Scippy

SCIP

Solving Constraint Integer Programs

struct_lp.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) 2002-2021 Konrad-Zuse-Zentrum */
7 /* fuer Informationstechnik Berlin */
8 /* */
9 /* SCIP is distributed under the terms of the ZIB Academic License. */
10 /* */
11 /* You should have received a copy of the ZIB Academic License */
12 /* along with SCIP; see the file COPYING. If not visit scipopt.org. */
13 /* */
14 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
15 
16 /**@file struct_lp.h
17  * @ingroup INTERNALAPI
18  * @brief data structures for LP management
19  * @author Tobias Achterberg
20  *
21  * In SCIP, the LP is defined as follows:
22  *
23  * min obj * x
24  * lhs <= A * x + const <= rhs
25  * lb <= x <= ub
26  *
27  * The row activities are defined as activity = A * x + const and must
28  * therefore be in the range of [lhs,rhs].
29  *
30  * Mathematically, each range constraint would account for two dual
31  * variables, one for each inequality. Since in an optimal solution (at
32  * least) one of them may be chosen to be zero, we may define one dual
33  * multiplier for each row as the difference of those two.
34  *
35  * Let y be the vector of dual multipliers for the rows, then the reduced
36  * costs are defined as
37  *
38  * redcost = obj - A^T * y.
39  *
40  * In an optimal solution, y must be
41  *
42  * - nonnegative, if the corresponding row activity is not tight at its rhs
43  * - nonpositive, if the corresponding row activity is not tight at its lhs
44  * - zero, if the corresponding row activity is not at any of its sides
45  *
46  * and the reduced costs must be
47  *
48  * - nonnegative, if the corresponding variable is not tight at its ub
49  * - nonpositive, if the corresponding variable is not tight at its lb
50  * - zero, if the corresponding variable is not at any of its bounds.
51  *
52  * The main datastructures for storing an LP are the rows and the columns.
53  * A row can live on its own (if it was created by a separator), or as SCIP_LP
54  * relaxation of a constraint. Thus, it has a nuses-counter, and is
55  * deleted, if not needed any more.
56  * A column cannot live on its own. It is always connected to a problem
57  * variable. Because pricing is always problem specific, it cannot create
58  * LP columns without introducing new variables. Thus, each column is
59  * connected to exactly one variable, and is deleted, if the variable
60  * is deleted.
61  */
62 
63 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
64 
65 #ifndef __SCIP_STRUCT_LP_H__
66 #define __SCIP_STRUCT_LP_H__
67 
68 
69 #include "scip/def.h"
70 #include "scip/type_lp.h"
71 #include "scip/type_var.h"
72 #include "scip/type_event.h"
73 #include "lpi/type_lpi.h"
74 
75 #ifdef __cplusplus
76 extern "C" {
77 #endif
78 
79 /** collected values of a column which depend on the LP solution
80  * We store these values in each column to recover the LP solution at start of diving or probing mode, say, without
81  * having to resolve the LP. Note that we do not store the farkascoef value since we do expect a node with infeasible
82  * LP to be pruned anyway.
83  */
85 {
86  SCIP_Real primsol; /**< primal solution value in LP, is 0 if col is not in LP */
87  SCIP_Real redcost; /**< reduced cost value in LP, or SCIP_INVALID if not yet calculated */
88  unsigned int basisstatus:2; /**< basis status of column in last LP solution, invalid for non-LP columns */
89 };
90 
91 /** collected values of a row which depend on the LP solution
92  * We store these values in each row to recover the LP solution at start of diving or probing mode, say, without having
93  * to resolve the LP. We do not store the dualfarkas value since we expect a node with infeasible LP to be pruned
94  * anyway. In this unlikely case, we have to resolve the LP.
95  */
97 {
98  SCIP_Real dualsol; /**< dual solution value in LP, is 0 if row is not in LP */
99  SCIP_Real activity; /**< row activity value in LP, or SCIP_INVALID if not yet calculated */
100  unsigned int basisstatus:2; /**< basis status of row in last LP solution, invalid for non-LP rows */
101 };
102 
103 /** collected values of the LP data which depend on the LP solution
104  * We store these values to recover the LP solution at start of diving or probing mode, say, without having to resolve
105  * the LP.
106  */
108 {
109  SCIP_LPSOLSTAT lpsolstat; /**< solution status of last LP solution */
110  SCIP_Real lpobjval; /**< objective value of LP without loose variables, or SCIP_INVALID */
111  SCIP_Bool primalfeasible; /**< is current LP solution primal feasible? */
112  SCIP_Bool primalchecked; /**< was current LP solution checked for primal feasibility? */
113  SCIP_Bool dualfeasible; /**< is current LP solution dual feasible? */
114  SCIP_Bool dualchecked; /**< was current LP solution checked for primal feasibility? */
115  SCIP_Bool solisbasic; /**< is current LP solution a basic solution? */
116  SCIP_Bool lpissolved; /**< is current LP solved? */
117 };
118 
119 /** LP column;
120  * The row vector of the LP column is partitioned into two parts: The first col->nlprows rows in the rows array
121  * are the ones that belong to the current LP (col->rows[j]->lppos >= 0) and that are linked to the column
122  * (col->linkpos[j] >= 0). The remaining col->len - col->nlprows rows in the rows array are the ones that
123  * don't belong to the current LP (col->rows[j]->lppos == -1) or that are not linked to the column
124  * (col->linkpos[j] == -1).
125  */
126 struct SCIP_Col
127 {
128  SCIP_Real obj; /**< current objective value of column in LP (might be changed in diving or probing) */
129  SCIP_Real lb; /**< current lower bound of column in LP */
130  SCIP_Real ub; /**< current upper bound of column in LP */
131  SCIP_Real unchangedobj; /**< unchanged objective value of column (ignoring diving or probing changes) */
132  SCIP_Real lazylb; /**< lazy lower bound of the column; if the current lower bound is not greater than
133  * the lazy lower bound, then the lower bound has not to be added to the LP */
134  SCIP_Real lazyub; /**< lazy upper bound of the column; if the current upper bound is not smaller than
135  * the lazy upper bound, then the upper bound has not to be added to the LP */
136  SCIP_Real flushedobj; /**< objective value of column already flushed to the LP solver */
137  SCIP_Real flushedlb; /**< lower bound of column already flushed to the LP solver */
138  SCIP_Real flushedub; /**< upper bound of column already flushed to the LP solver */
139  SCIP_Real primsol; /**< primal solution value in LP, is 0 if col is not in LP */
140  SCIP_Real redcost; /**< reduced cost value in LP, or SCIP_INVALID if not yet calculated */
141  SCIP_Real farkascoef; /**< coefficient in dual Farkas infeasibility proof (== dualfarkas^T A_c) */
142  SCIP_Real minprimsol; /**< minimal LP solution value, this column ever assumed */
143  SCIP_Real maxprimsol; /**< maximal LP solution value, this column ever assumed */
144  SCIP_Real sbdown; /**< strong branching information for downwards branching */
145  SCIP_Real sbup; /**< strong branching information for upwards branching */
146  SCIP_Real sbsolval; /**< LP solution value of column at last strong branching call */
147  SCIP_Real sblpobjval; /**< LP objective value at last strong branching call on the column */
148  SCIP_Longint sbnode; /**< node number of the last strong branching call on this column */
149  SCIP_Longint obsoletenode; /**< last node where this column was removed due to aging */
150  SCIP_COLSOLVALS* storedsolvals; /**< values stored before entering diving or probing mode */
151  SCIP_VAR* var; /**< variable, this column represents; there cannot be a column without variable */
152  SCIP_ROW** rows; /**< rows of column entries, that may have a nonzero dual solution value */
153  SCIP_Real* vals; /**< coefficients of column entries */
154  SCIP_Longint validredcostlp; /**< LP number for which reduced cost value is valid */
155  SCIP_Longint validfarkaslp; /**< LP number for which Farkas coefficient is valid */
156  SCIP_Longint validsblp; /**< LP number for which strong branching values are valid */
157  int* linkpos; /**< position of col in col vector of the row, or -1 if not yet linked */
158  int index; /**< consecutively numbered column identifier */
159  int size; /**< size of the row- and val-arrays */
160  int len; /**< number of nonzeros in column */
161  int nlprows; /**< number of linked rows in column, that belong to the current LP */
162  int nunlinked; /**< number of column entries, where the rows don't know about the column */
163  int lppos; /**< column position number in current LP, or -1 if not in current LP */
164  int lpipos; /**< column position number in LP solver, or -1 if not in LP solver */
165  int lpdepth; /**< depth level at which column entered the LP, or -1 if not in current LP */
166  int sbitlim; /**< strong branching iteration limit used to get strong branching values, or -1 */
167  int nsbcalls; /**< number of times, strong branching was applied on the column */
168  int age; /**< number of successive times this variable was in LP and was 0.0 in solution */
169  int var_probindex; /**< copy of var->probindex for avoiding expensive dereferencing */
170  unsigned int basisstatus:2; /**< basis status of column in last LP solution, invalid for non-LP columns */
171  unsigned int lprowssorted:1; /**< are the linked LP rows in the rows array sorted by non-decreasing index? */
172  unsigned int nonlprowssorted:1; /**< are the non-LP/not linked rows sorted by non-decreasing index? */
173  unsigned int objchanged:1; /**< has objective value changed, and has data of LP solver to be updated? */
174  unsigned int lbchanged:1; /**< has lower bound changed, and has data of LP solver to be updated? */
175  unsigned int ubchanged:1; /**< has upper bound changed, and has data of LP solver to be updated? */
176  unsigned int coefchanged:1; /**< has the coefficient vector changed, and has LP solver to be updated? */
177  unsigned int integral:1; /**< is associated variable of integral type? */
178  unsigned int removable:1; /**< is column removable from the LP (due to aging or cleanup)? */
179  unsigned int sbdownvalid:1; /**< stores whether the stored strong branching down value is a valid dual bound;
180  * otherwise, it can only be used as an estimate value */
181  unsigned int sbupvalid:1; /**< stores whether the stored strong branching up value is a valid dual bound;
182  * otherwise, it can only be used as an estimate value */
183 };
184 
185 /** LP row
186  * The column vector of the LP row is partitioned into two parts: The first row->nlpcols columns in the cols array
187  * are the ones that belong to the current LP (row->cols[j]->lppos >= 0) and that are linked to the row
188  * (row->linkpos[j] >= 0). The remaining row->len - row->nlpcols columns in the cols array are the ones that
189  * don't belong to the current LP (row->cols[j]->lppos == -1) or that are not linked to the row
190  * (row->linkpos[j] == -1).
191  */
192 struct SCIP_Row
193 {
194  SCIP_Real constant; /**< constant shift c in row lhs <= ax + c <= rhs */
195  SCIP_Real lhs; /**< left hand side of row */
196  SCIP_Real rhs; /**< right hand side of row */
197  SCIP_Real flushedlhs; /**< left hand side minus constant of row already flushed to the LP solver */
198  SCIP_Real flushedrhs; /**< right hand side minus constant of row already flushed to the LP solver */
199  SCIP_Real sqrnorm; /**< squared Euclidean norm of row vector */
200  SCIP_Real sumnorm; /**< sum norm of row vector (sum of absolute values of coefficients) */
201  SCIP_Real objprod; /**< scalar product of row vector with objective function */
202  SCIP_Real maxval; /**< maximal absolute value of row vector, only valid if nummaxval > 0 */
203  SCIP_Real minval; /**< minimal absolute non-zero value of row vector, only valid if numminval > 0 */
204  SCIP_Real dualsol; /**< dual solution value in LP, is 0 if row is not in LP */
205  SCIP_Real activity; /**< row activity value in LP, or SCIP_INVALID if not yet calculated */
206  SCIP_Real dualfarkas; /**< multiplier value in dual Farkas infeasibility proof */
207  SCIP_Real pseudoactivity; /**< row activity value in pseudo solution, or SCIP_INVALID if not yet calculated */
208  SCIP_Real minactivity; /**< minimal activity value w.r.t. the column's bounds, or SCIP_INVALID */
209  SCIP_Real maxactivity; /**< maximal activity value w.r.t. the column's bounds, or SCIP_INVALID */
210  SCIP_Longint validpsactivitydomchg; /**< domain change number for which pseudo activity value is valid */
211  SCIP_Longint validactivitybdsdomchg;/**< domain change number for which activity bound values are valid */
212  SCIP_Longint obsoletenode; /**< last node where this row was removed due to aging */
213  SCIP_Longint activeinlpcounter; /**< counter for the number of times this row was active in an optimal LP solution */
214  SCIP_Longint nlpsaftercreation; /**< counter for the number of LPs after the row has been created */
215  SCIP_ROWSOLVALS* storedsolvals; /**< values stored before entering diving or probing mode */
216  void* origin; /**< pointer to constraint handler or separator who created the row (NULL if unknown) */
217  char* name; /**< name of the row */
218  SCIP_COL** cols; /**< columns of row entries, that may have a nonzero primal solution value */
219  int* cols_index; /**< copy of cols[i]->index for avoiding expensive dereferencing */
220  SCIP_Real* vals; /**< coefficients of row entries */
221  int* linkpos; /**< position of row in row vector of the column, or -1 if not yet linked */
222  SCIP_EVENTFILTER* eventfilter; /**< event filter for events concerning this row */
223  SCIP_Longint validactivitylp; /**< LP number for which activity value is valid */
224  int index; /**< consecutively numbered row identifier */
225  int size; /**< size of the col- and val-arrays */
226  int len; /**< number of nonzeros in row */
227  int nlpcols; /**< number of linked columns in row, that belong to the current LP */
228  int nunlinked; /**< number of row entries, where the columns don't know about the row */
229  int nuses; /**< number of times, this row is referenced */
230  int lppos; /**< row position number in current LP, or -1 if not in current LP */
231  int lpipos; /**< row position number in LP solver, or -1 if not in LP solver */
232  int lpdepth; /**< depth level at which row entered the LP, or -1 if not in current LP */
233  int minidx; /**< minimal column index of row entries */
234  int maxidx; /**< maximal column index of row entries */
235  int numintcols; /**< number of integral columns */
236  int nummaxval; /**< number of coefs with absolute value equal to maxval, zero if maxval invalid */
237  int numminval; /**< number of coefs with absolute value equal to minval, zero if minval invalid */
238  int age; /**< number of successive times this row was in LP and was not sharp in solution */
239  int rank; /**< rank of the row (upper bound, to be precise) */
240  unsigned int basisstatus:2; /**< basis status of row in last LP solution, invalid for non-LP rows */
241  unsigned int lpcolssorted:1; /**< are the linked LP columns in the cols array sorted by non-decreasing index? */
242  unsigned int nonlpcolssorted:1; /**< are the non-LP/not linked columns sorted by non-decreasing index? */
243  unsigned int delaysort:1; /**< should the row sorting be delayed and done in a lazy fashion? */
244  unsigned int validminmaxidx:1; /**< are minimal and maximal column index valid? */
245  unsigned int lhschanged:1; /**< was left hand side or constant changed, and has LP solver to be updated? */
246  unsigned int rhschanged:1; /**< was right hand side or constant changed, and has LP solver to be updated? */
247  unsigned int coefchanged:1; /**< was the coefficient vector changed, and has LP solver to be updated? */
248  unsigned int integral:1; /**< is activity (without constant) of row always integral in feasible solution? */
249  unsigned int local:1; /**< is row only valid locally? */
250  unsigned int modifiable:1; /**< is row modifiable during node processing (subject to column generation)? */
251  unsigned int removable:1; /**< is row removable from the LP (due to aging or cleanup)? */
252  unsigned int inglobalcutpool:1; /**< is row contained in the global cut pool? */
253  unsigned int normunreliable:1; /**< is the objective product of the row unreliable? */
254  unsigned int nlocks:15; /**< number of sealed locks of an unmodifiable row */
255  unsigned int origintype:3; /**< origin of row (0: unknown, 1: constraint handler, 2: constraint, 3: separator, 4: reoptimization) */
256 };
257 
258 /** current LP data */
259 struct SCIP_Lp
260 {
261  SCIP_Real lpobjval; /**< objective value of LP without loose variables, or SCIP_INVALID */
262  SCIP_Real looseobjval; /**< current solution value of all loose variables set to their best bounds,
263  * ignoring variables, with infinite best bound */
264  SCIP_Real rellooseobjval; /**< last reliable solution value of all loose variables set to their best bounds,
265  * ignoring variables, with infinite best bound */
266  SCIP_Real glbpseudoobjval; /**< global pseudo solution value with all variables set to their best global bounds,
267  * ignoring variables, with infinite best bound */
268  SCIP_Real relglbpseudoobjval; /**< last reliable global pseudo solution value */
269  SCIP_Real pseudoobjval; /**< current pseudo solution value with all variables set to their best bounds,
270  * ignoring variables, with infinite best bound */
271  SCIP_Real relpseudoobjval; /**< last reliable pseudo solution value */
272  SCIP_Real rootlpobjval; /**< objective value of root LP without loose variables, or SCIP_INVALID */
273  SCIP_Real rootlooseobjval; /**< objective value of loose variables in root node, or SCIP_INVALID */
274  SCIP_Real cutoffbound; /**< upper objective limit of LP (copy of primal->cutoffbound) */
275  SCIP_Real feastol; /**< current feasibility tolerance */
276  SCIP_Real lpiobjlim; /**< current objective limit in LPI */
277  SCIP_Real lpifeastol; /**< current feasibility tolerance in LPI */
278  SCIP_Real lpidualfeastol; /**< current reduced costs feasibility tolerance in LPI */
279  SCIP_Real lpibarrierconvtol; /**< current convergence tolerance used in barrier algorithm in LPI */
280  SCIP_Real lpiconditionlimit; /**< current condition number limit in LPI */
281  SCIP_Real lpimarkowitz; /**< current markowitz threshold */
282  SCIP_Real objsqrnorm; /**< squared Euclidean norm of objective function vector of problem variables */
283  SCIP_Real objsumnorm; /**< sum norm of objective function vector of problem variables */
284  SCIP_Real degeneracy; /**< share of degenerate non-basic variables in the current LP */
285  SCIP_Real varconsratio; /**< variable-constraint ratio of the optimal face */
286  SCIP_LPI* lpi; /**< LP solver interface */
287  SCIP_COL** lpicols; /**< array with columns currently stored in the LP solver */
288  SCIP_ROW** lpirows; /**< array with rows currently stored in the LP solver */
289  SCIP_COL** chgcols; /**< array of changed columns not yet applied to the LP solver */
290  SCIP_ROW** chgrows; /**< array of changed rows not yet applied to the LP solver */
291  SCIP_COL** cols; /**< array with current LP columns in correct order */
292  SCIP_COL** lazycols; /**< array with current LP lazy columns */
293  SCIP_ROW** rows; /**< array with current LP rows in correct order */
294  SCIP_Real* soldirection; /**< normalized vector in direction of primal solution from current LP solution */
295  SCIP_LPISTATE* divelpistate; /**< stores LPI state (basis information) before diving starts */
296  SCIP_Real* divechgsides; /**< stores the lhs/rhs changed in the current diving */
297  SCIP_SIDETYPE* divechgsidetypes; /**< stores the side type of the changes done in the current diving */
298  SCIP_ROW** divechgrows; /**< stores the rows changed in the current diving */
299  SCIP_LPSOLVALS* storedsolvals; /**< collected values of the LP data which depend on the LP solution */
300  SCIP_SOL* validsoldirsol; /**< primal solution for which the currently stored solution direction vector is valid */
301  SCIP_Longint validsollp; /**< LP number for which the currently stored solution values are valid */
302  SCIP_Longint validfarkaslp; /**< LP number for which the currently stored Farkas row multipliers are valid */
303  SCIP_Longint validsoldirlp; /**< LP number for which the currently stored solution direction vector is valid */
304  SCIP_Longint validdegeneracylp; /**< LP number for which the currently stored degeneracy information is valid */
305  SCIP_Longint divenolddomchgs; /**< number of domain changes before diving has started */
306  int lpicolssize; /**< available slots in lpicols vector */
307  int nlpicols; /**< number of columns in the LP solver */
308  int lpifirstchgcol; /**< first column of the LP which differs from the column in the LP solver */
309  int lpirowssize; /**< available slots in lpirows vector */
310  int nlpirows; /**< number of rows in the LP solver */
311  int lpifirstchgrow; /**< first row of the LP which differs from the row in the LP solver */
312  int chgcolssize; /**< available slots in chgcols vector */
313  int nchgcols; /**< current number of chgcols (number of used slots in chgcols vector) */
314  int chgrowssize; /**< available slots in chgrows vector */
315  int nchgrows; /**< current number of chgrows (number of used slots in chgrows vector) */
316  int colssize; /**< available slots in cols vector */
317  int soldirectionsize; /**< available slots in soldirection vector */
318  int ncols; /**< current number of LP columns (number of used slots in cols vector) */
319  int lazycolssize; /**< available slots in lazycols vector */
320  int nlazycols; /**< current number of LP lazy columns (number of used slots in lazycols vector) */
321  int nremovablecols; /**< number of removable columns in the LP */
322  int firstnewcol; /**< first column added at the current node */
323  int rowssize; /**< available slots in rows vector */
324  int nrows; /**< current number of LP rows (number of used slots in rows vector) */
325  int nremovablerows; /**< number of removable rows in the LP */
326  int firstnewrow; /**< first row added at the current node */
327  int looseobjvalinf; /**< number of loose variables with infinite best bound in current solution */
328  int nloosevars; /**< number of loose variables in LP */
329  int glbpseudoobjvalinf; /**< number of variables with infinite best bound in global pseudo solution */
330  int pseudoobjvalinf; /**< number of variables with infinite best bound in current pseudo solution */
331  int ndivingrows; /**< number of rows when entering diving mode */
332  int ndivechgsides; /**< number of side changes in current diving */
333  int divechgsidessize; /**< size of the arrays */
334  int divinglpiitlim; /**< LPI iteration limit when entering diving mode */
335  int lpiitlim; /**< current iteration limit setting in LPI */
336  int lpifastmip; /**< current FASTMIP setting in LPI */
337  int lpithreads; /**< current THREADS setting in LPI */
338  int lpitiming; /**< current timing type in LPI */
339  int lpirandomseed; /**< current initial random seed in LPI */
340  int lpiscaling; /**< current SCALING setting in LPI */
341  int lpirefactorinterval;/**< current refactorization interval */
342  SCIP_PRICING lpipricing; /**< current pricing setting in LPI */
343  SCIP_LPSOLSTAT lpsolstat; /**< solution status of last LP solution */
344  SCIP_LPALGO lastlpalgo; /**< algorithm used for last LP solve */
345  SCIP_Bool objsqrnormunreliable;/**< is squared Euclidean norm of objective function vector of problem
346  * variables unreliable and need recalculation? */
347  SCIP_Bool lpisolutionpolishing;/**< LP solution polishing method (0: disabled, 1: enabled) */
348  SCIP_Bool looseobjvalid; /**< is the loose objective value valid or should it be recomputed from scratch? */
349  SCIP_Bool glbpseudoobjvalid; /**< is the global pseudo solution value valid or should it be recomputed from scratch? */
350  SCIP_Bool pseudoobjvalid; /**< is the pseudo solution value valid or should it be recomputed from scratch? */
351  SCIP_Bool flushdeletedcols; /**< have LPI-columns been deleted in the last lpFlush() call? */
352  SCIP_Bool flushaddedcols; /**< have LPI-columns been added in the last lpFlush() call? */
353  SCIP_Bool flushdeletedrows; /**< have LPI-rows been deleted in the last lpFlush() call? */
354  SCIP_Bool flushaddedrows; /**< have LPI-rows been added in the last lpFlush() call? */
355  SCIP_Bool updateintegrality; /**< does integrality information need to be updated? */
356  SCIP_Bool flushed; /**< are all cached changes applied to the LP solver? */
357  SCIP_Bool solved; /**< is current LP solved? */
358  SCIP_Bool primalfeasible; /**< is current LP solution (rather LPI state) primal feasible? */
359  SCIP_Bool primalchecked; /**< was current LP solution checked for primal feasibility?? */
360  SCIP_Bool dualfeasible; /**< is current LP solution (rather LPI state) dual feasible? */
361  SCIP_Bool dualchecked; /**< was current LP solution checked for primal feasibility?? */
362  SCIP_Bool solisbasic; /**< is current LP solution a basic solution? */
363  SCIP_Bool rootlpisrelax; /**< is root LP a relaxation of the problem and its solution value a valid global lower bound? */
364  SCIP_Bool isrelax; /**< is the current LP a relaxation of the problem for which it has been solved and its
365  * solution value a valid local lower bound? */
366  SCIP_Bool installing; /**< whether the solution process is in stalling */
367  SCIP_Bool strongbranching; /**< whether the lp is used for strong branching */
368  SCIP_Bool probing; /**< are we currently in probing mode? */
369  SCIP_Bool strongbranchprobing;/**< are we currently in probing mode for strong branching? */
370  SCIP_Bool diving; /**< LP is used for diving: col bounds and obj don't correspond to variables */
371  SCIP_Bool divingobjchg; /**< objective values were changed in diving or probing: LP objective is invalid */
372  SCIP_Bool divinglazyapplied; /**< lazy bounds were applied to the LP during diving */
373  SCIP_Bool resolvelperror; /**< an error occurred during resolving the LP after diving or probing */
374  SCIP_Bool adjustlpval; /**< does an infinite LP objective value has been adjusted so far? */
375  SCIP_Bool lpifromscratch; /**< current FROMSCRATCH setting in LPI */
376  SCIP_Bool lpipresolving; /**< current PRESOLVING setting in LPI */
377  SCIP_Bool lpilpinfo; /**< current LPINFO setting in LPI */
378  SCIP_Bool lpihasfeastol; /**< does the LPI support the FEASTOL parameter? */
379  SCIP_Bool lpihasdualfeastol; /**< does the LPI support the DUALFEASTOL parameter? */
380  SCIP_Bool lpihasbarrierconvtol;/**< does the LPI support the BARRIERCONVTOL parameter? */
381  SCIP_Bool lpihasfastmip; /**< does the LPI support the FASTMIP parameter? */
382  SCIP_Bool lpihasscaling; /**< does the LPI support the SCALING parameter? */
383  SCIP_Bool lpihaspresolving; /**< does the LPI support the PRESOLVING parameter? */
384  SCIP_Bool lpihasrowrep; /**< does the LPI support row representation of a simplex basis? */
385  SCIP_Bool lpihaspolishing; /**< does the LPI support solution polishing? */
386  SCIP_Bool lpihasrefactor; /**< does the LPI support changing the refactorization interval? */
387  SCIP_Real lpirowrepswitch; /**< simplex algorithm shall use row representation of the basis
388  * if number of rows divided by number of columns exceeds this value */
389  SCIP_Bool divelpwasprimfeas; /**< primal feasibility when diving started */
390  SCIP_Bool divelpwasprimchecked;/**< primal feasibility was checked when diving started */
391  SCIP_Bool divelpwasdualfeas; /**< dual feasibility when diving started */
392  SCIP_Bool divelpwasdualchecked;/**< dual feasibility was checked when diving started */
393 };
394 
395 #ifdef __cplusplus
396 }
397 #endif
398 
399 #endif
SCIP_Bool solisbasic
Definition: struct_lp.h:362
SCIP_Real lazyub
Definition: struct_lp.h:134
SCIP_Bool lpissolved
Definition: struct_lp.h:116
int nunlinked
Definition: struct_lp.h:228
int firstnewrow
Definition: struct_lp.h:326
SCIP_Real sbup
Definition: struct_lp.h:145
int nsbcalls
Definition: struct_lp.h:167
SCIP_Bool primalchecked
Definition: struct_lp.h:112
SCIP_Real maxactivity
Definition: struct_lp.h:209
SCIP_Real obj
Definition: struct_lp.h:128
SCIP_Bool lpihaspresolving
Definition: struct_lp.h:383
SCIP_Longint validdegeneracylp
Definition: struct_lp.h:304
void * origin
Definition: struct_lp.h:216
SCIP_EVENTFILTER * eventfilter
Definition: struct_lp.h:222
SCIP_Real farkascoef
Definition: struct_lp.h:141
unsigned int ubchanged
Definition: struct_lp.h:175
int nummaxval
Definition: struct_lp.h:236
SCIP_Longint validactivitylp
Definition: struct_lp.h:223
int lpifirstchgrow
Definition: struct_lp.h:311
enum SCIP_LPAlgo SCIP_LPALGO
Definition: type_lp.h:79
int * cols_index
Definition: struct_lp.h:219
int nremovablecols
Definition: struct_lp.h:321
SCIP_Bool primalfeasible
Definition: struct_lp.h:358
int nchgrows
Definition: struct_lp.h:315
char * name
Definition: struct_lp.h:217
int nlpicols
Definition: struct_lp.h:307
SCIP_Longint activeinlpcounter
Definition: struct_lp.h:213
SCIP_LPALGO lastlpalgo
Definition: struct_lp.h:344
unsigned int origintype
Definition: struct_lp.h:255
int lpdepth
Definition: struct_lp.h:232
SCIP_Real objsumnorm
Definition: struct_lp.h:283
SCIP_ROW ** chgrows
Definition: struct_lp.h:290
SCIP_COL ** chgcols
Definition: struct_lp.h:289
int rank
Definition: struct_lp.h:239
int rowssize
Definition: struct_lp.h:323
unsigned int nonlprowssorted
Definition: struct_lp.h:172
SCIP_COL ** cols
Definition: struct_lp.h:291
int nlpirows
Definition: struct_lp.h:310
unsigned int normunreliable
Definition: struct_lp.h:253
int soldirectionsize
Definition: struct_lp.h:317
SCIP_ROW ** rows
Definition: struct_lp.h:152
int lppos
Definition: struct_lp.h:163
SCIP_Real lazylb
Definition: struct_lp.h:132
int pseudoobjvalinf
Definition: struct_lp.h:330
int divinglpiitlim
Definition: struct_lp.h:334
SCIP_Bool solved
Definition: struct_lp.h:357
SCIP_Bool dualchecked
Definition: struct_lp.h:361
SCIP_Bool lpifromscratch
Definition: struct_lp.h:375
unsigned int basisstatus
Definition: struct_lp.h:240
SCIP_Real dualsol
Definition: struct_lp.h:98
SCIP_Real redcost
Definition: struct_lp.h:140
SCIP_Bool pseudoobjvalid
Definition: struct_lp.h:350
unsigned int sbdownvalid
Definition: struct_lp.h:179
unsigned int objchanged
Definition: struct_lp.h:173
unsigned int delaysort
Definition: struct_lp.h:243
unsigned int basisstatus
Definition: struct_lp.h:170
SCIP_Real lpidualfeastol
Definition: struct_lp.h:278
SCIP_Real sbsolval
Definition: struct_lp.h:146
SCIP_Real sumnorm
Definition: struct_lp.h:200
int lpifastmip
Definition: struct_lp.h:336
int index
Definition: struct_lp.h:158
SCIP_Real relpseudoobjval
Definition: struct_lp.h:271
SCIP_Real dualfarkas
Definition: struct_lp.h:206
SCIP_Real minprimsol
Definition: struct_lp.h:142
SCIP_Real pseudoobjval
Definition: struct_lp.h:269
SCIP_Bool diving
Definition: struct_lp.h:370
SCIP_Real rootlooseobjval
Definition: struct_lp.h:273
int firstnewcol
Definition: struct_lp.h:322
unsigned int coefchanged
Definition: struct_lp.h:176
unsigned int integral
Definition: struct_lp.h:248
int lpifirstchgcol
Definition: struct_lp.h:308
int index
Definition: struct_lp.h:224
unsigned int basisstatus
Definition: struct_lp.h:100
enum SCIP_LPSolStat SCIP_LPSOLSTAT
Definition: type_lp.h:42
enum SCIP_Pricing SCIP_PRICING
Definition: type_lpi.h:77
int looseobjvalinf
Definition: struct_lp.h:327
SCIP_Bool flushdeletedcols
Definition: struct_lp.h:351
unsigned int rhschanged
Definition: struct_lp.h:246
int nlpcols
Definition: struct_lp.h:227
SCIP_COL ** lpicols
Definition: struct_lp.h:287
unsigned int lprowssorted
Definition: struct_lp.h:171
int lazycolssize
Definition: struct_lp.h:319
SCIP_Real objprod
Definition: struct_lp.h:201
int colssize
Definition: struct_lp.h:316
SCIP_Bool objsqrnormunreliable
Definition: struct_lp.h:345
SCIP_Bool lpihasfastmip
Definition: struct_lp.h:381
SCIP_Bool divelpwasdualfeas
Definition: struct_lp.h:391
SCIP_Bool lpipresolving
Definition: struct_lp.h:376
int nremovablerows
Definition: struct_lp.h:325
SCIP_Bool primalchecked
Definition: struct_lp.h:359
SCIP_Bool strongbranching
Definition: struct_lp.h:367
SCIP_Bool dualfeasible
Definition: struct_lp.h:113
int lpithreads
Definition: struct_lp.h:337
int ndivechgsides
Definition: struct_lp.h:332
int * linkpos
Definition: struct_lp.h:221
type definitions for LP management
SCIP_Real * vals
Definition: struct_lp.h:220
unsigned int integral
Definition: struct_lp.h:177
int nloosevars
Definition: struct_lp.h:328
int lppos
Definition: struct_lp.h:230
int divechgsidessize
Definition: struct_lp.h:333
int * linkpos
Definition: struct_lp.h:157
SCIP_Bool rootlpisrelax
Definition: struct_lp.h:363
SCIP_Real flushedlb
Definition: struct_lp.h:137
int lpiitlim
Definition: struct_lp.h:335
SCIP_Real lb
Definition: struct_lp.h:129
SCIP_Real dualsol
Definition: struct_lp.h:204
SCIP_Real lpibarrierconvtol
Definition: struct_lp.h:279
int glbpseudoobjvalinf
Definition: struct_lp.h:329
SCIP_Real sbdown
Definition: struct_lp.h:144
int lpirefactorinterval
Definition: struct_lp.h:341
SCIP_ROW ** divechgrows
Definition: struct_lp.h:298
SCIP_Real lpirowrepswitch
Definition: struct_lp.h:387
SCIP_Bool installing
Definition: struct_lp.h:366
SCIP_Bool divelpwasdualchecked
Definition: struct_lp.h:392
SCIP_Real sqrnorm
Definition: struct_lp.h:199
SCIP_Bool lpilpinfo
Definition: struct_lp.h:377
SCIP_Real pseudoactivity
Definition: struct_lp.h:207
SCIP_PRICING lpipricing
Definition: struct_lp.h:342
SCIP_Bool dualchecked
Definition: struct_lp.h:114
SCIP_COL ** cols
Definition: struct_lp.h:218
SCIP_Bool adjustlpval
Definition: struct_lp.h:374
SCIP_Real minval
Definition: struct_lp.h:203
SCIP_Real flushedub
Definition: struct_lp.h:138
SCIP_ROW ** lpirows
Definition: struct_lp.h:288
unsigned int sbupvalid
Definition: struct_lp.h:181
SCIP_Longint validsoldirlp
Definition: struct_lp.h:303
SCIP_Longint validfarkaslp
Definition: struct_lp.h:302
SCIP_Longint validactivitybdsdomchg
Definition: struct_lp.h:211
SCIP_Real lhs
Definition: struct_lp.h:195
int nuses
Definition: struct_lp.h:229
int lpiscaling
Definition: struct_lp.h:340
type definitions for specific LP solvers interface
SCIP_Real cutoffbound
Definition: struct_lp.h:274
SCIP_Bool isrelax
Definition: struct_lp.h:364
int numintcols
Definition: struct_lp.h:235
int maxidx
Definition: struct_lp.h:234
SCIP_LPSOLVALS * storedsolvals
Definition: struct_lp.h:299
SCIP_Bool looseobjvalid
Definition: struct_lp.h:348
SCIP_Real activity
Definition: struct_lp.h:99
int lpirandomseed
Definition: struct_lp.h:339
type definitions for problem variables
SCIP_Longint nlpsaftercreation
Definition: struct_lp.h:214
SCIP_Bool flushaddedrows
Definition: struct_lp.h:354
SCIP_Bool resolvelperror
Definition: struct_lp.h:373
unsigned int removable
Definition: struct_lp.h:178
int lpicolssize
Definition: struct_lp.h:306
SCIP_LPI * lpi
Definition: struct_lp.h:286
SCIP_Real glbpseudoobjval
Definition: struct_lp.h:266
type definitions for managing events
SCIP_Bool lpihasfeastol
Definition: struct_lp.h:378
SCIP_SIDETYPE * divechgsidetypes
Definition: struct_lp.h:297
int var_probindex
Definition: struct_lp.h:169
SCIP_Real sblpobjval
Definition: struct_lp.h:147
int nchgcols
Definition: struct_lp.h:313
int len
Definition: struct_lp.h:160
SCIP_Real * soldirection
Definition: struct_lp.h:294
#define SCIP_Bool
Definition: def.h:70
SCIP_Real redcost
Definition: struct_lp.h:87
int numminval
Definition: struct_lp.h:237
int lpipos
Definition: struct_lp.h:231
int size
Definition: struct_lp.h:225
unsigned int modifiable
Definition: struct_lp.h:250
int chgrowssize
Definition: struct_lp.h:314
SCIP_Longint validfarkaslp
Definition: struct_lp.h:155
unsigned int lbchanged
Definition: struct_lp.h:174
SCIP_Bool divingobjchg
Definition: struct_lp.h:371
SCIP_Longint sbnode
Definition: struct_lp.h:148
SCIP_Real feastol
Definition: struct_lp.h:275
unsigned int basisstatus
Definition: struct_lp.h:88
SCIP_Real degeneracy
Definition: struct_lp.h:284
SCIP_Bool updateintegrality
Definition: struct_lp.h:355
SCIP_Bool lpihasdualfeastol
Definition: struct_lp.h:379
SCIP_Real unchangedobj
Definition: struct_lp.h:131
SCIP_Bool lpihaspolishing
Definition: struct_lp.h:385
int minidx
Definition: struct_lp.h:233
SCIP_Bool divelpwasprimchecked
Definition: struct_lp.h:390
int nlprows
Definition: struct_lp.h:161
SCIP_Bool lpihasscaling
Definition: struct_lp.h:382
unsigned int lpcolssorted
Definition: struct_lp.h:241
SCIP_Bool divinglazyapplied
Definition: struct_lp.h:372
SCIP_Longint validsollp
Definition: struct_lp.h:301
SCIP_Real ub
Definition: struct_lp.h:130
SCIP_ROW ** rows
Definition: struct_lp.h:293
SCIP_SOL * validsoldirsol
Definition: struct_lp.h:300
SCIP_Longint validredcostlp
Definition: struct_lp.h:154
SCIP_LPISTATE * divelpistate
Definition: struct_lp.h:295
SCIP_Real flushedrhs
Definition: struct_lp.h:198
SCIP_Real maxval
Definition: struct_lp.h:202
SCIP_Real minactivity
Definition: struct_lp.h:208
SCIP_Bool lpihasrefactor
Definition: struct_lp.h:386
SCIP_Real rhs
Definition: struct_lp.h:196
SCIP_Real constant
Definition: struct_lp.h:194
unsigned int removable
Definition: struct_lp.h:251
unsigned int lhschanged
Definition: struct_lp.h:245
SCIP_COL ** lazycols
Definition: struct_lp.h:292
SCIP_Real relglbpseudoobjval
Definition: struct_lp.h:268
int sbitlim
Definition: struct_lp.h:166
SCIP_Real lpimarkowitz
Definition: struct_lp.h:281
int age
Definition: struct_lp.h:168
SCIP_Longint validpsactivitydomchg
Definition: struct_lp.h:210
SCIP_COLSOLVALS * storedsolvals
Definition: struct_lp.h:150
SCIP_Real * vals
Definition: struct_lp.h:153
SCIP_Bool strongbranchprobing
Definition: struct_lp.h:369
SCIP_Real rellooseobjval
Definition: struct_lp.h:264
SCIP_LPSOLSTAT lpsolstat
Definition: struct_lp.h:109
SCIP_Bool lpihasbarrierconvtol
Definition: struct_lp.h:380
int lpipos
Definition: struct_lp.h:164
int chgcolssize
Definition: struct_lp.h:312
int lpitiming
Definition: struct_lp.h:338
SCIP_ROWSOLVALS * storedsolvals
Definition: struct_lp.h:215
SCIP_Real * divechgsides
Definition: struct_lp.h:296
SCIP_Real rootlpobjval
Definition: struct_lp.h:272
unsigned int coefchanged
Definition: struct_lp.h:247
SCIP_Bool flushed
Definition: struct_lp.h:356
int lpdepth
Definition: struct_lp.h:165
unsigned int inglobalcutpool
Definition: struct_lp.h:252
int nrows
Definition: struct_lp.h:324
SCIP_Bool divelpwasprimfeas
Definition: struct_lp.h:389
int ndivingrows
Definition: struct_lp.h:331
SCIP_Longint divenolddomchgs
Definition: struct_lp.h:305
SCIP_Real lpobjval
Definition: struct_lp.h:261
SCIP_Real primsol
Definition: struct_lp.h:86
#define SCIP_Real
Definition: def.h:163
SCIP_Bool solisbasic
Definition: struct_lp.h:115
SCIP_Real flushedobj
Definition: struct_lp.h:136
int size
Definition: struct_lp.h:159
SCIP_Longint validsblp
Definition: struct_lp.h:156
SCIP_Real lpiobjlim
Definition: struct_lp.h:276
int lpirowssize
Definition: struct_lp.h:309
int nunlinked
Definition: struct_lp.h:162
SCIP_Real primsol
Definition: struct_lp.h:139
SCIP_Real maxprimsol
Definition: struct_lp.h:143
#define SCIP_Longint
Definition: def.h:148
SCIP_Real varconsratio
Definition: struct_lp.h:285
SCIP_Bool lpisolutionpolishing
Definition: struct_lp.h:347
SCIP_VAR * var
Definition: struct_lp.h:151
int nlazycols
Definition: struct_lp.h:320
SCIP_Bool dualfeasible
Definition: struct_lp.h:360
unsigned int nlocks
Definition: struct_lp.h:254
SCIP_Longint obsoletenode
Definition: struct_lp.h:149
SCIP_Longint obsoletenode
Definition: struct_lp.h:212
common defines and data types used in all packages of SCIP
SCIP_Real lpifeastol
Definition: struct_lp.h:277
SCIP_Bool primalfeasible
Definition: struct_lp.h:111
unsigned int validminmaxidx
Definition: struct_lp.h:244
SCIP_LPSOLSTAT lpsolstat
Definition: struct_lp.h:343
unsigned int nonlpcolssorted
Definition: struct_lp.h:242
SCIP_Bool flushaddedcols
Definition: struct_lp.h:352
SCIP_Bool glbpseudoobjvalid
Definition: struct_lp.h:349
int ncols
Definition: struct_lp.h:318
SCIP_Real lpobjval
Definition: struct_lp.h:110
SCIP_Real objsqrnorm
Definition: struct_lp.h:282
unsigned int local
Definition: struct_lp.h:249
SCIP_Real activity
Definition: struct_lp.h:205
SCIP_Bool probing
Definition: struct_lp.h:368
SCIP_Bool flushdeletedrows
Definition: struct_lp.h:353
SCIP_Real looseobjval
Definition: struct_lp.h:262
int len
Definition: struct_lp.h:226
int age
Definition: struct_lp.h:238
SCIP_Bool lpihasrowrep
Definition: struct_lp.h:384
SCIP_Real flushedlhs
Definition: struct_lp.h:197
SCIP_Real lpiconditionlimit
Definition: struct_lp.h:280
enum SCIP_SideType SCIP_SIDETYPE
Definition: type_lp.h:58