SCIP
Solving Constraint Integer Programs
Solving Constraint Integer Programs
methods for presolving
Definition in file presolve.c.
#include "scip/mem.h"#include "scip/presolve.h"#include "scip/prob.h"#include "scip/tree.h"#include "scip/solve.h"#include "scip/struct_scip.h"Go to the source code of this file.
Macros | |
| #define | CLEARRATIO 0.8 |
Functions | |
| static void | collectNonBinaryVBoundData (SCIP *scip, SCIP_VAR *var, int varidx, int pos, int nredvars, SCIP_Real *bounds, SCIP_Bool *boundtypes, SCIP_Real *newbounds, int *counts, int *countnonzeros, int *ncountnonzeros, int *issetvar, int nvars, int *foundbin, int *foundnonbin, int *implidx, int *nimplidx, SCIP_Real *lastbounds) |
| static void | collectNonBinaryImplicationData (SCIP *scip, SCIP_VAR *var, int varidx, int pos, int nredvars, SCIP_Bool value, SCIP_Real *bounds, SCIP_Bool *boundtypes, SCIP_Real *newbounds, int *counts, int *countnonzeros, int *ncountnonzeros, int *issetvar, int nvars, int *foundbin, int *foundnonbin, int *implidx, int *nimplidx, SCIP_Real *lastbounds) |
| static void | collectBinaryCliqueData (SCIP_VAR *var, int varidx, int pos, int nredvars, SCIP_Bool value, SCIP_Real *bounds, SCIP_Bool *boundtypes, SCIP_Real *newbounds, int *counts, int *countnonzeros, int *ncountnonzeros, int *issetvar, int nvars, int *foundbin, int *implidx, int *nimplidx) |
| SCIP_RETCODE | SCIPshrinkDisjunctiveVarSet (SCIP *scip, SCIP_VAR **vars, SCIP_Real *bounds, SCIP_Bool *boundtypes, SCIP_Bool *redundants, int nvars, int *nredvars, int *nglobalred, SCIP_Bool *setredundant, SCIP_Bool *glbinfeas, SCIP_Bool fullshortening) |
| #define CLEARRATIO 0.8 |
Definition at line 946 of file presolve.c.
Referenced by SCIPshrinkDisjunctiveVarSet().
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static |
collect variable bound information for a variable set reduction and global implication; only variable which have the vartype != SCIP_VARTYPE_BINARY have variable bounds
| scip | SCIP data structure |
| var | set variable |
| varidx | for lower bound set variable index, for upper bound set variable index
|
| pos | variables's position in bdchinfos |
| nredvars | number of reduced variables so far |
| bounds | array of bounds where one of them must be fullfilled |
| boundtypes | array of bound types |
| newbounds | array of implied bounds(, size is two times number of variables, first half for implied lower bounds, second for implied upper bounds) |
| counts | array of number of implication on a bound (, size is two times number of variables, first half for implied lower bounds, second for implied upper bounds) |
| countnonzeros | array to store the indices of non-zero entries in the counts array |
| ncountnonzeros | pointer to store the number of non-zero entries in the counts array |
| issetvar | array containing for set variables the position in the current set, or 0 if it is not a set variable or -1, if it is a redundant(i.e. implies another set variable) set variables(, size is two times number of variables, first half for implied lower bounds, second for implied upper bounds) |
| nvars | number of problem variables |
| foundbin | pointer to store the lowest index of a binary implication variable when found |
| foundnonbin | pointer to store the lowest index of a non-binary implication variable when found |
| implidx | array to store the variable indices (for upper bound 'nvars' is added to the index) which are implied |
| nimplidx | pointer to store the number of implied variables |
| lastbounds | array to remember last implied bounds before taken the current variable into account, first nvars for lower bound, second nvars for upper bound |
this array is used when a set variable got redundant, because it implies another set variable, and we need to correct the counts array
Definition at line 40 of file presolve.c.
References SCIP_INVALID, SCIP_Real, SCIP_VARTYPE_BINARY, SCIPdebugMsg, SCIPisFeasEQ(), SCIPisFeasGT(), SCIPisFeasLT(), SCIPisZero(), SCIPvarGetLbGlobal(), SCIPvarGetName(), SCIPvarGetNVlbs(), SCIPvarGetNVubs(), SCIPvarGetProbindex(), SCIPvarGetType(), SCIPvarGetUbGlobal(), SCIPvarGetVlbCoefs(), SCIPvarGetVlbConstants(), SCIPvarGetVlbVars(), SCIPvarGetVubCoefs(), SCIPvarGetVubConstants(), SCIPvarGetVubVars(), and SCIPvarIsBinary().
Referenced by SCIPshrinkDisjunctiveVarSet().
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static |
collect non-binary implication data for variable set reduction and global bound implications; only variable which have the vartype SCIP_VARTYPE_BINARY have implications, otherwise the implications are saved as variable bounds
| scip | SCIP data structure |
| var | set variable |
| varidx | for lower bound set variable index, for upper bound set variable index + number of variables |
| pos | variables's position in bdchinfos |
| nredvars | number of reduced variables so far |
| value | value used for clique and implication info |
| bounds | array of bounds where one of them must be fullfilled |
| boundtypes | array of bound types |
| newbounds | array of implied bounds(, size is two times number of variables, first half for implied lower bounds, second for implied upper bounds) |
| counts | array of number of implication on a bound (, size is two times number of variables, first half for implied lower bounds, second for implied upper bounds) |
| countnonzeros | array to store the indices of non-zero entries in the counts array |
| ncountnonzeros | pointer to store the number of non-zero entries in the counts array |
| issetvar | array containing for set variables the position in the current set, or 0 if it is not a set variable or -1, if it is a redundant(i.e. implies another set variable) set variables(, size is two times number of variables, first half for implied lower bounds, second for implied upper bounds) |
| nvars | number of problem variables |
| foundbin | pointer to store the lowest index of a binary implication variable when found |
| foundnonbin | pointer to store the lowest index of a non-binary implication variable when found |
| implidx | array to store the variable indices (for upper bound 'nvars' is added to the index) which are implied |
| nimplidx | pointer to store the number of implied variables |
| lastbounds | array to remember last implied bounds before taken the current variable into account, first nvars for lower bound, second nvars for upper bound |
this array is used when a set variable got redundant, because it implies another set variable, and we need to correct the counts array
Definition at line 579 of file presolve.c.
References SCIP_BOUNDTYPE_UPPER, SCIP_INVALID, SCIP_Real, SCIP_VARTYPE_BINARY, SCIPdebugMsg, SCIPisFeasEQ(), SCIPisFeasGE(), SCIPisFeasLE(), SCIPvarGetImplBounds(), SCIPvarGetImplTypes(), SCIPvarGetImplVars(), SCIPvarGetLbGlobal(), SCIPvarGetName(), SCIPvarGetNImpls(), SCIPvarGetProbindex(), SCIPvarGetType(), SCIPvarGetUbGlobal(), and SCIPvarIsBinary().
Referenced by SCIPshrinkDisjunctiveVarSet().
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static |
collect clique data on binary variables for variable set reduction and global bound implications
| var | set variable |
| varidx | for lower bound set variable index, for upper bound set variable index
|
| pos | variables's position in bdchinfos |
| nredvars | number of reduced variables so far |
| value | value used for clique and implication info |
| bounds | array of bounds where one of them must be fullfilled |
| boundtypes | array of bound types |
| newbounds | array of implied bounds(, size is two times number of variables, first half for implied lower bounds, second for implied upper bounds) |
| counts | array of number of implication on a bound (, size is two times number of variables, first half for implied lower bounds, second for implied upper bounds) |
| countnonzeros | array to store the indices of non-zero entries in the counts array |
| ncountnonzeros | pointer to store the number of non-zero entries in the counts array |
| issetvar | array containing for set variables the position in the current set, or 0 if it is not a set variable, or -1, if it is a redundant (i.e. implies another set variable) set variable (the size of the array is two times the number of variables, first half for implied lower bounds, second for implied upper bounds) |
| nvars | number of problem variables |
| foundbin | pointer to store the lowest index of a binary implication variable when found |
| implidx | array to store the variable indices (for upper bound 'nvars' is added to the index) which are implied |
| nimplidx | pointer to store the number of implied variables |
Definition at line 807 of file presolve.c.
References SCIP_Bool, SCIPcliqueGetNVars(), SCIPcliqueGetValues(), SCIPcliqueGetVars(), SCIPdebugMessage, SCIPvarGetCliques(), SCIPvarGetLbGlobal(), SCIPvarGetName(), SCIPvarGetNCliques(), SCIPvarGetProbindex(), SCIPvarGetUbGlobal(), and SCIPvarIsBinary().
Referenced by SCIPshrinkDisjunctiveVarSet().