
80 int maxnedges; /**< maximum number of entries in edge-based arrays */
81
82 /* edge-based arrays; negative entries in edge-first and edge-second correspond to variables */
83 int* edgefirst; /**< array of first nodes of edges */
84 int* edgesecond; /**< array of second nodes of edges */
85 SCIP_Real* edgevals; /**< array assigning each edge a value (SCIPinfinity if unassigned) */
86
87 /* information about variables */
88 SCIP_VAR** symvars; /**< variables on which symmetries act */
89 int nsymvars; /**< number of variables in symvars */
90 SCIP_Bool* isfixedvar; /**< whether a variable needs to be fixed */
91
92 /* arrays of colors used for symmetry detection */
93 int* varcolors; /**< variable colors for symmetry detection */
94 int* opcolors; /**< operator colors for symmetry detection */
95 int* valcolors; /**< value colors for symmetry detection */
96 int* conscolors; /**< constraint colors for symmetry detection */
97 int* edgecolors; /**< edge colors used for symmetry detection (-1 uncolored) */
98 SCIP_Bool uniqueedgetype; /**< whether all edges are equivalent */
99};
100
101/** (additional) data used to encode an expression, which is not encoded as another expression */
103{
104 SCIP_Real* constants; /**< constants used in an expression */
105 int nconstants; /**< number of constants */
106 SCIP_Real* coefficients; /**< coefficients of children */
107 int ncoefficients; /**< number of coefficients */
108 SCIP_EXPR** children; /**< children of expression with a coefficient */
109};
110
111#ifdef __cplusplus
112}
113#endif
114
115#endif
#define SCIP_Bool
Definition: def.h:91
#define SCIP_Real
Definition: def.h:173
SCIP callable library.
SCIP_EXPR ** children
SCIP_Real * coefficients
SCIP_Real * constants
int * nodeinfopos
int * conscolors
SCIP_Real infinity
SYM_NODETYPE * nodetypes
int * valcolors
SCIP_Real * edgevals
int * varcolors
int * consnodeperm
int * edgefirst
SCIP_VAR ** symvars
SCIP_Bool * isfixedvar
SCIP_Real * vals
int * edgecolors
SCIP_Real * rhs
SCIP_Bool islocked
SCIP_Bool uniqueedgetype
SCIP_Real * lhs
SCIP_CONS ** conss
int * opcolors
SYM_SYMTYPE symtype
int * edgesecond
type and macro definitions related to algebraic expressions
type definitions for symmetry computations
enum SYM_Symtype SYM_SYMTYPE
Definition: type_symmetry.h:64
enum SYM_Nodetype SYM_NODETYPE
Definition: type_symmetry.h:74