lemon-0.x: src/work/athos/lp/lp

     1 /* -*- C++ -*-

     2  * src/lemon/lp_base.h - Part of LEMON, a generic C++ optimization library

     3  *

     4  * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport

     5  * (Egervary Combinatorial Optimization Research Group, EGRES).

     6  *

     7  * Permission to use, modify and distribute this software is granted

     8  * provided that this copyright notice appears in all copies. For

     9  * precise terms see the accompanying LICENSE file.

    10  *

    11  * This software is provided "AS IS" with no warranty of any kind,

    12  * express or implied, and with no claim as to its suitability for any

    13  * purpose.

    14  *

    15  */

    17 #ifndef LEMON_LP_BASE_H

    18 #define LEMON_LP_BASE_H

    20 #include<vector>

    21 #include<map>

    22 #include<limits>

    23 #include<math.h>

    25 #include<lemon/utility.h>

    26 #include<lemon/error.h>

    27 #include<lemon/invalid.h>

    29 //#include"lin_expr.h"

    31 ///\file

    32 ///\brief The interface of the LP solver interface.

    33 namespace lemon {

    35   ///Internal data structure to convert floating id's to fix one's

    37   ///\todo This might by implemented to be usable in other places.

    38   class _FixId

    39   {

    40     std::vector<int> index;

    41     std::vector<int> cross;

    42     int first_free;

    43   public:

    44     _FixId() : first_free(-1) {};

    45     ///Convert a floating id to a fix one

    47     ///\param n is a floating id

    48     ///\return the corresponding fix id

    49     int fixId(int n) {return cross[n];}

    50     ///Convert a fix id to a floating one

    52     ///\param n is a fix id

    53     ///\return the corresponding floating id

    54     int floatingId(int n) { return index[n];}

    55     ///Add a new floating id.

    57     ///\param n is a floating id

    58     ///\return the fix id of the new value

    59     ///\todo Multiple additions should also be handled.

    60     int insert(int n)

    61     {

    62       if(n>=int(cross.size())) {

    63 	cross.resize(n+1);

    64 	if(first_free==-1) {

    65 	  cross[n]=index.size();

    66 	  index.push_back(n);

    67 	}

    68 	else {

    69 	  cross[n]=first_free;

    70 	  int next=index[first_free];

    71 	  index[first_free]=n;

    72 	  first_free=next;

    73 	}

    74 	return cross[n];

    75       }

    76       ///\todo Create an own exception type.

    77       else throw LogicError(); //floatingId-s must form a continuous range;

    78     }

    79     ///Remove a fix id.

    81     ///\param n is a fix id

    82     ///

    83     void erase(int n)

    84     {

    85       int fl=index[n];

    86       index[n]=first_free;

    87       first_free=n;

    88       for(int i=fl+1;i<int(cross.size());++i) {

    89 	cross[i-1]=cross[i];

    90 	index[cross[i]]--;

    91       }

    92       cross.pop_back();

    93     }

    94     ///An upper bound on the largest fix id.

    96     ///\todo Do we need this?

    97     ///

    98     std::size_t maxFixId() { return cross.size()-1; }

   100   };

   102   ///Common base class for LP solvers

   103   class LpSolverBase {

   105   public:

   107     ///\e

   108     enum SolutionType {

   109       ///\e

   110       INFEASIBLE = 0,

   111       ///\e

   112       UNBOUNDED = 1,

   113       ///\e

   114       OPTIMAL = 2,

   115       ///\e

   116       FEASIBLE = 3,

   117     };

   119     ///The floating point type used by the solver

   120     typedef double Value;

   121     ///The infinity constant

   122     static const Value INF;

   123     ///The not a number constant

   124     static const Value NaN;

   126     ///Refer to a column of the LP.

   128     ///This type is used to refer to a column of the LP.

   129     ///

   130     ///Its value remains valid and correct even after the addition or erase of

   131     ///other columns.

   132     ///

   133     ///\todo Document what can one do with a Col (INVALID, comparing,

   134     ///it is similar to Node/Edge)

   135     class Col {

   136     protected:

   137       int id;

   138       friend class LpSolverBase;

   139     public:

   140       typedef Value ExprValue;

   141       typedef True LpSolverCol;

   142       Col() {}

   143       Col(const Invalid&) : id(-1) {}

   144       bool operator<(Col c) const  {return id<c.id;}

   145       bool operator==(Col c) const  {return id==c.id;}

   146       bool operator!=(Col c) const  {return id==c.id;}

   147     };

   149     ///Refer to a row of the LP.

   151     ///This type is used to refer to a row of the LP.

   152     ///

   153     ///Its value remains valid and correct even after the addition or erase of

   154     ///other rows.

   155     ///

   156     ///\todo Document what can one do with a Row (INVALID, comparing,

   157     ///it is similar to Node/Edge)

   158     class Row {

   159     protected:

   160       int id;

   161       friend class LpSolverBase;

   162     public:

   163       typedef Value ExprValue;

   164       typedef True LpSolverRow;

   165       Row() {}

   166       Row(const Invalid&) : id(-1) {}

   167       typedef True LpSolverRow;

   168       bool operator<(Row c) const  {return id<c.id;}

   169       bool operator==(Row c) const  {return id==c.id;}

   170       bool operator!=(Row c) const  {return id==c.id;}

   171    };

   173     ///Linear expression

   174     //    typedef SparseLinExpr<Col> Expr;

   175     class Expr : public std::map<Col,Value>

   176     {

   177     public:

   178       typedef LpSolverBase::Col Key;

   179       typedef LpSolverBase::Value Value;

   181     protected:

   182       typedef std::map<Col,Value> Base;

   184       Value const_comp;

   185   public:

   186       typedef True IsLinExpression;

   187       ///\e

   188       Expr() : Base(), const_comp(0) { }

   189       ///\e

   190       Expr(const Key &v) : const_comp(0) {

   191 	Base::insert(std::make_pair(v, 1));

   192       }

   193       ///\e

   194       Expr(const Value &v) : const_comp(v) {}

   195       ///\e

   196       void set(const Key &v,const Value &c) {

   197 	Base::insert(std::make_pair(v, c));

   198       }

   199       ///\e

   200       Value &constComp() { return const_comp; }

   201       ///\e

   202       const Value &constComp() const { return const_comp; }

   204       ///Removes the components with zero coefficient.

   205       void simplify() {

   206 	for (Base::iterator i=Base::begin(); i!=Base::end();) {

   207 	  Base::iterator j=i;

   208 	  ++j;

   209 	  if ((*i).second==0) Base::erase(i);

   210 	  j=i;

   211 	}

   212       }

   214       ///Sets all coefficients and the constant component to 0.

   215       void clear() {

   216 	Base::clear();

   217 	const_comp=0;

   218       }

   220       ///\e

   221       Expr &operator+=(const Expr &e) {

   222 	for (Base::const_iterator j=e.begin(); j!=e.end(); ++j)

   223 	  (*this)[j->first]+=j->second;

   224 	///\todo it might be speeded up using "hints"

   225 	const_comp+=e.const_comp;

   226 	return *this;

   227       }

   228       ///\e

   229       Expr &operator-=(const Expr &e) {

   230 	for (Base::const_iterator j=e.begin(); j!=e.end(); ++j)

   231 	  (*this)[j->first]-=j->second;

   232 	const_comp-=e.const_comp;

   233 	return *this;

   234       }

   235       ///\e

   236       Expr &operator*=(const Value &c) {

   237 	for (Base::iterator j=Base::begin(); j!=Base::end(); ++j)

   238 	  j->second*=c;

   239 	const_comp*=c;

   240 	return *this;

   241       }

   242       ///\e

   243       Expr &operator/=(const Value &c) {

   244 	for (Base::iterator j=Base::begin(); j!=Base::end(); ++j)

   245 	  j->second/=c;

   246 	const_comp/=c;

   247 	return *this;

   248       }

   249     };

   251     ///Linear constraint

   252     //typedef LinConstr<Expr> Constr;

   253     class Constr

   254     {

   255     public:

   256       typedef LpSolverBase::Expr Expr;

   257       typedef Expr::Key Key;

   258       typedef Expr::Value Value;

   260       static const Value INF;

   261       static const Value NaN;

   262       //     static const Value INF=0;

   263       //     static const Value NaN=1;

   265     protected:

   266       Expr _expr;

   267       Value _lb,_ub;

   268     public:

   269       ///\e

   270       Constr() : _expr(), _lb(NaN), _ub(NaN) {}

   271       ///\e

   272       Constr(Value lb,const Expr &e,Value ub) :

   273 	_expr(e), _lb(lb), _ub(ub) {}

   274       ///\e

   275       Constr(const Expr &e,Value ub) :

   276 	_expr(e), _lb(NaN), _ub(ub) {}

   277       ///\e

   278       Constr(Value lb,const Expr &e) :

   279 	_expr(e), _lb(lb), _ub(NaN) {}

   280       ///\e

   281       Constr(const Expr &e) :

   282 	_expr(e), _lb(NaN), _ub(NaN) {}

   283       ///\e

   284       void clear()

   285       {

   286 	_expr.clear();

   287 	_lb=_ub=NaN;

   288       }

   289       ///\e

   290       Expr &expr() { return _expr; }

   291       ///\e

   292       const Expr &expr() const { return _expr; }

   293       ///\e

   294       Value &lowerBound() { return _lb; }

   295       ///\e

   296       const Value &lowerBound() const { return _lb; }

   297       ///\e

   298       Value &upperBound() { return _ub; }

   299       ///\e

   300       const Value &upperBound() const { return _ub; }

   301       ///\e

   302       bool lowerBounded() const { return std::isfinite(_lb); }

   303       ///\e

   304       bool upperBounded() const { return std::isfinite(_ub); }

   305     };

   308   protected:

   309     _FixId rows;

   310     _FixId cols;

   312     /// \e

   313     virtual int _addCol() = 0;

   314     /// \e

   315     virtual int _addRow() = 0;

   316     /// \e

   318     /// \warning Arrays are indexed from 1 (datum at index 0 is ignored)

   319     ///

   320     virtual void _setRowCoeffs(int i,

   321 			       int length,

   322                                int  const * indices,

   323                                Value  const * values ) = 0;

   324     /// \e

   326     /// \warning Arrays are indexed from 1 (datum at index 0 is ignored)

   327     ///

   328     virtual void _setColCoeffs(int i,

   329 			       int length,

   330                                int  const * indices,

   331                                Value  const * values ) = 0;

   333     /// \e

   335     /// The lower bound of a variable (column) have to be given by an

   336     /// extended number of type Value, i.e. a finite number of type

   337     /// Value or -\ref INF.

   338     virtual void _setColLowerBound(int i, Value value) = 0;

   339     /// \e

   341     /// The upper bound of a variable (column) have to be given by an

   342     /// extended number of type Value, i.e. a finite number of type

   343     /// Value or \ref INF.

   344     virtual void _setColUpperBound(int i, Value value) = 0;

   345     /// \e

   347     /// The lower bound of a linear expression (row) have to be given by an

   348     /// extended number of type Value, i.e. a finite number of type

   349     /// Value or -\ref INF.

   350     virtual void _setRowLowerBound(int i, Value value) = 0;

   351     /// \e

   353     /// The upper bound of a linear expression (row) have to be given by an

   354     /// extended number of type Value, i.e. a finite number of type

   355     /// Value or \ref INF.

   356     virtual void _setRowUpperBound(int i, Value value) = 0;

   358     /// \e

   359     virtual void _setObjCoeff(int i, Value obj_coef) = 0;

   361     ///\e

   363     ///\bug Wrong interface

   364     ///

   365     virtual SolutionType _solve() = 0;

   367     ///\e

   369     ///\bug Wrong interface

   370     ///

   371     virtual Value _getSolution(int i) = 0;

   372     ///\e

   374     ///\bug unimplemented!!!!

   375     void clearObj() {}

   376   public:

   379     ///\e

   380     virtual ~LpSolverBase() {}

   382     ///\name Building up and modification of the LP

   384     ///@{

   386     ///Add a new empty column (i.e a new variable) to the LP

   387     Col addCol() { Col c; c.id=cols.insert(_addCol()); return c;}

   389     ///\brief Fill the elements of a container with newly created columns

   390     ///(i.e a new variables)

   391     ///

   392     ///This magic function takes a container as its argument

   393     ///and fills its elements

   394     ///with new columns (i.e. variables)

   395     ///\param t can be

   396     ///- a standard STL compatible iterable container with

   397     ///\ref Col as its \c values_type

   398     ///like

   399     ///\code

   400     ///std::vector<LpSolverBase::Col>

   401     ///std::list<LpSolverBase::Col>

   402     ///\endcode

   403     ///- a standard STL compatible iterable container with

   404     ///\ref Col as its \c mapped_type

   405     ///like

   406     ///\code

   407     ///std::map<AnyType,LpSolverBase::Col>

   408     ///\endcode

   409     ///- an iterable lemon \ref concept::WriteMap "write map" like

   410     ///\code

   411     ///ListGraph::NodeMap<LpSolverBase::Col>

   412     ///ListGraph::EdgeMap<LpSolverBase::Col>

   413     ///\endcode

   414     ///\return The number of the created column.

   415     ///\bug Iterable nodemap hasn't been implemented yet.

   416 #ifdef DOXYGEN

   417     template<class T>

   418     int addColSet(T &t) { return 0;}

   419 #else

   420     template<class T>

   421     typename enable_if<typename T::value_type::LpSolverCol,int>::type

   422     addColSet(T &t,dummy<0> = 0) {

   423       int s=0;

   424       for(typename T::iterator i=t.begin();i!=t.end();++i) {*i=addCol();s++;}

   425       return s;

   426     }

   427     template<class T>

   428     typename enable_if<typename T::value_type::second_type::LpSolverCol,

   429 		       int>::type

   430     addColSet(T &t,dummy<1> = 1) {

   431       int s=0;

   432       for(typename T::iterator i=t.begin();i!=t.end();++i) {

   433 	i->second=addCol();

   434 	s++;

   435       }

   436       return s;

   437     }

   438     template<class T>

   439     typename enable_if<typename T::ValueSet::value_type::LpSolverCol,

   440 		       int>::type

   441     addColSet(T &t,dummy<2> = 2) {

   442       ///\bug <tt>return addColSet(t.valueSet());</tt> should also work.

   443       int s=0;

   444       for(typename T::ValueSet::iterator i=t.valueSet().begin();

   445 	  i!=t.valueSet().end();

   446 	  ++i)

   447 	{

   448 	  *i=addCol();

   449 	  s++;

   450 	}

   451       return s;

   452     }

   453 #endif

   455     ///Add a new empty row (i.e a new constaint) to the LP

   457     ///This function adds a new empty row (i.e a new constaint) to the LP.

   458     ///\return The created row

   459     Row addRow() { Row r; r.id=rows.insert(_addRow()); return r;}

   461     ///Set a row (i.e a constaint) of the LP

   463     ///\param r is the row to be modified

   464     ///\param l is lower bound (-\ref INF means no bound)

   465     ///\param e is a linear expression (see \ref Expr)

   466     ///\param u is the upper bound (\ref INF means no bound)

   467     ///\bug This is a temportary function. The interface will change to

   468     ///a better one.

   469     void setRow(Row r, Value l,const Expr &e, Value u) {

   470       std::vector<int> indices;

   471       std::vector<Value> values;

   472       indices.push_back(0);

   473       values.push_back(0);

   474       for(Expr::const_iterator i=e.begin(); i!=e.end(); ++i)

   475 	if((*i).second!=0) { ///\bug EPSILON would be necessary here!!!

   476 	  indices.push_back(cols.floatingId((*i).first.id));

   477 	  values.push_back((*i).second);

   478 	}

   479       _setRowCoeffs(rows.floatingId(r.id),indices.size()-1,

   480 		    &indices[0],&values[0]);

   481       _setRowLowerBound(rows.floatingId(r.id),l-e.constComp());

   482       _setRowUpperBound(rows.floatingId(r.id),u-e.constComp());

   483     }

   485     ///Set a row (i.e a constaint) of the LP

   487     ///\param r is the row to be modified

   488     ///\param c is a linear expression (see \ref Constr)

   489     void setRow(Row r, const Constr &c) {

   490       setRow(r,

   491 	     c.lowerBounded()?c.lowerBound():-INF,

   492 	     c.expr(),

   493 	     c.upperBounded()?c.upperBound():INF);

   494     }

   496     ///Add a new row (i.e a new constaint) to the LP

   498     ///\param l is the lower bound (-\ref INF means no bound)

   499     ///\param e is a linear expression (see \ref Expr)

   500     ///\param u is the upper bound (\ref INF means no bound)

   501     ///\return The created row.

   502     ///\bug This is a temportary function. The interface will change to

   503     ///a better one.

   504     Row addRow(Value l,const Expr &e, Value u) {

   505       Row r=addRow();

   506       setRow(r,l,e,u);

   507       return r;

   508     }

   510     ///Add a new row (i.e a new constaint) to the LP

   512     ///\param c is a linear expression (see \ref Constr)

   513     ///\return The created row.

   514     Row addRow(const Constr &c) {

   515       Row r=addRow();

   516       setRow(r,c);

   517       return r;

   518     }

   520     /// Set the lower bound of a column (i.e a variable)

   522     /// The upper bound of a variable (column) have to be given by an

   523     /// extended number of type Value, i.e. a finite number of type

   524     /// Value or -\ref INF.

   525     virtual void setColLowerBound(Col c, Value value) {

   526       _setColLowerBound(cols.floatingId(c.id),value);

   527     }

   528     /// Set the upper bound of a column (i.e a variable)

   530     /// The upper bound of a variable (column) have to be given by an

   531     /// extended number of type Value, i.e. a finite number of type

   532     /// Value or \ref INF.

   533     virtual void setColUpperBound(Col c, Value value) {

   534       _setColUpperBound(cols.floatingId(c.id),value);

   535     };

   536     /// Set the lower bound of a row (i.e a constraint)

   538     /// The lower bound of a linear expression (row) have to be given by an

   539     /// extended number of type Value, i.e. a finite number of type

   540     /// Value or -\ref INF.

   541     virtual void setRowLowerBound(Row r, Value value) {

   542       _setRowLowerBound(rows.floatingId(r.id),value);

   543     };

   544     /// Set the upper bound of a row (i.e a constraint)

   546     /// The upper bound of a linear expression (row) have to be given by an

   547     /// extended number of type Value, i.e. a finite number of type

   548     /// Value or \ref INF.

   549     virtual void setRowUpperBound(Row r, Value value) {

   550       _setRowUpperBound(rows.floatingId(r.id),value);

   551     };

   552     ///Set an element of the objective function

   553     void setObjCoeff(Col c, Value v) {_setObjCoeff(cols.floatingId(c.id),v); };

   554     ///Set the objective function

   556     ///\param e is a linear expression of type \ref Expr.

   557     ///\todo What to do with the constant component?

   558     void setObj(Expr e) {

   559       clearObj();

   560       for (Expr::iterator i=e.begin(); i!=e.end(); ++i)

   561 	setObjCoeff((*i).first,(*i).second);

   562     }

   564     ///@}

   567     ///\name Solving the LP

   569     ///@{

   571     ///\e

   572     SolutionType solve() { return _solve(); }

   574     ///@}

   576     ///\name Obtaining the solution LP

   578     ///@{

   580     ///\e

   581     Value solution(Col c) { return _getSolution(cols.floatingId(c.id)); }

   583     ///@}

   585   };

   587   ///\e

   589   ///\relates LpSolverBase::Expr

   590   ///

   591   inline LpSolverBase::Expr operator+(const LpSolverBase::Expr &a,

   592 				      const LpSolverBase::Expr &b)

   593   {

   594     LpSolverBase::Expr tmp(a);

   595     tmp+=b; ///\todo Don't STL have some special 'merge' algorithm?

   596     return tmp;

   597   }

   598   ///\e

   600   ///\relates LpSolverBase::Expr

   601   ///

   602   inline LpSolverBase::Expr operator-(const LpSolverBase::Expr &a,

   603 				      const LpSolverBase::Expr &b)

   604   {

   605     LpSolverBase::Expr tmp(a);

   606     tmp-=b; ///\todo Don't STL have some special 'merge' algorithm?

   607     return tmp;

   608   }

   609   ///\e

   611   ///\relates LpSolverBase::Expr

   612   ///

   613   inline LpSolverBase::Expr operator*(const LpSolverBase::Expr &a,

   614 				      const LpSolverBase::Value &b)

   615   {

   616     LpSolverBase::Expr tmp(a);

   617     tmp*=b; ///\todo Don't STL have some special 'merge' algorithm?

   618     return tmp;

   619   }

   621   ///\e

   623   ///\relates LpSolverBase::Expr

   624   ///

   625   inline LpSolverBase::Expr operator*(const LpSolverBase::Value &a,

   626 				      const LpSolverBase::Expr &b)

   627   {

   628     LpSolverBase::Expr tmp(b);

   629     tmp*=a; ///\todo Don't STL have some special 'merge' algorithm?

   630     return tmp;

   631   }

   632   ///\e

   634   ///\relates LpSolverBase::Expr

   635   ///

   636   inline LpSolverBase::Expr operator/(const LpSolverBase::Expr &a,

   637 				      const LpSolverBase::Value &b)

   638   {

   639     LpSolverBase::Expr tmp(a);

   640     tmp/=b; ///\todo Don't STL have some special 'merge' algorithm?

   641     return tmp;

   642   }

   644   ///\e

   646   ///\relates LpSolverBase::Constr

   647   ///

   648   inline LpSolverBase::Constr operator<=(const LpSolverBase::Expr &e,

   649 					 const LpSolverBase::Expr &f)

   650   {

   651     return LpSolverBase::Constr(-LpSolverBase::INF,e-f,0);

   652   }

   654   ///\e

   656   ///\relates LpSolverBase::Constr

   657   ///

   658   inline LpSolverBase::Constr operator<=(const LpSolverBase::Value &e,

   659 					 const LpSolverBase::Expr &f)

   660   {

   661     return LpSolverBase::Constr(e,f);

   662   }

   664   ///\e

   666   ///\relates LpSolverBase::Constr

   667   ///

   668   inline LpSolverBase::Constr operator<=(const LpSolverBase::Expr &e,

   669 					 const LpSolverBase::Value &f)

   670   {

   671     return LpSolverBase::Constr(e,f);

   672   }

   674   ///\e

   676   ///\relates LpSolverBase::Constr

   677   ///

   678   inline LpSolverBase::Constr operator>=(const LpSolverBase::Expr &e,

   679 					 const LpSolverBase::Expr &f)

   680   {

   681     return LpSolverBase::Constr(-LpSolverBase::INF,f-e,0);

   682   }

   685   ///\e

   687   ///\relates LpSolverBase::Constr

   688   ///

   689   inline LpSolverBase::Constr operator>=(const LpSolverBase::Value &e,

   690 					 const LpSolverBase::Expr &f)

   691   {

   692     return LpSolverBase::Constr(f,e);

   693   }

   696   ///\e

   698   ///\relates LpSolverBase::Constr

   699   ///

   700   inline LpSolverBase::Constr operator>=(const LpSolverBase::Expr &e,

   701 					 const LpSolverBase::Value &f)

   702   {

   703     return LpSolverBase::Constr(f,e);

   704   }

   706   ///\e

   708   ///\relates LpSolverBase::Constr

   709   ///

   710   inline LpSolverBase::Constr operator==(const LpSolverBase::Expr &e,

   711 					 const LpSolverBase::Expr &f)

   712   {

   713     return LpSolverBase::Constr(0,e-f,0);

   714   }

   716   ///\e

   718   ///\relates LpSolverBase::Constr

   719   ///

   720   inline LpSolverBase::Constr operator<=(const LpSolverBase::Value &n,

   721 					 const LpSolverBase::Constr&c)

   722   {

   723     LpSolverBase::Constr tmp(c);

   724     ///\todo Create an own exception type.

   725     if(!isnan(tmp.lowerBound())) throw LogicError();

   726     else tmp.lowerBound()=n;

   727     return tmp;

   728   }

   729   ///\e

   731   ///\relates LpSolverBase::Constr

   732   ///

   733   inline LpSolverBase::Constr operator<=(const LpSolverBase::Constr& c,

   734 					 const LpSolverBase::Value &n)

   735   {

   736     LpSolverBase::Constr tmp(c);

   737     ///\todo Create an own exception type.

   738     if(!isnan(tmp.upperBound())) throw LogicError();

   739     else tmp.upperBound()=n;

   740     return tmp;

   741   }

   743   ///\e

   745   ///\relates LpSolverBase::Constr

   746   ///

   747   inline LpSolverBase::Constr operator>=(const LpSolverBase::Value &n,

   748 					 const LpSolverBase::Constr&c)

   749   {

   750     LpSolverBase::Constr tmp(c);

   751     ///\todo Create an own exception type.

   752     if(!isnan(tmp.upperBound())) throw LogicError();

   753     else tmp.upperBound()=n;

   754     return tmp;

   755   }

   756   ///\e

   758   ///\relates LpSolverBase::Constr

   759   ///

   760   inline LpSolverBase::Constr operator>=(const LpSolverBase::Constr& c,

   761 					 const LpSolverBase::Value &n)

   762   {

   763     LpSolverBase::Constr tmp(c);

   764     ///\todo Create an own exception type.

   765     if(!isnan(tmp.lowerBound())) throw LogicError();

   766     else tmp.lowerBound()=n;

   767     return tmp;

   768   }

   771 } //namespace lemon

   773 #endif //LEMON_LP_BASE_H

author	alpar
	Wed, 30 Mar 2005 13:01:58 +0000
changeset 1275	16980bf77bd3
parent 1273	2b2ffa625775
child 1279	7caed393608e
permissions	-rw-r--r--