Scippy

SCIP

Solving Constraint Integer Programs

struct_var.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) 2002-2023 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 /* */
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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, */
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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_var.h
26  * @ingroup INTERNALAPI
27  * @brief datastructures for problem variables
28  * @author Tobias Achterberg
29  */
30 
31 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
32 
33 #ifndef __SCIP_STRUCT_VAR_H__
34 #define __SCIP_STRUCT_VAR_H__
35 
36 
37 #include "scip/def.h"
38 #include "scip/type_history.h"
39 #include "scip/type_event.h"
40 #include "scip/type_var.h"
41 #include "scip/type_implics.h"
42 #include "scip/type_cons.h"
43 #include "scip/type_prop.h"
44 #include "scip/type_lp.h"
45 
46 #ifdef __cplusplus
47 extern "C" {
48 #endif
49 
50 /** hole in a domain */
51 struct SCIP_Hole
52 {
53  SCIP_Real left; /**< left bound of open interval defining the hole (left,right) */
54  SCIP_Real right; /**< right bound of open interval defining the hole (left,right) */
55 };
56 
57 /** list of domain holes */
59 {
60  SCIP_HOLE hole; /**< this hole */
61  SCIP_HOLELIST* next; /**< next hole in list */
62 };
63 
64 /** change in a hole list */
66 {
67  SCIP_HOLELIST** ptr; /**< changed list pointer */
68  SCIP_HOLELIST* newlist; /**< new value of list pointer */
69  SCIP_HOLELIST* oldlist; /**< old value of list pointer */
70 };
71 
72 /** data for branching decision bound changes */
73 struct SCIP_BranchingData
74 {
75  SCIP_Real lpsolval; /**< sol val of var in last LP prior to bound change, or SCIP_INVALID if unknown */
76 };
77 
78 /** data for inferred bound changes */
79 struct SCIP_InferenceData
80 {
81  SCIP_VAR* var; /**< variable that was changed (parent of var, or var itself) */
82  union
83  {
84  SCIP_CONS* cons; /**< constraint that inferred this bound change, or NULL */
85  SCIP_PROP* prop; /**< propagator that inferred this bound change, or NULL */
86  } reason;
87  int info; /**< user information for inference to help resolving the conflict */
88 };
89 
90 /** change in one bound of a variable */
92 {
93  SCIP_Real newbound; /**< new value for bound */
94  union
95  {
96  SCIP_BRANCHINGDATA branchingdata; /**< data for branching decisions */
97  SCIP_INFERENCEDATA inferencedata; /**< data for inferred bound changes */
98  } data;
99  SCIP_VAR* var; /**< active variable to change the bounds for */
100  unsigned int boundchgtype:2; /**< bound change type: branching decision or inferred bound change */
101  unsigned int boundtype:1; /**< type of bound for var: lower or upper bound */
102  unsigned int inferboundtype:1; /**< type of bound for inference var (see inference data): lower or upper bound */
103  unsigned int applied:1; /**< was this bound change applied at least once? */
104  unsigned int redundant:1; /**< is this bound change redundant? */
105 };
106 
107 /** bound change index representing the time of the bound change in path from root to current node */
109 {
110  int depth; /**< depth of node where the bound change was created */
111  int pos; /**< position of bound change in node's domchg array */
112 };
113 
114 /** bound change information to track bound changes from root node to current node */
116 {
117  SCIP_Real oldbound; /**< old value for bound */
118  SCIP_Real newbound; /**< new value for bound */
119  SCIP_VAR* var; /**< active variable that changed the bounds */
120  SCIP_INFERENCEDATA inferencedata; /**< data for inferred bound changes */
121  SCIP_BDCHGIDX bdchgidx; /**< bound change index in path from root to current node */
122  unsigned int pos:27; /**< position in the variable domain change array */
123  unsigned int boundchgtype:2; /**< bound change type: branching decision or inferred bound change */
124  unsigned int boundtype:1; /**< type of bound for var: lower or upper bound */
125  unsigned int inferboundtype:1; /**< type of bound for inference var (see inference data): lower or upper bound */
126  unsigned int redundant:1; /**< does the bound change info belong to a redundant bound change? */
127 };
128 
129 /** tracks changes of the variables' domains (static arrays, bound changes only) */
131 {
132  unsigned int nboundchgs:30; /**< number of bound changes (must be first structure entry!) */
133  unsigned int domchgtype:2; /**< type of domain change data (must be first structure entry!) */
134  SCIP_BOUNDCHG* boundchgs; /**< array with changes in bounds of variables */
135 };
136 
137 /** tracks changes of the variables' domains (static arrays, bound and hole changes) */
139 {
140  unsigned int nboundchgs:30; /**< number of bound changes (must be first structure entry!) */
141  unsigned int domchgtype:2; /**< type of domain change data (must be first structure entry!) */
142  SCIP_BOUNDCHG* boundchgs; /**< array with changes in bounds of variables */
143  SCIP_HOLECHG* holechgs; /**< array with changes in hole lists */
144  int nholechgs; /**< number of hole list changes */
145 };
146 
147 /** tracks changes of the variables' domains (dynamic arrays) */
149 {
150  unsigned int nboundchgs:30; /**< number of bound changes (must be first structure entry!) */
151  unsigned int domchgtype:2; /**< type of domain change data (must be first structure entry!) */
152  SCIP_BOUNDCHG* boundchgs; /**< array with changes in bounds of variables */
153  SCIP_HOLECHG* holechgs; /**< array with changes in hole lists */
154  int nholechgs; /**< number of hole list changes */
155  int boundchgssize; /**< size of bound changes array */
156  int holechgssize; /**< size of hole changes array */
157 };
158 
159 /** tracks changes of the variables' domains */
161 {
162  SCIP_DOMCHGBOUND domchgbound; /**< bound changes */
163  SCIP_DOMCHGBOTH domchgboth; /**< bound and hole changes */
164  SCIP_DOMCHGDYN domchgdyn; /**< bound and hole changes with dynamic arrays */
165 };
166 
167 /** domain of a variable */
168 struct SCIP_Dom
169 {
170  SCIP_Real lb; /**< lower bounds of variables */
171  SCIP_Real ub; /**< upper bounds of variables */
172  SCIP_HOLELIST* holelist; /**< list of holes */
173 };
174 
175 /** original variable information */
177 {
178  SCIP_DOM origdom; /**< domain of variable in original problem */
179  SCIP_VAR* transvar; /**< pointer to representing transformed variable */
180 };
181 
182 /** aggregation information: x = a*y + c */
184 {
185  SCIP_Real scalar; /**< multiplier a in aggregation */
186  SCIP_Real constant; /**< constant shift c in aggregation */
187  SCIP_VAR* var; /**< variable y in aggregation */
188 };
189 
190 /** multiple aggregation information: x = a_1*y_1 + ... + a_k*y_k + c */
192 {
193  SCIP_Real constant; /**< constant shift c in multiple aggregation */
194  SCIP_Real* scalars; /**< multipliers a in multiple aggregation */
195  SCIP_VAR** vars; /**< variables y in multiple aggregation */
196  int nvars; /**< number of variables in aggregation */
197  int varssize; /**< size of vars and scalars arrays */
198 };
199 
200 /** negation information: x' = c - x */
202 {
203  SCIP_Real constant; /**< constant shift c in negation */
204 };
205 
206 /** variable of the problem */
207 struct SCIP_Var
208 {
209  SCIP_Real obj; /**< objective function value of variable (might be changed temporarily in probing mode)*/
210  SCIP_Real unchangedobj; /**< unchanged objective function value of variable (ignoring temporary changes in probing mode) */
211  SCIP_Real branchfactor; /**< factor to weigh variable's branching score with */
212  SCIP_Real rootsol; /**< last primal solution of variable in root node, or zero */
213  SCIP_Real bestrootsol; /**< best primal solution of variable in root node, or zero, w.r.t. root LP value and root reduced cost */
214  SCIP_Real bestrootredcost; /**< best reduced costs of variable in root node, or zero, w.r.t. root LP value and root solution value */
215  SCIP_Real bestrootlpobjval; /**< best root LP objective value, or SCIP_INVALID, w.r.t. root solution value and root reduced cost */
216  SCIP_Real relaxsol; /**< primal solution of variable in current relaxation solution, or SCIP_INVALID */
217  SCIP_Real nlpsol; /**< primal solution of variable in current NLP solution, or SCIP_INVALID */
218  SCIP_Real primsolavg; /**< weighted average of all values of variable in primal feasible solutions */
219  SCIP_Real conflictlb; /**< maximal lower bound of variable in the current conflict */
220  SCIP_Real conflictub; /**< minimal upper bound of variable in the current conflict */
221  SCIP_Real conflictrelaxedlb; /**< minimal relaxed lower bound of variable in the current conflict (conflictrelqxlb <= conflictlb) */
222  SCIP_Real conflictrelaxedub; /**< minimal release upper bound of variable in the current conflict (conflictrelqxlb <= conflictlb) */
223  SCIP_Real lazylb; /**< global lower bound that is ensured by constraints and has not to be added to the LP */
224  SCIP_Real lazyub; /**< global upper bound that is ensured by constraints and has not to be added to the LP */
225  SCIP_DOM glbdom; /**< domain of variable in global problem */
226  SCIP_DOM locdom; /**< domain of variable in current subproblem */
227  union
228  {
229  SCIP_ORIGINAL original; /**< original variable information */
230  SCIP_COL* col; /**< LP column (for column variables) */
231  SCIP_AGGREGATE aggregate; /**< aggregation information (for aggregated variables) */
232  SCIP_MULTAGGR multaggr; /**< multiple aggregation information (for multiple aggregated variables) */
233  SCIP_NEGATE negate; /**< negation information (for negated variables) */
234  } data;
235  char* name; /**< name of the variable */
236  SCIP_DECL_VARCOPY ((*varcopy)); /**< copies variable data if wanted to subscip, or NULL */
237  SCIP_DECL_VARDELORIG ((*vardelorig)); /**< frees user data of original variable */
238  SCIP_DECL_VARTRANS ((*vartrans)); /**< creates transformed user data by transforming original user data */
239  SCIP_DECL_VARDELTRANS ((*vardeltrans)); /**< frees user data of transformed variable */
240  SCIP_VARDATA* vardata; /**< user data for this specific variable */
241  SCIP_VAR** parentvars; /**< parent variables in the aggregation tree */
242  SCIP_VAR* negatedvar; /**< pointer to the variables negation: x' = lb + ub - x, or NULL if not created */
243  SCIP_VBOUNDS* vlbs; /**< variable lower bounds x >= b*y + d */
244  SCIP_VBOUNDS* vubs; /**< variable upper bounds x <= b*y + d */
245  SCIP_IMPLICS* implics; /**< implications y >=/<= b following from x <= 0 and x >= 1 (x binary), or NULL if x is not binary */
246  SCIP_CLIQUELIST* cliquelist; /**< list of cliques the variable and its negation is member of */
247  SCIP_EVENTFILTER* eventfilter; /**< event filter for events concerning this variable; not for ORIGINAL vars */
248  SCIP_BDCHGINFO* lbchginfos; /**< bound change informations for lower bound changes from root to current node */
249  SCIP_BDCHGINFO* ubchginfos; /**< bound change informations for upper bound changes from root to current node */
250  SCIP_HISTORY* history; /**< branching and inference history information */
251  SCIP_HISTORY* historycrun; /**< branching and inference history information for current run */
252  SCIP_VALUEHISTORY* valuehistory; /**< branching and inference history information which are value based, or NULL if not used */
253  SCIP_Longint closestvblpcount; /**< LP count for which the closestvlbidx/closestvubidx entries are valid */
254  int index; /**< consecutively numbered variable identifier */
255  int probindex; /**< array position in problems vars array, or -1 if not assigned to a problem */
256  int pseudocandindex; /**< array position in pseudo branching candidates array, or -1 */
257  int eventqueueindexobj; /**< array position in event queue of objective change event, or -1 */
258  int eventqueueindexlb; /**< array position in event queue of lower bound change event, or -1 */
259  int eventqueueindexub; /**< array position in event queue of upper bound change event, or -1 */
260  int parentvarssize; /**< available slots in parentvars array */
261  int nparentvars; /**< number of parent variables in aggregation tree (used slots of parentvars) */
262  int nuses; /**< number of times, this variable is referenced */
263  int nlocksdown[NLOCKTYPES]; /**< array of variable locks for rounding down; if zero, rounding down is always feasible */
264  int nlocksup[NLOCKTYPES]; /**< array of variable locks for rounding up; if zero, rounding up is always feasible */
265  int branchpriority; /**< priority of the variable for branching */
266  int lbchginfossize; /**< available slots in lbchginfos array */
267  int nlbchginfos; /**< number of lower bound changes from root node to current node */
268  int ubchginfossize; /**< available slots in ubchginfos array */
269  int nubchginfos; /**< number of upper bound changes from root node to current node */
270  int conflictlbcount; /**< number of last conflict, the lower bound was member of */
271  int conflictubcount; /**< number of last conflict, the upper bound was member of */
272  int closestvlbidx; /**< index of closest VLB variable in current LP solution, or -1 */
273  int closestvubidx; /**< index of closest VUB variable in current LP solution, or -1 */
274  unsigned int initial:1; /**< TRUE iff var's column should be present in the initial root LP */
275  unsigned int removable:1; /**< TRUE iff var's column is removable from the LP (due to aging or cleanup) */
276  unsigned int deletable:1; /**< TRUE iff the variable is removable from the problem */
277  unsigned int deleted:1; /**< TRUE iff variable was marked for deletion from the problem */
278  unsigned int donotaggr:1; /**< TRUE iff variable is not allowed to be aggregated */
279  unsigned int donotmultaggr:1; /**< TRUE iff variable is not allowed to be multi-aggregated */
280  unsigned int vartype:2; /**< type of variable: binary, integer, implicit integer, continuous */
281  unsigned int varstatus:3; /**< status of variable: original, loose, column, fixed, aggregated, multiaggregated, negated */
282  unsigned int pseudocostflag:2; /**< temporary flag used in pseudo cost update */
283  unsigned int branchdirection:2; /**< preferred branching direction of the variable (downwards, upwards, auto) */
284  unsigned int eventqueueimpl:1; /**< is an IMPLADDED event on this variable currently in the event queue? */
285  unsigned int delglobalstructs:1; /**< is variable marked to be removed from global structures (cliques etc.)? */
286  unsigned int relaxationonly:1; /**< TRUE if variable has been introduced only to define a relaxation */
287 #ifndef NDEBUG
288  SCIP* scip; /**< SCIP data structure */
289 #endif
290 };
291 
292 #ifdef __cplusplus
293 }
294 #endif
295 
296 #endif
SCIP_HOLELIST * holelist
Definition: struct_var.h:172
SCIP_BRANCHINGDATA branchingdata
Definition: struct_var.h:96
int nubchginfos
Definition: struct_var.h:269
SCIP_BDCHGIDX bdchgidx
Definition: struct_var.h:121
type definitions for implications, variable bounds, and cliques
SCIP_Real conflictlb
Definition: struct_var.h:219
unsigned int inferboundtype
Definition: struct_var.h:102
unsigned int relaxationonly
Definition: struct_var.h:286
char * name
Definition: struct_var.h:235
unsigned int boundchgtype
Definition: struct_var.h:123
int eventqueueindexub
Definition: struct_var.h:259
SCIP_HOLE hole
Definition: struct_var.h:60
SCIP_Real bestrootsol
Definition: struct_var.h:213
#define SCIP_DECL_VARTRANS(x)
Definition: type_var.h:151
SCIP_DOM origdom
Definition: struct_var.h:178
SCIP_BOUNDCHG * boundchgs
Definition: struct_var.h:134
SCIP_Real constant
Definition: struct_var.h:193
SCIP_Real bestrootredcost
Definition: struct_var.h:214
SCIP_HISTORY * historycrun
Definition: struct_var.h:251
SCIP_Longint closestvblpcount
Definition: struct_var.h:253
SCIP_DOMCHGBOTH domchgboth
Definition: struct_var.h:163
SCIP_BDCHGINFO * ubchginfos
Definition: struct_var.h:249
unsigned int nboundchgs
Definition: struct_var.h:132
SCIP_HOLELIST * newlist
Definition: struct_var.h:68
SCIP_Real right
Definition: struct_var.h:54
#define NLOCKTYPES
Definition: type_var.h:94
struct SCIP_VarData SCIP_VARDATA
Definition: type_var.h:120
struct SCIP_BranchingData SCIP_BRANCHINGDATA
Definition: type_var.h:109
SCIP_Real constant
Definition: struct_var.h:203
SCIP_INFERENCEDATA inferencedata
Definition: struct_var.h:120
SCIP_HOLELIST * oldlist
Definition: struct_var.h:69
unsigned int nboundchgs
Definition: struct_var.h:140
int nlbchginfos
Definition: struct_var.h:267
#define SCIP_DECL_VARCOPY(x)
Definition: type_var.h:194
int index
Definition: struct_var.h:254
SCIP_Real constant
Definition: struct_var.h:186
unsigned int domchgtype
Definition: struct_var.h:151
SCIP_HOLECHG * holechgs
Definition: struct_var.h:143
SCIP_Real obj
Definition: struct_var.h:209
unsigned int domchgtype
Definition: struct_var.h:133
SCIP_Real relaxsol
Definition: struct_var.h:216
int conflictlbcount
Definition: struct_var.h:270
SCIP_VAR ** vars
Definition: struct_var.h:195
int branchpriority
Definition: struct_var.h:265
SCIP_VAR * var
Definition: struct_var.h:187
#define SCIP_DECL_VARDELTRANS(x)
Definition: type_var.h:164
type definitions for LP management
int pseudocandindex
Definition: struct_var.h:256
SCIP_Real conflictrelaxedub
Definition: struct_var.h:222
unsigned int inferboundtype
Definition: struct_var.h:125
struct SCIP_InferenceData SCIP_INFERENCEDATA
Definition: type_var.h:110
SCIP_Real conflictrelaxedlb
Definition: struct_var.h:221
SCIP_AGGREGATE aggregate
Definition: struct_var.h:231
SCIP_Real lazylb
Definition: struct_var.h:223
SCIP_VBOUNDS * vlbs
Definition: struct_var.h:243
int lbchginfossize
Definition: struct_var.h:266
unsigned int varstatus
Definition: struct_var.h:281
SCIP_Real bestrootlpobjval
Definition: struct_var.h:215
SCIP_VARDATA * vardata
Definition: struct_var.h:240
SCIP_Real primsolavg
Definition: struct_var.h:218
SCIP_HOLECHG * holechgs
Definition: struct_var.h:153
unsigned int pos
Definition: struct_var.h:122
SCIP_VAR * transvar
Definition: struct_var.h:179
SCIP_DOMCHGDYN domchgdyn
Definition: struct_var.h:164
unsigned int initial
Definition: struct_var.h:274
SCIP_NEGATE negate
Definition: struct_var.h:233
int nparentvars
Definition: struct_var.h:261
SCIP_Real unchangedobj
Definition: struct_var.h:210
SCIP_VBOUNDS * vubs
Definition: struct_var.h:244
type definitions for problem variables
int eventqueueindexlb
Definition: struct_var.h:258
int closestvubidx
Definition: struct_var.h:273
unsigned int nboundchgs
Definition: struct_var.h:150
unsigned int branchdirection
Definition: struct_var.h:283
int ubchginfossize
Definition: struct_var.h:268
type definitions for managing events
unsigned int vartype
Definition: struct_var.h:280
unsigned int boundchgtype
Definition: struct_var.h:100
SCIP_VAR * var
Definition: struct_var.h:99
SCIP_INFERENCEDATA inferencedata
Definition: struct_var.h:97
SCIP_Real ub
Definition: struct_var.h:171
unsigned int boundtype
Definition: struct_var.h:101
unsigned int deletable
Definition: struct_var.h:276
SCIP_MULTAGGR multaggr
Definition: struct_var.h:232
unsigned int deleted
Definition: struct_var.h:277
unsigned int removable
Definition: struct_var.h:275
unsigned int domchgtype
Definition: struct_var.h:141
SCIP_Real conflictub
Definition: struct_var.h:220
unsigned int redundant
Definition: struct_var.h:104
SCIP_Real oldbound
Definition: struct_var.h:117
int closestvlbidx
Definition: struct_var.h:272
int nuses
Definition: struct_var.h:262
int probindex
Definition: struct_var.h:255
SCIP * scip
Definition: struct_var.h:288
SCIP_EVENTFILTER * eventfilter
Definition: struct_var.h:247
int conflictubcount
Definition: struct_var.h:271
SCIP_DOM locdom
Definition: struct_var.h:226
SCIP_VALUEHISTORY * valuehistory
Definition: struct_var.h:252
#define SCIP_DECL_VARDELORIG(x)
Definition: type_var.h:131
SCIP_Real newbound
Definition: struct_var.h:93
type definitions for propagators
SCIP_VAR ** parentvars
Definition: struct_var.h:241
SCIP_DOMCHGBOUND domchgbound
Definition: struct_var.h:162
SCIP_HOLELIST * next
Definition: struct_var.h:61
unsigned int boundtype
Definition: struct_var.h:124
unsigned int donotaggr
Definition: struct_var.h:278
SCIP_Real lazyub
Definition: struct_var.h:224
unsigned int redundant
Definition: struct_var.h:126
unsigned int pseudocostflag
Definition: struct_var.h:282
int eventqueueindexobj
Definition: struct_var.h:257
SCIP_VAR * var
Definition: struct_var.h:119
SCIP_Real * scalars
Definition: struct_var.h:194
SCIP_IMPLICS * implics
Definition: struct_var.h:245
#define SCIP_Real
Definition: def.h:186
type definitions for branching and inference history
unsigned int eventqueueimpl
Definition: struct_var.h:284
int parentvarssize
Definition: struct_var.h:260
SCIP_CLIQUELIST * cliquelist
Definition: struct_var.h:246
SCIP_Real branchfactor
Definition: struct_var.h:211
unsigned int donotmultaggr
Definition: struct_var.h:279
#define SCIP_Longint
Definition: def.h:171
SCIP_Real nlpsol
Definition: struct_var.h:217
SCIP_BOUNDCHG * boundchgs
Definition: struct_var.h:142
SCIP_Real lb
Definition: struct_var.h:170
SCIP_DOM glbdom
Definition: struct_var.h:225
SCIP_VAR * negatedvar
Definition: struct_var.h:242
SCIP_Real newbound
Definition: struct_var.h:118
unsigned int delglobalstructs
Definition: struct_var.h:285
SCIP_Real rootsol
Definition: struct_var.h:212
SCIP_HISTORY * history
Definition: struct_var.h:250
common defines and data types used in all packages of SCIP
SCIP_ORIGINAL original
Definition: struct_var.h:229
unsigned int applied
Definition: struct_var.h:103
SCIP_HOLELIST ** ptr
Definition: struct_var.h:67
SCIP_BOUNDCHG * boundchgs
Definition: struct_var.h:152
SCIP_COL * col
Definition: struct_var.h:230
SCIP_Real left
Definition: struct_var.h:53
type definitions for constraints and constraint handlers
SCIP_BDCHGINFO * lbchginfos
Definition: struct_var.h:248
SCIP_Real scalar
Definition: struct_var.h:185