//----------------------------------------------------------------------------- // name: OSI Interface for GLPK //----------------------------------------------------------------------------- // Copyright (C) 2001, Vivian De Smedt, Braden Hunsaker // Copyright (C) 2003 University of Pittsburgh // University of Pittsburgh coding done by Brady Hunsaker // All Rights Reserved. // This code is licensed under the terms of the Eclipse Public License (EPL). #ifndef OsiGlpkSolverInterface_H #define OsiGlpkSolverInterface_H #include #include "OsiSolverInterface.hpp" #include "CoinPackedMatrix.hpp" #include "CoinWarmStartBasis.hpp" #include "OsiGlpkConfig.h" /** GPLK Solver Interface Instantiation of OsiGlpkSolverInterface for GPLK */ #ifndef LPX #define LPX glp_prob #endif typedef struct glp_prob glp_prob; class OSIGLPKLIB_EXPORT OsiGlpkSolverInterface : virtual public OsiSolverInterface { friend void OsiGlpkSolverInterfaceUnitTest(const std::string &mpsDir, const std::string &netlibDir); public: //--------------------------------------------------------------------------- /**@name Solve methods */ //@{ /// Solve initial LP relaxation virtual void initialSolve(); /// Resolve an LP relaxation after problem modification virtual void resolve(); /// Invoke solver's built-in enumeration algorithm virtual void branchAndBound(); //@} //--------------------------------------------------------------------------- /**@name Parameter set/get methods The set methods return true if the parameter was set to the given value, false otherwise. There can be various reasons for failure: the given parameter is not applicable for the solver (e.g., refactorization frequency for the volume algorithm), the parameter is not yet implemented for the solver or simply the value of the parameter is out of the range the solver accepts. If a parameter setting call returns false check the details of your solver. The get methods return true if the given parameter is applicable for the solver and is implemented. In this case the value of the parameter is returned in the second argument. Otherwise they return false. */ //@{ // Set an integer parameter bool setIntParam(OsiIntParam key, int value); // Set an double parameter bool setDblParam(OsiDblParam key, double value); // Set a string parameter bool setStrParam(OsiStrParam key, const std::string &value); // Set a hint parameter bool setHintParam(OsiHintParam key, bool sense = true, OsiHintStrength strength = OsiHintTry, void *info = 0); // Get an integer parameter bool getIntParam(OsiIntParam key, int &value) const; // Get an double parameter bool getDblParam(OsiDblParam key, double &value) const; // Get a string parameter bool getStrParam(OsiStrParam key, std::string &value) const; //@} //--------------------------------------------------------------------------- ///@name Methods returning info on how the solution process terminated //@{ /// Are there a numerical difficulties? virtual bool isAbandoned() const; /// Is optimality proven? virtual bool isProvenOptimal() const; /// Is primal infeasiblity proven? virtual bool isProvenPrimalInfeasible() const; /// Is dual infeasiblity proven? virtual bool isProvenDualInfeasible() const; /// Is the given primal objective limit reached? virtual bool isPrimalObjectiveLimitReached() const; /// Is the given dual objective limit reached? virtual bool isDualObjectiveLimitReached() const; /// Iteration limit reached? virtual bool isIterationLimitReached() const; /// Time limit reached? virtual bool isTimeLimitReached() const; /// (Integer) Feasible solution found? virtual bool isFeasible() const; //@} //--------------------------------------------------------------------------- /**@name WarmStart related methods */ //@{ /*! \brief Get an empty warm start object This routine returns an empty CoinWarmStartBasis object. Its purpose is to provide a way to give a client a warm start basis object of the appropriate type, which can resized and modified as desired. */ inline CoinWarmStart *getEmptyWarmStart() const { return (dynamic_cast< CoinWarmStart * >(new CoinWarmStartBasis())); } /// Get warmstarting information virtual CoinWarmStart *getWarmStart() const; /** Set warmstarting information. Return true/false depending on whether the warmstart information was accepted or not. */ virtual bool setWarmStart(const CoinWarmStart *warmstart); //@} //--------------------------------------------------------------------------- /**@name Hotstart related methods (primarily used in strong branching).
The user can create a hotstart (a snapshot) of the optimization process then reoptimize over and over again always starting from there.
NOTE: between hotstarted optimizations only bound changes are allowed. */ //@{ /// Create a hotstart point of the optimization process virtual void markHotStart(); /// Optimize starting from the hotstart virtual void solveFromHotStart(); /// Delete the snapshot virtual void unmarkHotStart(); //@} //--------------------------------------------------------------------------- /**@name Problem information methods These methods call the solver's query routines to return information about the problem referred to by the current object. Querying a problem that has no data associated with it result in zeros for the number of rows and columns, and NULL pointers from the methods that return vectors. Const pointers returned from any data-query method are valid as long as the data is unchanged and the solver is not called. */ //@{ /**@name Methods related to querying the input data */ //@{ /// Get number of columns virtual int getNumCols() const; /// Get number of rows virtual int getNumRows() const; /// Get number of nonzero elements virtual CoinBigIndex getNumElements() const; /// Get pointer to array[getNumCols()] of column lower bounds virtual const double *getColLower() const; /// Get pointer to array[getNumCols()] of column upper bounds virtual const double *getColUpper() const; /** Get pointer to array[getNumRows()] of row constraint senses. */ virtual const char *getRowSense() const; /** Get pointer to array[getNumRows()] of rows right-hand sides */ virtual const double *getRightHandSide() const; /** Get pointer to array[getNumRows()] of row ranges. */ virtual const double *getRowRange() const; /// Get pointer to array[getNumRows()] of row lower bounds virtual const double *getRowLower() const; /// Get pointer to array[getNumRows()] of row upper bounds virtual const double *getRowUpper() const; /// Get pointer to array[getNumCols()] of objective function coefficients virtual const double *getObjCoefficients() const; /// Get objective function sense (1 for min (default), -1 for max) virtual double getObjSense() const; /// Return true if column is continuous virtual bool isContinuous(int colNumber) const; #if 0 /// Return true if column is binary virtual bool isBinary(int columnNumber) const; /** Return true if column is integer. Note: This function returns true if the the column is binary or a general integer. */ virtual bool isInteger(int columnNumber) const; /// Return true if column is general integer virtual bool isIntegerNonBinary(int columnNumber) const; /// Return true if column is binary and not fixed at either bound virtual bool isFreeBinary(int columnNumber) const; #endif /// Get pointer to row-wise copy of matrix virtual const CoinPackedMatrix *getMatrixByRow() const; /// Get pointer to column-wise copy of matrix virtual const CoinPackedMatrix *getMatrixByCol() const; /// Get solver's value for infinity virtual double getInfinity() const; //@} /**@name Methods related to querying the solution */ //@{ /// Get pointer to array[getNumCols()] of primal solution vector virtual const double *getColSolution() const; /// Get pointer to array[getNumRows()] of dual prices virtual const double *getRowPrice() const; /// Get a pointer to array[getNumCols()] of reduced costs virtual const double *getReducedCost() const; /** Get pointer to array[getNumRows()] of row activity levels (constraint matrix times the solution vector */ virtual const double *getRowActivity() const; /// Get objective function value virtual double getObjValue() const; /** Get how many iterations it took to solve the problem (whatever "iteration" mean to the solver. */ virtual int getIterationCount() const; /** Get as many dual rays as the solver can provide. (In case of proven primal infeasibility there should be at least one.) NOTE for implementers of solver interfaces:
The double pointers in the vector should point to arrays of length getNumRows() and they should be allocated via new[].
NOTE for users of solver interfaces:
It is the user's responsibility to free the double pointers in the vector using delete[]. */ virtual std::vector< double * > getDualRays(int maxNumRays, bool fullRay = false) const; /** Get as many primal rays as the solver can provide. (In case of proven dual infeasibility there should be at least one.) The first getNumRows() ray components will always be associated with the row duals (as returned by getRowPrice()). If \c fullRay is true, the final getNumCols() entries will correspond to the ray components associated with the nonbasic variables. If the full ray is requested and the method cannot provide it, it will throw an exception. NOTE for implementers of solver interfaces:
The double pointers in the vector should point to arrays of length getNumCols() and they should be allocated via new[].
NOTE for users of solver interfaces:
It is the user's responsibility to free the double pointers in the vector using delete[]. */ virtual std::vector< double * > getPrimalRays(int maxNumRays) const; #if 0 /** Get vector of indices of solution which are integer variables presently at fractional values */ virtual OsiVectorInt getFractionalIndices(const double etol=1.e-05) const; #endif //@} //@} //--------------------------------------------------------------------------- /**@name Problem modifying methods */ //@{ //------------------------------------------------------------------------- /**@name Changing bounds on variables and constraints */ //@{ /** Set an objective function coefficient */ virtual void setObjCoeff(int elementIndex, double elementValue); using OsiSolverInterface::setColLower; /** Set a single column lower bound
Use -COIN_DBL_MAX for -infinity. */ virtual void setColLower(int elementIndex, double elementValue); using OsiSolverInterface::setColUpper; /** Set a single column upper bound
Use COIN_DBL_MAX for infinity. */ virtual void setColUpper(int elementIndex, double elementValue); /** Set a single column lower and upper bound
The default implementation just invokes setColLower() and setColUpper() */ virtual void setColBounds(int elementIndex, double lower, double upper); /** Set the bounds on a number of columns simultaneously
The default implementation just invokes setColLower() and setColUpper() over and over again. @param indexFirst,indexLast pointers to the beginning and after the end of the array of the indices of the variables whose either bound changes @param boundList the new lower/upper bound pairs for the variables */ virtual void setColSetBounds(const int *indexFirst, const int *indexLast, const double *boundList); /** Set a single row lower bound
Use -COIN_DBL_MAX for -infinity. */ virtual void setRowLower(int elementIndex, double elementValue); /** Set a single row upper bound
Use COIN_DBL_MAX for infinity. */ virtual void setRowUpper(int elementIndex, double elementValue); /** Set a single row lower and upper bound
The default implementation just invokes setRowLower() and setRowUpper() */ virtual void setRowBounds(int elementIndex, double lower, double upper); /** Set the type of a single row
*/ virtual void setRowType(int index, char sense, double rightHandSide, double range); /** Set the bounds on a number of rows simultaneously
The default implementation just invokes setRowLower() and setRowUpper() over and over again. @param indexFirst,indexLast pointers to the beginning and after the end of the array of the indices of the constraints whose either bound changes @param boundList the new lower/upper bound pairs for the constraints */ virtual void setRowSetBounds(const int *indexFirst, const int *indexLast, const double *boundList); /** Set the type of a number of rows simultaneously
The default implementation just invokes setRowType() over and over again. @param indexFirst,indexLast pointers to the beginning and after the end of the array of the indices of the constraints whose any characteristics changes @param senseList the new senses @param rhsList the new right hand sides @param rangeList the new ranges */ virtual void setRowSetTypes(const int *indexFirst, const int *indexLast, const char *senseList, const double *rhsList, const double *rangeList); //@} //------------------------------------------------------------------------- /**@name Integrality related changing methods */ //@{ /** Set the index-th variable to be a continuous variable */ virtual void setContinuous(int index); /** Set the index-th variable to be an integer variable */ virtual void setInteger(int index); /** Set the variables listed in indices (which is of length len) to be continuous variables */ virtual void setContinuous(const int *indices, int len); /** Set the variables listed in indices (which is of length len) to be integer variables */ virtual void setInteger(const int *indices, int len); //@} //------------------------------------------------------------------------- /// Set objective function sense (1 for min (default), -1 for max,) virtual void setObjSense(double s); /** Set the primal solution column values colsol[numcols()] is an array of values of the problem column variables. These values are copied to memory owned by the solver object or the solver. They will be returned as the result of colsol() until changed by another call to setColsol() or by a call to any solver routine. Whether the solver makes use of the solution in any way is solver-dependent. */ virtual void setColSolution(const double *colsol); /** Set dual solution vector rowprice[numrows()] is an array of values of the problem row dual variables. These values are copied to memory owned by the solver object or the solver. They will be returned as the result of rowprice() until changed by another call to setRowprice() or by a call to any solver routine. Whether the solver makes use of the solution in any way is solver-dependent. */ virtual void setRowPrice(const double *rowprice); //------------------------------------------------------------------------- /**@name Methods to expand a problem.
Note that if a column is added then by default it will correspond to a continuous variable. */ //@{ using OsiSolverInterface::addCol; /** */ virtual void addCol(const CoinPackedVectorBase &vec, const double collb, const double colub, const double obj); using OsiSolverInterface::addCols; /** */ virtual void addCols(const int numcols, const CoinPackedVectorBase *const *cols, const double *collb, const double *colub, const double *obj); /** */ virtual void deleteCols(const int num, const int *colIndices); using OsiSolverInterface::addRow; /** */ virtual void addRow(const CoinPackedVectorBase &vec, const double rowlb, const double rowub); /** */ virtual void addRow(const CoinPackedVectorBase &vec, const char rowsen, const double rowrhs, const double rowrng); using OsiSolverInterface::addRows; /** */ virtual void addRows(const int numrows, const CoinPackedVectorBase *const *rows, const double *rowlb, const double *rowub); /** */ virtual void addRows(const int numrows, const CoinPackedVectorBase *const *rows, const char *rowsen, const double *rowrhs, const double *rowrng); /** */ virtual void deleteRows(const int num, const int *rowIndices); #if 0 // ??? implemented in OsiSolverInterface //----------------------------------------------------------------------- /** Apply a collection of cuts.
Only cuts which have an effectiveness >= effectivenessLb are applied. */ virtual ApplyCutsReturnCode applyCuts(const OsiCuts & cs, double effectivenessLb = 0.0); #endif //@} //@} //--------------------------------------------------------------------------- /**@name Methods to input a problem */ //@{ /** Load in an problem by copying the arguments (the constraints on the rows are given by lower and upper bounds). If a pointer is 0 then the following values are the default: */ virtual void loadProblem(const CoinPackedMatrix &matrix, const double *collb, const double *colub, const double *obj, const double *rowlb, const double *rowub); /** Load in an problem by assuming ownership of the arguments (the constraints on the rows are given by lower and upper bounds). For default values see the previous method.
WARNING: The arguments passed to this method will be freed using the C++ delete and delete[] functions. */ virtual void assignProblem(CoinPackedMatrix *&matrix, double *&collb, double *&colub, double *&obj, double *&rowlb, double *&rowub); /** Load in an problem by copying the arguments (the constraints on the rows are given by sense/rhs/range triplets). If a pointer is 0 then the following values are the default: */ virtual void loadProblem(const CoinPackedMatrix &matrix, const double *collb, const double *colub, const double *obj, const char *rowsen, const double *rowrhs, const double *rowrng); /** Load in an problem by assuming ownership of the arguments (the constraints on the rows are given by sense/rhs/range triplets). For default values see the previous method.
WARNING: The arguments passed to this method will be freed using the C++ delete and delete[] functions. */ virtual void assignProblem(CoinPackedMatrix *&matrix, double *&collb, double *&colub, double *&obj, char *&rowsen, double *&rowrhs, double *&rowrng); /** Just like the other loadProblem() methods except that the matrix is given in a standard column major ordered format (without gaps). */ virtual void loadProblem(const int numcols, const int numrows, const CoinBigIndex *start, const int *index, const double *value, const double *collb, const double *colub, const double *obj, const double *rowlb, const double *rowub); /** Just like the other loadProblem() methods except that the matrix is given in a standard column major ordered format (without gaps). */ virtual void loadProblem(const int numcols, const int numrows, const CoinBigIndex *start, const int *index, const double *value, const double *collb, const double *colub, const double *obj, const char *rowsen, const double *rowrhs, const double *rowrng); using OsiSolverInterface::readMps; /** Read an mps file from the given filename */ virtual int readMps(const char *filename, const char *extension = "mps"); /** Write the problem into an mps file of the given filename. If objSense is non zero then -1.0 forces the code to write a maximization objective and +1.0 to write a minimization one. If 0.0 then solver can do what it wants */ virtual void writeMps(const char *filename, const char *extension = "mps", double objSense = 0.0) const; //@} //--------------------------------------------------------------------------- /*! \name Methods for row and column names. Only the set methods need to be overridden to ensure consistent names between OsiGlpk and the OSI base class. */ //@{ /*! \brief Set the objective function name */ void setObjName(std::string name); /*! \brief Set a row name Quietly does nothing if the name discipline (#OsiNameDiscipline) is auto. Quietly fails if the row index is invalid. */ void setRowName(int ndx, std::string name); /*! \brief Set a column name Quietly does nothing if the name discipline (#OsiNameDiscipline) is auto. Quietly fails if the column index is invalid. */ void setColName(int ndx, std::string name); //@} //--------------------------------------------------------------------------- /**@name GLPK specific public interfaces */ //@{ enum keepCachedFlag { /// discard all cached data (default) KEEPCACHED_NONE = 0, /// column information: objective values, lower and upper bounds, variable types KEEPCACHED_COLUMN = 1, /// row information: right hand sides, ranges and senses, lower and upper bounds for row KEEPCACHED_ROW = 2, /// problem matrix: matrix ordered by column and by row KEEPCACHED_MATRIX = 4, /// LP solution: primal and dual solution, reduced costs, row activities KEEPCACHED_RESULTS = 8, /// only discard cached LP solution KEEPCACHED_PROBLEM = KEEPCACHED_COLUMN | KEEPCACHED_ROW | KEEPCACHED_MATRIX, /// keep all cached data (similar to getMutableLpPtr()) KEEPCACHED_ALL = KEEPCACHED_PROBLEM | KEEPCACHED_RESULTS, /// free only cached column and LP solution information FREECACHED_COLUMN = KEEPCACHED_PROBLEM & ~KEEPCACHED_COLUMN, /// free only cached row and LP solution information FREECACHED_ROW = KEEPCACHED_PROBLEM & ~KEEPCACHED_ROW, /// free only cached matrix and LP solution information FREECACHED_MATRIX = KEEPCACHED_PROBLEM & ~KEEPCACHED_MATRIX, /// free only cached LP solution information FREECACHED_RESULTS = KEEPCACHED_ALL & ~KEEPCACHED_RESULTS }; /// Get pointer to GLPK model LPX *getModelPtr(); //@} /**@name Static instance counter methods */ //@{ /** GLPK has a context which must be freed after all GLPK LPs (or MIPs) are freed. * It is automatically created when the first LP is created. This method: */ static void incrementInstanceCounter() { ++numInstances_; } /** GLPK has a context which must be freed after all GLPK LPs (or MIPs) are freed. This method: */ static void decrementInstanceCounter(); /// Return the number of LP/MIP instances of instantiated objects using the GLPK environment. static unsigned int getNumInstances() { return numInstances_; } //@} /**@name Constructors and destructor */ //@{ /// Default Constructor OsiGlpkSolverInterface(); /// Clone virtual OsiSolverInterface *clone(bool copyData = true) const; /// Copy constructor OsiGlpkSolverInterface(const OsiGlpkSolverInterface &); /// Assignment operator OsiGlpkSolverInterface &operator=(const OsiGlpkSolverInterface &rhs); /// Destructor virtual ~OsiGlpkSolverInterface(); /// Resets as if default constructor virtual void reset(); //@} protected: /**@name Protected methods */ //@{ /// Apply a row cut. Return true if cut was applied. virtual void applyRowCut(const OsiRowCut &rc); /** Apply a column cut (bound adjustment). Return true if cut was applied. */ virtual void applyColCut(const OsiColCut &cc); /// Pointer to the model LPX *getMutableModelPtr() const; //@} private: /**@name Private methods */ //@{ /// The real work of a copy constructor (used by copy and assignment) void gutsOfCopy(const OsiGlpkSolverInterface &source); /// The real work of the constructor void gutsOfConstructor(); /// The real work of the destructor void gutsOfDestructor(); /// free cached column rim vectors void freeCachedColRim(); /// free cached row rim vectors void freeCachedRowRim(); /// free cached result vectors void freeCachedResults(); /// free cached matrices void freeCachedMatrix(); /// free all cached data (except specified entries, see getLpPtr()) void freeCachedData(int keepCached = KEEPCACHED_NONE); /// free all allocated memory void freeAllMemory(); /// Just for testing purposes void printBounds(); /// Fill cached collumn bounds void fillColBounds() const; //@} /**@name Private member data */ //@{ /// GLPK model represented by this class instance mutable LPX *lp_; /// GLPK simplex solver control parameters. Opaque to the client. void *smcp_ ; /// GLPK branch-and-cut control parameters. Opaque to the client. void *iocp_ ; /// number of GLPK instances currently in use (counts only those created by OsiGlpk) static unsigned int numInstances_; // Remember whether simplex or b&b was most recently done // 0 = simplex; 1 = b&b int bbWasLast_; // Int parameters. /// simplex iteration limit (per call to solver) int maxIteration_; /// simplex iteration limit (for hot start) int hotStartMaxIteration_; /// OSI name discipline int nameDisc_; /// Scaling setting int scaleFlags_ ; // Double parameters. /// dual objective limit (measure of badness; stop if we're worse) double dualObjectiveLimit_; /// primal objective limit (measure of goodness; stop if we're better) double primalObjectiveLimit_; /// dual feasibility tolerance double dualTolerance_; /// primal feasibility tolerance double primalTolerance_; /// constant offset for objective function double objOffset_; // String parameters /// Problem name std::string probName_; /*! \brief Array for info blocks associated with hints. */ mutable void *info_[OsiLastHintParam]; /// Hotstart information /// size of column status and value arrays int hotStartCStatSize_; /// column status array int *hotStartCStat_; /// primal variable values double *hotStartCVal_; /// dual variable values double *hotStartCDualVal_; /// size of row status and value arrays int hotStartRStatSize_; /// row status array int *hotStartRStat_; /// row slack values double *hotStartRVal_; /// row dual values double *hotStartRDualVal_; // Status information /// glpk stopped on iteration limit bool isIterationLimitReached_; /// glpk stopped on time limit bool isTimeLimitReached_; /// glpk abandoned the problem bool isAbandoned_; /*! \brief glpk stopped on lower objective limit When minimising, this is the primal limit; when maximising, the dual limit. */ bool isObjLowerLimitReached_; /*! \brief glpk stopped on upper objective limit When minimising, this is the dual limit; when maximising, the primal limit. */ bool isObjUpperLimitReached_; /// glpk declared the problem primal infeasible bool isPrimInfeasible_; /// glpk declared the problem dual infeasible bool isDualInfeasible_; /// glpk declared the problem feasible bool isFeasible_; /**@name Cached information derived from the GLPK model */ //@{ /// Number of iterations mutable int iter_used_; /// Pointer to objective vector mutable double *obj_; /// Pointer to dense vector of variable lower bounds mutable double *collower_; /// Pointer to dense vector of variable lower bounds mutable double *colupper_; /// Pointer to dense vector of variable types (continous, binary, integer) mutable char *ctype_; /// Pointer to dense vector of row sense indicators mutable char *rowsense_; /// Pointer to dense vector of row right-hand side values mutable double *rhs_; /// Pointer to dense vector of slack upper bounds for range constraints (undefined for non-range rows) mutable double *rowrange_; /// Pointer to dense vector of row lower bounds mutable double *rowlower_; /// Pointer to dense vector of row upper bounds mutable double *rowupper_; /// Pointer to primal solution vector mutable double *colsol_; /// Pointer to dual solution vector mutable double *rowsol_; /// Pointer to reduced cost vector mutable double *redcost_; /// Pointer to row activity (slack) vector mutable double *rowact_; /// Pointer to row-wise copy of problem matrix coefficients. mutable CoinPackedMatrix *matrixByRow_; /// Pointer to row-wise copy of problem matrix coefficients. mutable CoinPackedMatrix *matrixByCol_; //@} //@} }; #endif // OsiGlpkSolverInterface_H /* vi: softtabstop=2 shiftwidth=2 expandtab tabstop=2 */