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Diffstat (limited to 'thirdparty/linux/include/coin/CbcBranchCut.hpp')
| -rw-r--r-- | thirdparty/linux/include/coin/CbcBranchCut.hpp | 183 |
1 files changed, 183 insertions, 0 deletions
diff --git a/thirdparty/linux/include/coin/CbcBranchCut.hpp b/thirdparty/linux/include/coin/CbcBranchCut.hpp new file mode 100644 index 0000000..0fdc940 --- /dev/null +++ b/thirdparty/linux/include/coin/CbcBranchCut.hpp @@ -0,0 +1,183 @@ +/* $Id: CbcBranchCut.hpp 1573 2011-01-05 01:12:36Z lou $ */ +// Copyright (C) 2004, International Business Machines +// Corporation and others. All Rights Reserved. +// This code is licensed under the terms of the Eclipse Public License (EPL). + +#ifndef CbcBranchCut_H +#define CbcBranchCut_H + +#include "CbcBranchBase.hpp" +#include "OsiRowCut.hpp" +#include "CoinPackedMatrix.hpp" + +/** Define a cut branching class. + At present empty - all stuff in descendants +*/ + +class CbcBranchCut : public CbcObject { + +public: + + // Default Constructor + CbcBranchCut (); + + /** In to maintain normal methods + */ + CbcBranchCut (CbcModel * model); + // Copy constructor + CbcBranchCut ( const CbcBranchCut &); + + /// Clone + virtual CbcObject * clone() const; + + // Assignment operator + CbcBranchCut & operator=( const CbcBranchCut& rhs); + + // Destructor + ~CbcBranchCut (); + + /// Infeasibility + virtual double infeasibility(const OsiBranchingInformation * info, + int &preferredWay) const; + + using CbcObject::feasibleRegion ; + /** Set bounds to contain the current solution. + + More precisely, for the variable associated with this object, take the + value given in the current solution, force it within the current bounds + if required, then set the bounds to fix the variable at the integer + nearest the solution value. + + At present this will do nothing + */ + virtual void feasibleRegion(); + + /** \brief Return true if branch created by object should fix variables + */ + virtual bool boundBranch() const ; + + /// Creates a branching object + virtual CbcBranchingObject * createCbcBranch(OsiSolverInterface * solver, const OsiBranchingInformation * info, int way) ; + + /** \brief Given a valid solution (with reduced costs, etc.), + return a branching object which would give a new feasible + point in the good direction. + + The preferred branching object will force the variable to be +/-1 from + its current value, depending on the reduced cost and objective sense. If + movement in the direction which improves the objective is impossible due + to bounds on the variable, the branching object will move in the other + direction. If no movement is possible, the method returns NULL. + + Only the bounds on this variable are considered when determining if the new + point is feasible. + + At present this does nothing + */ + virtual CbcBranchingObject * preferredNewFeasible() const; + + /** \brief Given a valid solution (with reduced costs, etc.), + return a branching object which would give a new feasible + point in a bad direction. + + As for preferredNewFeasible(), but the preferred branching object will + force movement in a direction that degrades the objective. + + At present this does nothing + */ + virtual CbcBranchingObject * notPreferredNewFeasible() const ; + + using CbcObject::resetBounds ; + /** Reset original upper and lower bound values from the solver. + + Handy for updating bounds held in this object after bounds held in the + solver have been tightened. + */ + virtual void resetBounds(); + + +protected: + /// data + +}; +/** Cut branching object + + This object can specify a two-way branch in terms of two cuts +*/ + +class CbcCutBranchingObject : public CbcBranchingObject { + +public: + + /// Default constructor + CbcCutBranchingObject (); + + /** Create a cut branching object + + Cut down will applied on way=-1, up on way==1 + Assumed down will be first so way_ set to -1 + */ + CbcCutBranchingObject (CbcModel * model, OsiRowCut & down, OsiRowCut &up, bool canFix); + + /// Copy constructor + CbcCutBranchingObject ( const CbcCutBranchingObject &); + + /// Assignment operator + CbcCutBranchingObject & operator= (const CbcCutBranchingObject& rhs); + + /// Clone + virtual CbcBranchingObject * clone() const; + + /// Destructor + virtual ~CbcCutBranchingObject (); + + using CbcBranchingObject::branch ; + /** \brief Sets the bounds for variables or adds a cut depending on the + current arm of the branch and advances the object state to the next arm. + Returns change in guessed objective on next branch + */ + virtual double branch(); + + using CbcBranchingObject::print ; + /** \brief Print something about branch - only if log level high + */ + virtual void print(); + + /** \brief Return true if branch should fix variables + */ + virtual bool boundBranch() const; + + /** Return the type (an integer identifier) of \c this */ + virtual CbcBranchObjType type() const { + return CutBranchingObj; + } + + /** Compare the original object of \c this with the original object of \c + brObj. Assumes that there is an ordering of the original objects. + This method should be invoked only if \c this and brObj are of the same + type. + Return negative/0/positive depending on whether \c this is + smaller/same/larger than the argument. + */ + virtual int compareOriginalObject(const CbcBranchingObject* brObj) const; + + /** Compare the \c this with \c brObj. \c this and \c brObj must be os the + same type and must have the same original object, but they may have + different feasible regions. + Return the appropriate CbcRangeCompare value (first argument being the + sub/superset if that's the case). In case of overlap (and if \c + replaceIfOverlap is true) replace the current branching object with one + whose feasible region is the overlap. + */ + virtual CbcRangeCompare compareBranchingObject + (const CbcBranchingObject* brObj, const bool replaceIfOverlap = false); + +protected: + /// Cut for the down arm (way_ = -1) + OsiRowCut down_; + /// Cut for the up arm (way_ = 1) + OsiRowCut up_; + /// True if one way can fix variables + bool canFix_; +}; +#endif |