Cgl
0.59.10
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Odd Hole Cut Generator Class. More...
#include <CglOddHole.hpp>
Public Member Functions | |
Generate Cuts | |
virtual void | generateCuts (const OsiSolverInterface &si, OsiCuts &cs, const CglTreeInfo info=CglTreeInfo()) |
Generate odd hole cuts for the model of the solver interface, si. More... | |
Create Row List | |
void | createRowList (const OsiSolverInterface &si, const int *possible=NULL) |
Create a list of rows which might yield cuts this is to speed up process The possible parameter is a list to cut down search. More... | |
void | createRowList (int numberRows, const int *whichRow) |
This version passes in a list - 1 marks possible. More... | |
Create Clique List | |
void | createCliqueList (int numberCliques, const int *cliqueStart, const int *cliqueMember) |
Create a list of extra row cliques which may not be in matrix At present these are classical cliques. More... | |
Number Possibilities | |
int | numberPossible () |
Returns how many rows might give odd hole cuts. More... | |
Gets and Sets | |
double | getMinimumViolation () const |
Minimum violation. More... | |
void | setMinimumViolation (double value) |
double | getMinimumViolationPer () const |
Minimum violation per entry. More... | |
void | setMinimumViolationPer (double value) |
int | getMaximumEntries () const |
Maximum number of entries in a cut. More... | |
void | setMaximumEntries (int value) |
Constructors and destructors | |
CglOddHole () | |
Default constructor. More... | |
CglOddHole (const CglOddHole &) | |
Copy constructor. More... | |
virtual CglCutGenerator * | clone () const |
Clone. More... | |
CglOddHole & | operator= (const CglOddHole &rhs) |
Assignment operator. More... | |
virtual | ~CglOddHole () |
Destructor. More... | |
virtual void | refreshSolver (OsiSolverInterface *solver) |
This can be used to refresh any inforamtion. More... | |
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CglCutGenerator () | |
Default constructor. More... | |
CglCutGenerator (const CglCutGenerator &) | |
Copy constructor. More... | |
CglCutGenerator & | operator= (const CglCutGenerator &rhs) |
Assignment operator. More... | |
virtual | ~CglCutGenerator () |
Destructor. More... | |
virtual std::string | generateCpp (FILE *) |
Create C++ lines to set the generator in the current state. More... | |
int | getAggressiveness () const |
Get Aggressiveness - 0 = neutral, 100 is normal root node. More... | |
void | setAggressiveness (int value) |
Set Aggressiveness - 0 = neutral, 100 is normal root node. More... | |
void | setGlobalCuts (bool trueOrFalse) |
Set whether can do global cuts. More... | |
bool | canDoGlobalCuts () const |
Say whether can do global cuts. More... | |
virtual bool | mayGenerateRowCutsInTree () const |
Returns true if may generate Row cuts in tree (rather than root node). More... | |
virtual bool | needsOptimalBasis () const |
Return true if needs optimal basis to do cuts. More... | |
virtual int | maximumLengthOfCutInTree () const |
Return maximum length of cut in tree. More... | |
Friends | |
void | CglOddHoleUnitTest (const OsiSolverInterface *siP, const std::string mpdDir) |
A function that tests the methods in the CglOddHole class. More... | |
Additional Inherited Members | |
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int | aggressive_ |
Aggressiveness - 0 = neutral, 100 is normal root node. More... | |
bool | canDoGlobalCuts_ |
True if can do global cuts i.e. no general integers. More... | |
Odd Hole Cut Generator Class.
Definition at line 14 of file CglOddHole.hpp.
CglOddHole::CglOddHole | ( | ) |
Default constructor.
CglOddHole::CglOddHole | ( | const CglOddHole & | ) |
Copy constructor.
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Destructor.
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Generate odd hole cuts for the model of the solver interface, si.
This looks at all rows of type sum x(i) <= 1 (or == 1) (x 0-1) and sees if there is an odd cycle cut. See Grotschel, Lovasz and Schrijver (1988) for method. This is then lifted by using the corresponding Chvatal cut i.e. Take all rows in cycle and add them together. RHS will be odd so weaken all odd coefficients so 1.0 goes to 0.0 etc - then constraint is sum even(j)*x(j) <= odd which can be replaced by sum (even(j)/2)*x(j) <= (odd-1.0)/2. A similar cut can be generated for sum x(i) >= 1.
Insert the generated cuts into OsiCut, cs.
This is only done for rows with unsatisfied 0-1 variables. If there are many of these it will be slow. Improvements would do a randomized subset and also speed up shortest path algorithm used.
Implements CglCutGenerator.
void CglOddHole::createRowList | ( | const OsiSolverInterface & | si, |
const int * | possible = NULL |
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Create a list of rows which might yield cuts this is to speed up process The possible parameter is a list to cut down search.
void CglOddHole::createRowList | ( | int | numberRows, |
const int * | whichRow | ||
) |
This version passes in a list - 1 marks possible.
void CglOddHole::createCliqueList | ( | int | numberCliques, |
const int * | cliqueStart, | ||
const int * | cliqueMember | ||
) |
Create a list of extra row cliques which may not be in matrix At present these are classical cliques.
int CglOddHole::numberPossible | ( | ) |
Returns how many rows might give odd hole cuts.
double CglOddHole::getMinimumViolation | ( | ) | const |
Minimum violation.
void CglOddHole::setMinimumViolation | ( | double | value | ) |
double CglOddHole::getMinimumViolationPer | ( | ) | const |
Minimum violation per entry.
void CglOddHole::setMinimumViolationPer | ( | double | value | ) |
int CglOddHole::getMaximumEntries | ( | ) | const |
Maximum number of entries in a cut.
void CglOddHole::setMaximumEntries | ( | int | value | ) |
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Clone.
Implements CglCutGenerator.
CglOddHole& CglOddHole::operator= | ( | const CglOddHole & | rhs | ) |
Assignment operator.
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virtual |
This can be used to refresh any inforamtion.
Reimplemented from CglCutGenerator.
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friend |
A function that tests the methods in the CglOddHole class.
The only reason for it not to be a member method is that this way it doesn't have to be compiled into the library. And that's a gain, because the library should be compiled with optimization on, but this method should be compiled with debugging.