OsiSolverBranch.hpp

// Copyright (C) 2005, International Business Machines
// Corporation and others.  All Rights Reserved.
// This code is licensed under the terms of the Eclipse Public License (EPL).

#ifndef OsiSolverBranch_H
#define OsiSolverBranch_H

class OsiSolverInterface;
#include "CoinWarmStartBasis.hpp"

//#############################################################################

/** Solver Branch Class

    This provides information on a branch as a set of tighter bounds on both ways
*/

class OsiSolverBranch {

public:
  ///@name Add and Get methods
  //@{
  /// Add a simple branch (i.e. first sets ub of floor(value), second lb of ceil(value))
  void addBranch(int iColumn, double value);

  /// Add bounds - way =-1 is first , +1 is second
  void addBranch(int way, int numberTighterLower, const int *whichLower, const double *newLower,
    int numberTighterUpper, const int *whichUpper, const double *newUpper);
  /// Add bounds - way =-1 is first , +1 is second
  void addBranch(int way, int numberColumns, const double *oldLower, const double *newLower,
    const double *oldUpper, const double *newUpper);

  /// Apply bounds
  void applyBounds(OsiSolverInterface &solver, int way) const;
  /// Returns true if current solution satsifies one side of branch
  bool feasibleOneWay(const OsiSolverInterface &solver) const;
  /// Starts
  inline const int *starts() const
  {
    return start_;
  }
  /// Which variables
  inline const int *which() const
  {
    return indices_;
  }
  /// Bounds
  inline const double *bounds() const
  {
    return bound_;
  }
  //@}

  ///@name Constructors and destructors
  //@{
  /// Default Constructor
  OsiSolverBranch();

  /// Copy constructor
  OsiSolverBranch(const OsiSolverBranch &rhs);

  /// Assignment operator
  OsiSolverBranch &operator=(const OsiSolverBranch &rhs);

  /// Destructor
  ~OsiSolverBranch();

  //@}

private:
  ///@name Private member data
  //@{
  /// Start of lower first, upper first, lower second, upper second
  int start_[5];
  /// Column numbers (if >= numberColumns treat as rows)
  int *indices_;
  /// New bounds
  double *bound_;
  //@}
};
//#############################################################################

/** Solver Result Class

    This provides information on a result as a set of tighter bounds on both ways
*/

class OsiSolverResult {

public:
  ///@name Add and Get methods
  //@{
  /// Create result
  void createResult(const OsiSolverInterface &solver, const double *lowerBefore,
    const double *upperBefore);

  /// Restore result
  void restoreResult(OsiSolverInterface &solver) const;

  /// Get basis
  inline const CoinWarmStartBasis &basis() const
  {
    return basis_;
  }

  /// Objective value (as minimization)
  inline double objectiveValue() const
  {
    return objectiveValue_;
  }

  /// Primal solution
  inline const double *primalSolution() const
  {
    return primalSolution_;
  }

  /// Dual solution
  inline const double *dualSolution() const
  {
    return dualSolution_;
  }

  /// Extra fixed
  inline const OsiSolverBranch &fixed() const
  {
    return fixed_;
  }
  //@}

  ///@name Constructors and destructors
  //@{
  /// Default Constructor
  OsiSolverResult();

  /// Constructor from solver
  OsiSolverResult(const OsiSolverInterface &solver, const double *lowerBefore,
    const double *upperBefore);

  /// Copy constructor
  OsiSolverResult(const OsiSolverResult &rhs);

  /// Assignment operator
  OsiSolverResult &operator=(const OsiSolverResult &rhs);

  /// Destructor
  ~OsiSolverResult();

  //@}

private:
  ///@name Private member data
  //@{
  /// Value of objective (if >= OsiSolverInterface::getInfinity() then infeasible)
  double objectiveValue_;
  /// Warm start information
  CoinWarmStartBasis basis_;
  /// Primal solution (numberColumns)
  double *primalSolution_;
  /// Dual solution (numberRows)
  double *dualSolution_;
  /// Which extra variables have been fixed (only way==-1 counts)
  OsiSolverBranch fixed_;
  //@}
};
#endif

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