# HG changeset patch
# User ladanyi
# Date 1112692103 0
# Node ID c3dc75d4af24ce7c67f48da9bcc0b054559af2de
# Parent  c9c2e90b23427438bf0a7dd4d6fa6587e75b9de7
 - moved lp_base.h, lp_base.cc, lp_glpk.h, lp_glpk.cc, lp_solver_skeleton.h and
   lp_solver_skeleton.cc to src/lemon
 - modified the includes

diff -r c9c2e90b2342 -r c3dc75d4af24 src/lemon/Makefile.am
--- a/src/lemon/Makefile.am	Tue Apr 05 08:43:51 2005 +0000
+++ b/src/lemon/Makefile.am	Tue Apr 05 09:08:23 2005 +0000
@@ -4,7 +4,10 @@
 pkgconfig_DATA = lemon.pc
 
 lib_LTLIBRARIES = libemon.la
-libemon_la_SOURCES =
+libemon_la_SOURCES =							\
+	lp_base.cc							\
+	lp_glpk.cc							\
+	lp_solver_skeleton.cc
 
 pkginclude_HEADERS =							\
 	array_map.h                                                     \
diff -r c9c2e90b2342 -r c3dc75d4af24 src/lemon/lp_base.cc
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/lemon/lp_base.cc	Tue Apr 05 09:08:23 2005 +0000
@@ -0,0 +1,33 @@
+/* -*- C++ -*-
+ * src/lib/lp_base.cc - Part of LEMON, a generic C++ optimization library
+ *
+ * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
+ * (Egervary Combinatorial Optimization Research Group, EGRES).
+ *
+ * Permission to use, modify and distribute this software is granted
+ * provided that this copyright notice appears in all copies. For
+ * precise terms see the accompanying LICENSE file.
+ *
+ * This software is provided "AS IS" with no warranty of any kind,
+ * express or implied, and with no claim as to its suitability for any
+ * purpose.
+ *
+ */
+
+///\file
+///\brief The implementation of the LP solver interface.
+
+#include <lemon/lp_base.h>
+namespace lemon {
+  
+  const LpSolverBase::Value
+  LpSolverBase::INF = std::numeric_limits<Value>::infinity();
+  const LpSolverBase::Value
+  LpSolverBase::NaN = std::numeric_limits<Value>::quiet_NaN();
+
+  const LpSolverBase::Constr::Value
+  LpSolverBase::Constr::INF = std::numeric_limits<Value>::infinity();
+  const LpSolverBase::Constr::Value
+  LpSolverBase::Constr::NaN = std::numeric_limits<Value>::quiet_NaN();
+  
+} //namespace lemon
diff -r c9c2e90b2342 -r c3dc75d4af24 src/lemon/lp_base.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/lemon/lp_base.h	Tue Apr 05 09:08:23 2005 +0000
@@ -0,0 +1,823 @@
+/* -*- C++ -*-
+ * src/lemon/lp_base.h - Part of LEMON, a generic C++ optimization library
+ *
+ * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
+ * (Egervary Combinatorial Optimization Research Group, EGRES).
+ *
+ * Permission to use, modify and distribute this software is granted
+ * provided that this copyright notice appears in all copies. For
+ * precise terms see the accompanying LICENSE file.
+ *
+ * This software is provided "AS IS" with no warranty of any kind,
+ * express or implied, and with no claim as to its suitability for any
+ * purpose.
+ *
+ */
+
+#ifndef LEMON_LP_BASE_H
+#define LEMON_LP_BASE_H
+
+#include<vector>
+#include<map>
+#include<limits>
+#include<math.h>
+
+#include<lemon/utility.h>
+#include<lemon/error.h>
+#include<lemon/invalid.h>
+
+//#include"lin_expr.h"
+
+///\file
+///\brief The interface of the LP solver interface.
+namespace lemon {
+  
+  ///Internal data structure to convert floating id's to fix one's
+    
+  ///\todo This might be implemented to be also usable in other places.
+  class _FixId 
+  {
+    std::vector<int> index;
+    std::vector<int> cross;
+    int first_free;
+  public:
+    _FixId() : first_free(-1) {};
+    ///Convert a floating id to a fix one
+
+    ///\param n is a floating id
+    ///\return the corresponding fix id
+    int fixId(int n) {return cross[n];}
+    ///Convert a fix id to a floating one
+
+    ///\param n is a fix id
+    ///\return the corresponding floating id
+    int floatingId(int n) { return index[n];}
+    ///Add a new floating id.
+
+    ///\param n is a floating id
+    ///\return the fix id of the new value
+    ///\todo Multiple additions should also be handled.
+    int insert(int n)
+    {
+      if(n>=int(cross.size())) {
+	cross.resize(n+1);
+	if(first_free==-1) {
+	  cross[n]=index.size();
+	  index.push_back(n);
+	}
+	else {
+	  cross[n]=first_free;
+	  int next=index[first_free];
+	  index[first_free]=n;
+	  first_free=next;
+	}
+	return cross[n];
+      }
+      ///\todo Create an own exception type.
+      else throw LogicError(); //floatingId-s must form a continuous range;
+    }
+    ///Remove a fix id.
+
+    ///\param n is a fix id
+    ///
+    void erase(int n) 
+    {
+      int fl=index[n];
+      index[n]=first_free;
+      first_free=n;
+      for(int i=fl+1;i<int(cross.size());++i) {
+	cross[i-1]=cross[i];
+	index[cross[i]]--;
+      }
+      cross.pop_back();
+    }
+    ///An upper bound on the largest fix id.
+
+    ///\todo Do we need this?
+    ///
+    std::size_t maxFixId() { return cross.size()-1; }
+  
+  };
+    
+  ///Common base class for LP solvers
+  class LpSolverBase {
+    
+  public:
+
+    ///\e
+    enum SolveExitStatus {
+      ///\e
+      SOLVED = 0,
+      ///\e
+      UNSOLVED = 1
+    };
+      
+    ///\e
+    enum SolutionStatus {
+      ///Feasible solution has'n been found (but may exist).
+
+      ///\todo NOTFOUND might be a better name.
+      ///
+      UNDEFINED = 0,
+      ///The problem has no feasible solution
+      INFEASIBLE = 1,
+      ///Feasible solution found
+      FEASIBLE = 2,
+      ///Optimal solution exists and found
+      OPTIMAL = 3,
+      ///The cost function is unbounded
+
+      ///\todo Give a feasible solution and an infinite ray (and the
+      ///corresponding bases)
+      INFINITE = 4
+    };
+      
+    ///The floating point type used by the solver
+    typedef double Value;
+    ///The infinity constant
+    static const Value INF;
+    ///The not a number constant
+    static const Value NaN;
+    
+    ///Refer to a column of the LP.
+
+    ///This type is used to refer to a column of the LP.
+    ///
+    ///Its value remains valid and correct even after the addition or erase of
+    ///other columns.
+    ///
+    ///\todo Document what can one do with a Col (INVALID, comparing,
+    ///it is similar to Node/Edge)
+    class Col {
+    protected:
+      int id;
+      friend class LpSolverBase;
+    public:
+      typedef Value ExprValue;
+      typedef True LpSolverCol;
+      Col() {}
+      Col(const Invalid&) : id(-1) {}
+      bool operator<(Col c) const  {return id<c.id;}
+      bool operator==(Col c) const  {return id==c.id;}
+      bool operator!=(Col c) const  {return id==c.id;}
+    };
+
+    ///Refer to a row of the LP.
+
+    ///This type is used to refer to a row of the LP.
+    ///
+    ///Its value remains valid and correct even after the addition or erase of
+    ///other rows.
+    ///
+    ///\todo Document what can one do with a Row (INVALID, comparing,
+    ///it is similar to Node/Edge)
+    class Row {
+    protected:
+      int id;
+      friend class LpSolverBase;
+    public:
+      typedef Value ExprValue;
+      typedef True LpSolverRow;
+      Row() {}
+      Row(const Invalid&) : id(-1) {}
+      typedef True LpSolverRow;
+      bool operator<(Row c) const  {return id<c.id;}
+      bool operator==(Row c) const  {return id==c.id;}
+      bool operator!=(Row c) const  {return id==c.id;} 
+   };
+    
+    ///Linear expression of variables and a constant component
+    
+    ///This data structure strores a linear expression of the variables
+    ///(\ref Col "Col"s) and also has a constant component.
+    ///
+    ///There are several ways to access and modify the contents of this
+    ///container.
+    ///- Its it fully compatible with \c std::map<Col,double>, so for expamle
+    ///if \c e is an Expr and \c v and \c w are of type \ref Col then you can
+    ///read and modify the coefficients like
+    ///these.
+    ///\code
+    ///e[v]=5;
+    ///e[v]+=12;
+    ///e.erase(v);
+    ///\endcode
+    ///or you can also iterate through its elements.
+    ///\code
+    ///double s=0;
+    ///for(LpSolverBase::Expr::iterator i=e.begin();i!=e.end();++i)
+    ///  s+=i->second;
+    ///\endcode
+    ///(This code computes the sum of all coefficients).
+    ///- Numbers (<tt>double</tt>'s)
+    ///and variables (\ref Col "Col"s) directly convert to an
+    ///\ref Expr and the usual linear operations are defined so  
+    ///\code
+    ///v+w
+    ///2*v-3.12*(v-w/2)+2
+    ///v*2.1+(3*v+(v*12+w+6)*3)/2
+    ///\endcode
+    ///are valid expressions. The usual assignment operations are also defined.
+    ///\code
+    ///e=v+w;
+    ///e+=2*v-3.12*(v-w/2)+2;
+    ///e*=3.4;
+    ///e/=5;
+    ///\endcode
+    ///- The constant member can be set and read by \ref constComp()
+    ///\code
+    ///e.constComp()=12;
+    ///double c=e.constComp();
+    ///\endcode
+    ///
+    ///\note that \ref clear() not only sets all coefficients to 0 but also
+    ///clears the constant components.
+    class Expr : public std::map<Col,Value>
+    {
+    public:
+      typedef LpSolverBase::Col Key; 
+      typedef LpSolverBase::Value Value;
+      
+    protected:
+      typedef std::map<Col,Value> Base;
+      
+      Value const_comp;
+  public:
+      typedef True IsLinExpression;
+      ///\e
+      Expr() : Base(), const_comp(0) { }
+      ///\e
+      Expr(const Key &v) : const_comp(0) {
+	Base::insert(std::make_pair(v, 1));
+      }
+      ///\e
+      Expr(const Value &v) : const_comp(v) {}
+      ///\e
+      void set(const Key &v,const Value &c) {
+	Base::insert(std::make_pair(v, c));
+      }
+      ///\e
+      Value &constComp() { return const_comp; }
+      ///\e
+      const Value &constComp() const { return const_comp; }
+      
+      ///Removes the components with zero coefficient.
+      void simplify() {
+	for (Base::iterator i=Base::begin(); i!=Base::end();) {
+	  Base::iterator j=i;
+	  ++j;
+	  if ((*i).second==0) Base::erase(i);
+	  j=i;
+	}
+      }
+
+      ///Sets all coefficients and the constant component to 0.
+      void clear() {
+	Base::clear();
+	const_comp=0;
+      }
+
+      ///\e
+      Expr &operator+=(const Expr &e) {
+	for (Base::const_iterator j=e.begin(); j!=e.end(); ++j)
+	  (*this)[j->first]+=j->second;
+	///\todo it might be speeded up using "hints"
+	const_comp+=e.const_comp;
+	return *this;
+      }
+      ///\e
+      Expr &operator-=(const Expr &e) {
+	for (Base::const_iterator j=e.begin(); j!=e.end(); ++j)
+	  (*this)[j->first]-=j->second;
+	const_comp-=e.const_comp;
+	return *this;
+      }
+      ///\e
+      Expr &operator*=(const Value &c) {
+	for (Base::iterator j=Base::begin(); j!=Base::end(); ++j)
+	  j->second*=c;
+	const_comp*=c;
+	return *this;
+      }
+      ///\e
+      Expr &operator/=(const Value &c) {
+	for (Base::iterator j=Base::begin(); j!=Base::end(); ++j)
+	  j->second/=c;
+	const_comp/=c;
+	return *this;
+      }
+    };
+    
+    ///Linear constraint
+    //typedef LinConstr<Expr> Constr;
+    class Constr
+    {
+    public:
+      typedef LpSolverBase::Expr Expr;
+      typedef Expr::Key Key;
+      typedef Expr::Value Value;
+      
+      static const Value INF;
+      static const Value NaN;
+      //     static const Value INF=0;
+      //     static const Value NaN=1;
+      
+    protected:
+      Expr _expr;
+      Value _lb,_ub;
+    public:
+      ///\e
+      Constr() : _expr(), _lb(NaN), _ub(NaN) {}
+      ///\e
+      Constr(Value lb,const Expr &e,Value ub) :
+	_expr(e), _lb(lb), _ub(ub) {}
+      ///\e
+      Constr(const Expr &e,Value ub) : 
+	_expr(e), _lb(NaN), _ub(ub) {}
+      ///\e
+      Constr(Value lb,const Expr &e) :
+	_expr(e), _lb(lb), _ub(NaN) {}
+      ///\e
+      Constr(const Expr &e) : 
+	_expr(e), _lb(NaN), _ub(NaN) {}
+      ///\e
+      void clear() 
+      {
+	_expr.clear();
+	_lb=_ub=NaN;
+      }
+      ///\e
+      Expr &expr() { return _expr; }
+      ///\e
+      const Expr &expr() const { return _expr; }
+      ///\e
+      Value &lowerBound() { return _lb; }
+      ///\e
+      const Value &lowerBound() const { return _lb; }
+      ///\e
+      Value &upperBound() { return _ub; }
+      ///\e
+      const Value &upperBound() const { return _ub; }
+      ///\e
+      bool lowerBounded() const { 
+	using namespace std;
+	return isfinite(_lb);
+      }
+      ///\e
+      bool upperBounded() const {
+	using namespace std;
+	return isfinite(_ub);
+      }
+    };
+    
+
+  protected:
+    _FixId rows;
+    _FixId cols;
+
+    virtual int _addCol() = 0;
+    virtual int _addRow() = 0;
+    virtual void _setRowCoeffs(int i, 
+			       int length,
+                               int  const * indices, 
+                               Value  const * values ) = 0;
+    virtual void _setColCoeffs(int i, 
+			       int length,
+                               int  const * indices, 
+                               Value  const * values ) = 0;
+    virtual void _setColLowerBound(int i, Value value) = 0;
+    virtual void _setColUpperBound(int i, Value value) = 0;
+    virtual void _setRowLowerBound(int i, Value value) = 0;
+    virtual void _setRowUpperBound(int i, Value value) = 0;
+    virtual void _setObjCoeff(int i, Value obj_coef) = 0;
+    virtual SolveExitStatus _solve() = 0;
+    virtual Value _getPrimal(int i) = 0;
+    virtual SolutionStatus _getPrimalType() = 0;
+
+
+    void clearObj() {}
+  public:
+
+
+    ///\e
+    virtual ~LpSolverBase() {}
+
+    ///\name Build up and modify of the LP
+
+    ///@{
+
+    ///Add a new empty column (i.e a new variable) to the LP
+    Col addCol() { Col c; c.id=cols.insert(_addCol()); return c;}
+
+    ///\brief Adds several new columns
+    ///(i.e a variables) at once
+    ///
+    ///This magic function takes a container as its argument
+    ///and fills its elements
+    ///with new columns (i.e. variables)
+    ///\param t can be
+    ///- a standard STL compatible iterable container with
+    ///\ref Col as its \c values_type
+    ///like
+    ///\code
+    ///std::vector<LpSolverBase::Col>
+    ///std::list<LpSolverBase::Col>
+    ///\endcode
+    ///- a standard STL compatible iterable container with
+    ///\ref Col as its \c mapped_type
+    ///like
+    ///\code
+    ///std::map<AnyType,LpSolverBase::Col>
+    ///\endcode
+    ///- an iterable lemon \ref concept::WriteMap "write map" like 
+    ///\code
+    ///ListGraph::NodeMap<LpSolverBase::Col>
+    ///ListGraph::EdgeMap<LpSolverBase::Col>
+    ///\endcode
+    ///\return The number of the created column.
+    ///\bug Iterable nodemap hasn't been implemented yet.
+#ifdef DOXYGEN
+    template<class T>
+    int addColSet(T &t) { return 0;} 
+#else
+    template<class T>
+    typename enable_if<typename T::value_type::LpSolverCol,int>::type
+    addColSet(T &t,dummy<0> = 0) {
+      int s=0;
+      for(typename T::iterator i=t.begin();i!=t.end();++i) {*i=addCol();s++;}
+      return s;
+    }
+    template<class T>
+    typename enable_if<typename T::value_type::second_type::LpSolverCol,
+		       int>::type
+    addColSet(T &t,dummy<1> = 1) { 
+      int s=0;
+      for(typename T::iterator i=t.begin();i!=t.end();++i) {
+	i->second=addCol();
+	s++;
+      }
+      return s;
+    }
+    template<class T>
+    typename enable_if<typename T::ValueSet::value_type::LpSolverCol,
+		       int>::type
+    addColSet(T &t,dummy<2> = 2) { 
+      ///\bug <tt>return addColSet(t.valueSet());</tt> should also work.
+      int s=0;
+      for(typename T::ValueSet::iterator i=t.valueSet().begin();
+	  i!=t.valueSet().end();
+	  ++i)
+	{
+	  *i=addCol();
+	  s++;
+	}
+      return s;
+    }
+#endif
+
+    ///Add a new empty row (i.e a new constaint) to the LP
+
+    ///This function adds a new empty row (i.e a new constaint) to the LP.
+    ///\return The created row
+    Row addRow() { Row r; r.id=rows.insert(_addRow()); return r;}
+
+    ///Set a row (i.e a constaint) of the LP
+
+    ///\param r is the row to be modified
+    ///\param l is lower bound (-\ref INF means no bound)
+    ///\param e is a linear expression (see \ref Expr)
+    ///\param u is the upper bound (\ref INF means no bound)
+    ///\bug This is a temportary function. The interface will change to
+    ///a better one.
+    void setRow(Row r, Value l,const Expr &e, Value u) {
+      std::vector<int> indices;
+      std::vector<Value> values;
+      indices.push_back(0);
+      values.push_back(0);
+      for(Expr::const_iterator i=e.begin(); i!=e.end(); ++i)
+	if((*i).second!=0) { ///\bug EPSILON would be necessary here!!!
+	  indices.push_back(cols.floatingId((*i).first.id));
+	  values.push_back((*i).second);
+	}
+      _setRowCoeffs(rows.floatingId(r.id),indices.size()-1,
+		    &indices[0],&values[0]);
+      _setRowLowerBound(rows.floatingId(r.id),l-e.constComp());
+      _setRowUpperBound(rows.floatingId(r.id),u-e.constComp());
+    }
+
+    ///Set a row (i.e a constaint) of the LP
+
+    ///\param r is the row to be modified
+    ///\param c is a linear expression (see \ref Constr)
+    void setRow(Row r, const Constr &c) {
+      setRow(r,
+	     c.lowerBounded()?c.lowerBound():-INF,
+	     c.expr(),
+	     c.upperBounded()?c.upperBound():INF);
+    }
+
+    ///Add a new row (i.e a new constaint) to the LP
+
+    ///\param l is the lower bound (-\ref INF means no bound)
+    ///\param e is a linear expression (see \ref Expr)
+    ///\param u is the upper bound (\ref INF means no bound)
+    ///\return The created row.
+    ///\bug This is a temportary function. The interface will change to
+    ///a better one.
+    Row addRow(Value l,const Expr &e, Value u) {
+      Row r=addRow();
+      setRow(r,l,e,u);
+      return r;
+    }
+
+    ///Add a new row (i.e a new constaint) to the LP
+
+    ///\param c is a linear expression (see \ref Constr)
+    ///\return The created row.
+    Row addRow(const Constr &c) {
+      Row r=addRow();
+      setRow(r,c);
+      return r;
+    }
+
+    /// Set the lower bound of a column (i.e a variable)
+
+    /// The upper bound of a variable (column) has to be given by an 
+    /// extended number of type Value, i.e. a finite number of type 
+    /// Value or -\ref INF.
+    void colLowerBound(Col c, Value value) {
+      _setColLowerBound(cols.floatingId(c.id),value);
+    }
+    /// Set the upper bound of a column (i.e a variable)
+
+    /// The upper bound of a variable (column) has to be given by an 
+    /// extended number of type Value, i.e. a finite number of type 
+    /// Value or \ref INF.
+    void colUpperBound(Col c, Value value) {
+      _setColUpperBound(cols.floatingId(c.id),value);
+    };
+    /// Set the lower and the upper bounds of a column (i.e a variable)
+
+    /// The lower and the upper bounds of
+    /// a variable (column) have to be given by an 
+    /// extended number of type Value, i.e. a finite number of type 
+    /// Value, -\ref INF or \ref INF.
+    void colBounds(Col c, Value lower, Value upper) {
+      _setColLowerBound(cols.floatingId(c.id),lower);
+      _setColUpperBound(cols.floatingId(c.id),upper);
+    }
+    
+    /// Set the lower bound of a row (i.e a constraint)
+
+    /// The lower bound of a linear expression (row) has to be given by an 
+    /// extended number of type Value, i.e. a finite number of type 
+    /// Value or -\ref INF.
+    void rowLowerBound(Row r, Value value) {
+      _setRowLowerBound(rows.floatingId(r.id),value);
+    };
+    /// Set the upper bound of a row (i.e a constraint)
+
+    /// The upper bound of a linear expression (row) has to be given by an 
+    /// extended number of type Value, i.e. a finite number of type 
+    /// Value or \ref INF.
+    void rowUpperBound(Row r, Value value) {
+      _setRowUpperBound(rows.floatingId(r.id),value);
+    };
+    /// Set the lower and the upper bounds of a row (i.e a variable)
+
+    /// The lower and the upper bounds of
+    /// a constraint (row) have to be given by an 
+    /// extended number of type Value, i.e. a finite number of type 
+    /// Value, -\ref INF or \ref INF.
+    void rowBounds(Row c, Value lower, Value upper) {
+      _setRowLowerBound(rows.floatingId(c.id),lower);
+      _setRowUpperBound(rows.floatingId(c.id),upper);
+    }
+    
+    ///Set an element of the objective function
+    void objCoeff(Col c, Value v) {_setObjCoeff(cols.floatingId(c.id),v); };
+    ///Set the objective function
+    
+    ///\param e is a linear expression of type \ref Expr.
+    ///\todo What to do with the constant component?
+    void setObj(Expr e) {
+      clearObj();
+      for (Expr::iterator i=e.begin(); i!=e.end(); ++i)
+	objCoeff((*i).first,(*i).second);
+    }
+
+    ///@}
+
+
+    ///\name Solve the LP
+
+    ///@{
+
+    ///\e
+    SolveExitStatus solve() { return _solve(); }
+    
+    ///@}
+    
+    ///\name Obtain the solution
+
+    ///@{
+
+    ///\e
+    SolutionStatus primalType() {
+      return _getPrimalType();
+    }
+
+    ///\e
+    Value primal(Col c) { return _getPrimal(cols.floatingId(c.id)); }
+
+    ///@}
+    
+  };  
+
+  ///\e
+  
+  ///\relates LpSolverBase::Expr
+  ///
+  inline LpSolverBase::Expr operator+(const LpSolverBase::Expr &a,
+				      const LpSolverBase::Expr &b) 
+  {
+    LpSolverBase::Expr tmp(a);
+    tmp+=b; ///\todo Don't STL have some special 'merge' algorithm?
+    return tmp;
+  }
+  ///\e
+  
+  ///\relates LpSolverBase::Expr
+  ///
+  inline LpSolverBase::Expr operator-(const LpSolverBase::Expr &a,
+				      const LpSolverBase::Expr &b) 
+  {
+    LpSolverBase::Expr tmp(a);
+    tmp-=b; ///\todo Don't STL have some special 'merge' algorithm?
+    return tmp;
+  }
+  ///\e
+  
+  ///\relates LpSolverBase::Expr
+  ///
+  inline LpSolverBase::Expr operator*(const LpSolverBase::Expr &a,
+				      const LpSolverBase::Value &b) 
+  {
+    LpSolverBase::Expr tmp(a);
+    tmp*=b; ///\todo Don't STL have some special 'merge' algorithm?
+    return tmp;
+  }
+  
+  ///\e
+  
+  ///\relates LpSolverBase::Expr
+  ///
+  inline LpSolverBase::Expr operator*(const LpSolverBase::Value &a,
+				      const LpSolverBase::Expr &b) 
+  {
+    LpSolverBase::Expr tmp(b);
+    tmp*=a; ///\todo Don't STL have some special 'merge' algorithm?
+    return tmp;
+  }
+  ///\e
+  
+  ///\relates LpSolverBase::Expr
+  ///
+  inline LpSolverBase::Expr operator/(const LpSolverBase::Expr &a,
+				      const LpSolverBase::Value &b) 
+  {
+    LpSolverBase::Expr tmp(a);
+    tmp/=b; ///\todo Don't STL have some special 'merge' algorithm?
+    return tmp;
+  }
+  
+  ///\e
+  
+  ///\relates LpSolverBase::Constr
+  ///
+  inline LpSolverBase::Constr operator<=(const LpSolverBase::Expr &e,
+					 const LpSolverBase::Expr &f) 
+  {
+    return LpSolverBase::Constr(-LpSolverBase::INF,e-f,0);
+  }
+
+  ///\e
+  
+  ///\relates LpSolverBase::Constr
+  ///
+  inline LpSolverBase::Constr operator<=(const LpSolverBase::Value &e,
+					 const LpSolverBase::Expr &f) 
+  {
+    return LpSolverBase::Constr(e,f);
+  }
+
+  ///\e
+  
+  ///\relates LpSolverBase::Constr
+  ///
+  inline LpSolverBase::Constr operator<=(const LpSolverBase::Expr &e,
+					 const LpSolverBase::Value &f) 
+  {
+    return LpSolverBase::Constr(e,f);
+  }
+
+  ///\e
+  
+  ///\relates LpSolverBase::Constr
+  ///
+  inline LpSolverBase::Constr operator>=(const LpSolverBase::Expr &e,
+					 const LpSolverBase::Expr &f) 
+  {
+    return LpSolverBase::Constr(-LpSolverBase::INF,f-e,0);
+  }
+
+
+  ///\e
+  
+  ///\relates LpSolverBase::Constr
+  ///
+  inline LpSolverBase::Constr operator>=(const LpSolverBase::Value &e,
+					 const LpSolverBase::Expr &f) 
+  {
+    return LpSolverBase::Constr(f,e);
+  }
+
+
+  ///\e
+  
+  ///\relates LpSolverBase::Constr
+  ///
+  inline LpSolverBase::Constr operator>=(const LpSolverBase::Expr &e,
+					 const LpSolverBase::Value &f) 
+  {
+    return LpSolverBase::Constr(f,e);
+  }
+
+  ///\e
+  
+  ///\relates LpSolverBase::Constr
+  ///
+  inline LpSolverBase::Constr operator==(const LpSolverBase::Expr &e,
+					 const LpSolverBase::Expr &f) 
+  {
+    return LpSolverBase::Constr(0,e-f,0);
+  }
+
+  ///\e
+  
+  ///\relates LpSolverBase::Constr
+  ///
+  inline LpSolverBase::Constr operator<=(const LpSolverBase::Value &n,
+					 const LpSolverBase::Constr&c) 
+  {
+    LpSolverBase::Constr tmp(c);
+    ///\todo Create an own exception type.
+    if(!isnan(tmp.lowerBound())) throw LogicError();
+    else tmp.lowerBound()=n;
+    return tmp;
+  }
+  ///\e
+  
+  ///\relates LpSolverBase::Constr
+  ///
+  inline LpSolverBase::Constr operator<=(const LpSolverBase::Constr& c,
+					 const LpSolverBase::Value &n)
+  {
+    LpSolverBase::Constr tmp(c);
+    ///\todo Create an own exception type.
+    if(!isnan(tmp.upperBound())) throw LogicError();
+    else tmp.upperBound()=n;
+    return tmp;
+  }
+
+  ///\e
+  
+  ///\relates LpSolverBase::Constr
+  ///
+  inline LpSolverBase::Constr operator>=(const LpSolverBase::Value &n,
+					 const LpSolverBase::Constr&c) 
+  {
+    LpSolverBase::Constr tmp(c);
+    ///\todo Create an own exception type.
+    if(!isnan(tmp.upperBound())) throw LogicError();
+    else tmp.upperBound()=n;
+    return tmp;
+  }
+  ///\e
+  
+  ///\relates LpSolverBase::Constr
+  ///
+  inline LpSolverBase::Constr operator>=(const LpSolverBase::Constr& c,
+					 const LpSolverBase::Value &n)
+  {
+    LpSolverBase::Constr tmp(c);
+    ///\todo Create an own exception type.
+    if(!isnan(tmp.lowerBound())) throw LogicError();
+    else tmp.lowerBound()=n;
+    return tmp;
+  }
+
+
+} //namespace lemon
+
+#endif //LEMON_LP_BASE_H
diff -r c9c2e90b2342 -r c3dc75d4af24 src/lemon/lp_glpk.cc
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/lemon/lp_glpk.cc	Tue Apr 05 09:08:23 2005 +0000
@@ -0,0 +1,288 @@
+/* -*- C++ -*-
+ * src/lemon/lp_glpk.cc - Part of LEMON, a generic C++ optimization library
+ *
+ * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
+ * (Egervary Combinatorial Optimization Research Group, EGRES).
+ *
+ * Permission to use, modify and distribute this software is granted
+ * provided that this copyright notice appears in all copies. For
+ * precise terms see the accompanying LICENSE file.
+ *
+ * This software is provided "AS IS" with no warranty of any kind,
+ * express or implied, and with no claim as to its suitability for any
+ * purpose.
+ *
+ */
+
+#ifndef LEMON_LP_GLPK_CC
+#define LEMON_LP_GLPK_CC
+
+///\file
+///\brief Implementation of the LEMON-GLPK lp solver interface.
+
+#include <lemon/lp_glpk.h>
+
+namespace lemon {
+
+    /// \e
+    int LpGlpk::_addCol() { 
+	int i=lpx_add_cols(lp, 1);
+	_setColLowerBound(i, -INF);
+	_setColUpperBound(i, INF);
+	return i;
+    }
+
+    /// \e
+    int LpGlpk::_addRow() { 
+	int i=lpx_add_rows(lp, 1);
+	return i;
+    }
+
+  
+    void LpGlpk::_setRowCoeffs(int i, 
+			       int length,
+			       const int   * indices, 
+			       const Value   * values )
+    {
+      lpx_set_mat_row(lp, i, length,
+		      const_cast<int * >(indices) ,
+		      const_cast<Value * >(values));
+    }
+  
+    void LpGlpk::_setColCoeffs(int i, 
+			       int length,
+			       const int   * indices, 
+			       const Value   * values)
+    {
+      lpx_set_mat_col(lp, i, length,
+		      const_cast<int * >(indices),
+		      const_cast<Value * >(values));
+    }
+  
+    void LpGlpk::_setColLowerBound(int i, Value lo)
+    {
+      if (lo==INF) {
+	//FIXME error
+      }
+      int b=lpx_get_col_type(lp, i);
+      double up=lpx_get_col_ub(lp, i);	
+      if (lo==-INF) {
+	switch (b) {
+	case LPX_FR:
+	case LPX_LO:
+	  lpx_set_col_bnds(lp, i, LPX_FR, lo, up);
+	  break;
+	case LPX_UP:
+	  break;
+	case LPX_DB:
+	case LPX_FX:
+	  lpx_set_col_bnds(lp, i, LPX_UP, lo, up);
+	  break;
+	default: ;
+	  //FIXME error
+	}
+      } else {
+	switch (b) {
+	case LPX_FR:
+	case LPX_LO:
+	  lpx_set_col_bnds(lp, i, LPX_LO, lo, up);
+	  break;
+	case LPX_UP:	  
+	case LPX_DB:
+	case LPX_FX:
+	  if (lo==up) 
+	    lpx_set_col_bnds(lp, i, LPX_FX, lo, up);
+	  else 
+	    lpx_set_col_bnds(lp, i, LPX_DB, lo, up);
+	  break;
+	default: ;
+	  //FIXME error
+	}
+      }
+
+    }
+  
+    void LpGlpk::_setColUpperBound(int i, Value up)
+    {
+      if (up==-INF) {
+	//FIXME error
+      }
+      int b=lpx_get_col_type(lp, i);
+      double lo=lpx_get_col_lb(lp, i);
+      if (up==INF) {
+	switch (b) {
+	case LPX_FR:
+	case LPX_LO:
+	  break;
+	case LPX_UP:
+	  lpx_set_col_bnds(lp, i, LPX_FR, lo, up);
+	  break;
+	case LPX_DB:
+	case LPX_FX:
+	  lpx_set_col_bnds(lp, i, LPX_LO, lo, up);
+	  break;
+	default: ;
+	  //FIXME error
+	}
+      } else {
+	switch (b) {
+	case LPX_FR:
+	  lpx_set_col_bnds(lp, i, LPX_UP, lo, up);
+	  break;
+	case LPX_UP:
+	  lpx_set_col_bnds(lp, i, LPX_UP, lo, up);
+	  break;
+	case LPX_LO:
+	case LPX_DB:
+	case LPX_FX:
+	  if (lo==up) 
+	    lpx_set_col_bnds(lp, i, LPX_FX, lo, up);
+	  else 
+	    lpx_set_col_bnds(lp, i, LPX_DB, lo, up);
+	  break;
+	default: ;
+	  //FIXME error
+	}
+      }
+    }
+  
+    void LpGlpk::_setRowLowerBound(int i, Value lo)
+    {
+      if (lo==INF) {
+	//FIXME error
+      }
+      int b=lpx_get_row_type(lp, i);
+      double up=lpx_get_row_ub(lp, i);	
+      if (lo==-INF) {
+	switch (b) {
+	case LPX_FR:
+	case LPX_LO:
+	  lpx_set_row_bnds(lp, i, LPX_FR, lo, up);
+	  break;
+	case LPX_UP:
+	  break;
+	case LPX_DB:
+	case LPX_FX:
+	  lpx_set_row_bnds(lp, i, LPX_UP, lo, up);
+	  break;
+	default: ;
+	  //FIXME error
+	}
+      } else {
+	switch (b) {
+	case LPX_FR:
+	case LPX_LO:
+	  lpx_set_row_bnds(lp, i, LPX_LO, lo, up);
+	  break;
+	case LPX_UP:	  
+	case LPX_DB:
+	case LPX_FX:
+	  if (lo==up) 
+	    lpx_set_row_bnds(lp, i, LPX_FX, lo, up);
+	  else 
+	    lpx_set_row_bnds(lp, i, LPX_DB, lo, up);
+	  break;
+	default: ;
+	  //FIXME error
+	}
+      }
+    }
+  
+  void LpGlpk::_setRowUpperBound(int i, Value up)
+  {
+    if (up==-INF) {
+      //FIXME error
+    }
+    int b=lpx_get_row_type(lp, i);
+    double lo=lpx_get_row_lb(lp, i);
+    if (up==INF) {
+      switch (b) {
+      case LPX_FR:
+      case LPX_LO:
+	break;
+      case LPX_UP:
+	lpx_set_row_bnds(lp, i, LPX_FR, lo, up);
+	break;
+      case LPX_DB:
+      case LPX_FX:
+	lpx_set_row_bnds(lp, i, LPX_LO, lo, up);
+	break;
+      default: ;
+	//FIXME error
+      }
+    } else {
+      switch (b) {
+      case LPX_FR:
+	lpx_set_row_bnds(lp, i, LPX_UP, lo, up);
+	break;
+      case LPX_UP:
+	lpx_set_row_bnds(lp, i, LPX_UP, lo, up);
+	break;
+      case LPX_LO:
+      case LPX_DB:
+      case LPX_FX:
+	if (lo==up) 
+	  lpx_set_row_bnds(lp, i, LPX_FX, lo, up);
+	else 
+	  lpx_set_row_bnds(lp, i, LPX_DB, lo, up);
+	break;
+      default: ;
+	//FIXME error
+      }
+    }
+  }
+  
+  void LpGlpk::_setObjCoeff(int i, Value obj_coef)
+  {
+    lpx_set_obj_coef(lp, i, obj_coef);
+  }
+
+
+  LpGlpk::SolveExitStatus LpGlpk::_solve()
+  {
+    int i=  lpx_simplex(lp);
+    switch (i) {
+    case LPX_E_OK: 
+      return SOLVED;
+      break;
+    default:
+      return UNSOLVED;
+    }
+  }
+
+  LpGlpk::Value LpGlpk::_getPrimal(int i)
+  {
+    return lpx_get_col_prim(lp,i);
+  }
+  
+ 
+  LpGlpk::SolutionStatus LpGlpk::_getPrimalType()
+  {
+    int stat=  lpx_get_status(lp);
+    switch (stat) {
+    case LPX_UNDEF://Undefined (no solve has been run yet)
+      return UNDEFINED;
+      break;
+    case LPX_NOFEAS://There is no feasible solution (primal, I guess)
+    case LPX_INFEAS://Infeasible 
+      return INFEASIBLE;
+      break;
+    case LPX_UNBND://Unbounded
+      return INFINITE;
+      break;
+    case LPX_FEAS://Feasible
+      return FEASIBLE;
+      break;
+    case LPX_OPT://Feasible
+      return OPTIMAL;
+      break;
+    default:
+      return UNDEFINED; //to avoid gcc warning
+      //FIXME error
+    }
+  }
+
+
+} //END OF NAMESPACE LEMON
+
+#endif //LEMON_LP_GLPK_CC
diff -r c9c2e90b2342 -r c3dc75d4af24 src/lemon/lp_glpk.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/lemon/lp_glpk.h	Tue Apr 05 09:08:23 2005 +0000
@@ -0,0 +1,89 @@
+/* -*- C++ -*-
+ * src/lemon/lp_glpk.h - Part of LEMON, a generic C++ optimization library
+ *
+ * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
+ * (Egervary Combinatorial Optimization Research Group, EGRES).
+ *
+ * Permission to use, modify and distribute this software is granted
+ * provided that this copyright notice appears in all copies. For
+ * precise terms see the accompanying LICENSE file.
+ *
+ * This software is provided "AS IS" with no warranty of any kind,
+ * express or implied, and with no claim as to its suitability for any
+ * purpose.
+ *
+ */
+
+#ifndef LEMON_LP_GLPK_H
+#define LEMON_LP_GLPK_H
+
+///\file
+///\brief Header of the LEMON-GLPK lp solver interface.
+
+#include "lp_base.h"
+extern "C" {
+#include "glpk.h"
+}
+
+namespace lemon {
+
+
+  /// \brief Wrapper for GLPK solver
+  /// 
+  /// This class implements a lemon wrapper for GLPK.
+  class LpGlpk : public LpSolverBase {
+
+  public:
+
+    typedef LpSolverBase Parent;
+    
+    /// \e
+    LPX* lp;
+
+    /// \e
+    LpGlpk() : Parent(), 
+			lp(lpx_create_prob()) {
+      lpx_set_int_parm(lp, LPX_K_DUAL, 1);
+    }
+    /// \e
+    ~LpGlpk() {
+      lpx_delete_prob(lp);
+    }
+
+  protected:
+    virtual int _addCol();
+    virtual int _addRow();
+    virtual void _setRowCoeffs(int i, 
+			       int length,
+                               const int   * indices, 
+                               const Value   * values );
+    virtual void _setColCoeffs(int i, 
+			       int length,
+                               const int   * indices, 
+                               const Value   * values);
+    virtual void _setColLowerBound(int i, Value value);
+    virtual void _setColUpperBound(int i, Value value);
+    virtual void _setRowLowerBound(int i, Value value);
+    virtual void _setRowUpperBound(int i, Value value);
+    virtual void _setObjCoeff(int i, Value obj_coef);
+    ///\e
+    
+    ///\bug Unimplemented
+    ///
+    virtual SolveExitStatus _solve();
+    ///\e
+    
+    ///\bug Unimplemented
+    ///
+    virtual Value _getPrimal(int i);
+    ///\e
+    
+    ///\bug Unimplemented
+    ///
+    virtual SolutionStatus _getPrimalType();
+
+  };
+} //END OF NAMESPACE LEMON
+
+#endif //LEMON_LP_GLPK_H
+
diff -r c9c2e90b2342 -r c3dc75d4af24 src/lemon/lp_solver_skeleton.cc
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/lemon/lp_solver_skeleton.cc	Tue Apr 05 09:08:23 2005 +0000
@@ -0,0 +1,84 @@
+/* -*- C++ -*-
+ * src/lemon/lp_solver_skeleton.cc
+ * - Part of LEMON, a generic C++ optimization library
+ *
+ * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
+ * (Egervary Combinatorial Optimization Research Group, EGRES).
+ *
+ * Permission to use, modify and distribute this software is granted
+ * provided that this copyright notice appears in all copies. For
+ * precise terms see the accompanying LICENSE file.
+ *
+ * This software is provided "AS IS" with no warranty of any kind,
+ * express or implied, and with no claim as to its suitability for any
+ * purpose.
+ *
+ */
+
+#include <lemon/lp_solver_skeleton.h>
+
+///\file
+///\brief A skeleton file to implement LP solver interfaces
+namespace lemon {
+  
+  int LpSolverSkeleton::_addCol()
+  {
+    return ++col_num;
+  }
+  
+  int LpSolverSkeleton::_addRow() 
+  {
+    return ++row_num;
+  }
+  
+  void LpSolverSkeleton::_setRowCoeffs(int i, 
+					       int length,
+					       int  const * indices, 
+					       Value  const * values )
+  {
+  }
+  
+  void LpSolverSkeleton::_setColCoeffs(int i, 
+					       int length,
+					       int  const * indices, 
+					       Value  const * values)
+  {
+  }
+  
+  void LpSolverSkeleton::_setColLowerBound(int i, Value value)
+  {
+  }
+  
+  void LpSolverSkeleton::_setColUpperBound(int i, Value value)
+  {
+  }
+  
+  void LpSolverSkeleton::_setRowLowerBound(int i, Value value)
+  {
+  }
+  
+  void LpSolverSkeleton::_setRowUpperBound(int i, Value value)
+  {
+  }
+  
+  void LpSolverSkeleton::_setObjCoeff(int i, Value obj_coef)
+  {
+  }
+
+  LpSolverSkeleton::SolveExitStatus LpSolverSkeleton::_solve()
+  {
+    return SOLVED;
+  }
+
+  LpSolverSkeleton::Value LpSolverSkeleton::_getPrimal(int i)
+  {
+    return 0;
+  }
+  
+  LpSolverSkeleton::SolutionStatus LpSolverSkeleton::_getPrimalType()
+  {
+    return OPTIMAL;
+  }
+  
+} //namespace lemon
+
diff -r c9c2e90b2342 -r c3dc75d4af24 src/lemon/lp_solver_skeleton.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/lemon/lp_solver_skeleton.h	Tue Apr 05 09:08:23 2005 +0000
@@ -0,0 +1,104 @@
+/* -*- C++ -*-
+ * src/lemon/lp_solver_skeleton.h
+ * - Part of LEMON, a generic C++ optimization library
+ *
+ * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
+ * (Egervary Combinatorial Optimization Research Group, EGRES).
+ *
+ * Permission to use, modify and distribute this software is granted
+ * provided that this copyright notice appears in all copies. For
+ * precise terms see the accompanying LICENSE file.
+ *
+ * This software is provided "AS IS" with no warranty of any kind,
+ * express or implied, and with no claim as to its suitability for any
+ * purpose.
+ *
+ */
+
+#ifndef LEMON_LP_SOLVER_SKELETON
+#define LEMON_LP_SOLVER_SKELETON
+
+#include"lp_base.h"
+
+///\file
+///\brief A skeleton file to implement LP solver interfaces
+namespace lemon {
+  
+  ///A skeleton class to implement LP solver interfaces
+  class LpSolverSkeleton :public LpSolverBase {
+    int col_num,row_num;
+    
+  protected:
+    /// \e
+    virtual int _addCol();
+    /// \e
+    virtual int _addRow();
+    /// \e
+
+    /// \warning Arrays are indexed from 1 (datum at index 0 is ignored)
+    ///
+    virtual void _setRowCoeffs(int i, 
+			       int length,
+                               int  const * indices, 
+                               Value  const * values );
+    /// \e
+
+    /// \warning Arrays are indexed from 1 (datum at index 0 is ignored)
+    ///
+    virtual void _setColCoeffs(int i, 
+			       int length,
+                               int  const * indices, 
+                               Value  const * values );
+    
+    /// \e
+
+    /// The lower bound of a variable (column) have to be given by an 
+    /// extended number of type Value, i.e. a finite number of type 
+    /// Value or -\ref INF.
+    virtual void _setColLowerBound(int i, Value value);
+    /// \e
+
+    /// The upper bound of a variable (column) have to be given by an 
+    /// extended number of type Value, i.e. a finite number of type 
+    /// Value or \ref INF.
+    virtual void _setColUpperBound(int i, Value value);
+    /// \e
+
+    /// The lower bound of a linear expression (row) have to be given by an 
+    /// extended number of type Value, i.e. a finite number of type 
+    /// Value or -\ref INF.
+    virtual void _setRowLowerBound(int i, Value value);
+    /// \e
+
+    /// The upper bound of a linear expression (row) have to be given by an 
+    /// extended number of type Value, i.e. a finite number of type 
+    /// Value or \ref INF.
+    virtual void _setRowUpperBound(int i, Value value);
+
+    /// \e
+    virtual void _setObjCoeff(int i, Value obj_coef);
+
+    ///\e
+    
+    ///\bug Wrong interface
+    ///
+    virtual SolveExitStatus _solve();
+
+    ///\e
+
+    ///\bug Wrong interface
+    ///
+    virtual Value _getPrimal(int i);
+    ///\e
+
+    ///\bug Wrong interface
+    ///
+    virtual SolutionStatus _getPrimalType();
+
+  public:
+    LpSolverSkeleton() : LpSolverBase(), col_num(0), row_num(0) {}
+  };  
+
+} //namespace lemon
+
+#endif // LEMON_LP_SOLVER_SKELETON
diff -r c9c2e90b2342 -r c3dc75d4af24 src/work/athos/lp/lp_base.cc
--- a/src/work/athos/lp/lp_base.cc	Tue Apr 05 08:43:51 2005 +0000
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,33 +0,0 @@
-/* -*- C++ -*-
- * src/lib/lp_base.cc - Part of LEMON, a generic C++ optimization library
- *
- * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
- * (Egervary Combinatorial Optimization Research Group, EGRES).
- *
- * Permission to use, modify and distribute this software is granted
- * provided that this copyright notice appears in all copies. For
- * precise terms see the accompanying LICENSE file.
- *
- * This software is provided "AS IS" with no warranty of any kind,
- * express or implied, and with no claim as to its suitability for any
- * purpose.
- *
- */
-
-///\file
-///\brief The implementation of the LP solver interface.
-
-#include "lp_base.h"
-namespace lemon {
-  
-  const LpSolverBase::Value
-  LpSolverBase::INF = std::numeric_limits<Value>::infinity();
-  const LpSolverBase::Value
-  LpSolverBase::NaN = std::numeric_limits<Value>::quiet_NaN();
-
-  const LpSolverBase::Constr::Value
-  LpSolverBase::Constr::INF = std::numeric_limits<Value>::infinity();
-  const LpSolverBase::Constr::Value
-  LpSolverBase::Constr::NaN = std::numeric_limits<Value>::quiet_NaN();
-  
-} //namespace lemon
diff -r c9c2e90b2342 -r c3dc75d4af24 src/work/athos/lp/lp_base.h
--- a/src/work/athos/lp/lp_base.h	Tue Apr 05 08:43:51 2005 +0000
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,823 +0,0 @@
-/* -*- C++ -*-
- * src/lemon/lp_base.h - Part of LEMON, a generic C++ optimization library
- *
- * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
- * (Egervary Combinatorial Optimization Research Group, EGRES).
- *
- * Permission to use, modify and distribute this software is granted
- * provided that this copyright notice appears in all copies. For
- * precise terms see the accompanying LICENSE file.
- *
- * This software is provided "AS IS" with no warranty of any kind,
- * express or implied, and with no claim as to its suitability for any
- * purpose.
- *
- */
-
-#ifndef LEMON_LP_BASE_H
-#define LEMON_LP_BASE_H
-
-#include<vector>
-#include<map>
-#include<limits>
-#include<math.h>
-
-#include<lemon/utility.h>
-#include<lemon/error.h>
-#include<lemon/invalid.h>
-
-//#include"lin_expr.h"
-
-///\file
-///\brief The interface of the LP solver interface.
-namespace lemon {
-  
-  ///Internal data structure to convert floating id's to fix one's
-    
-  ///\todo This might be implemented to be also usable in other places.
-  class _FixId 
-  {
-    std::vector<int> index;
-    std::vector<int> cross;
-    int first_free;
-  public:
-    _FixId() : first_free(-1) {};
-    ///Convert a floating id to a fix one
-
-    ///\param n is a floating id
-    ///\return the corresponding fix id
-    int fixId(int n) {return cross[n];}
-    ///Convert a fix id to a floating one
-
-    ///\param n is a fix id
-    ///\return the corresponding floating id
-    int floatingId(int n) { return index[n];}
-    ///Add a new floating id.
-
-    ///\param n is a floating id
-    ///\return the fix id of the new value
-    ///\todo Multiple additions should also be handled.
-    int insert(int n)
-    {
-      if(n>=int(cross.size())) {
-	cross.resize(n+1);
-	if(first_free==-1) {
-	  cross[n]=index.size();
-	  index.push_back(n);
-	}
-	else {
-	  cross[n]=first_free;
-	  int next=index[first_free];
-	  index[first_free]=n;
-	  first_free=next;
-	}
-	return cross[n];
-      }
-      ///\todo Create an own exception type.
-      else throw LogicError(); //floatingId-s must form a continuous range;
-    }
-    ///Remove a fix id.
-
-    ///\param n is a fix id
-    ///
-    void erase(int n) 
-    {
-      int fl=index[n];
-      index[n]=first_free;
-      first_free=n;
-      for(int i=fl+1;i<int(cross.size());++i) {
-	cross[i-1]=cross[i];
-	index[cross[i]]--;
-      }
-      cross.pop_back();
-    }
-    ///An upper bound on the largest fix id.
-
-    ///\todo Do we need this?
-    ///
-    std::size_t maxFixId() { return cross.size()-1; }
-  
-  };
-    
-  ///Common base class for LP solvers
-  class LpSolverBase {
-    
-  public:
-
-    ///\e
-    enum SolveExitStatus {
-      ///\e
-      SOLVED = 0,
-      ///\e
-      UNSOLVED = 1
-    };
-      
-    ///\e
-    enum SolutionStatus {
-      ///Feasible solution has'n been found (but may exist).
-
-      ///\todo NOTFOUND might be a better name.
-      ///
-      UNDEFINED = 0,
-      ///The problem has no feasible solution
-      INFEASIBLE = 1,
-      ///Feasible solution found
-      FEASIBLE = 2,
-      ///Optimal solution exists and found
-      OPTIMAL = 3,
-      ///The cost function is unbounded
-
-      ///\todo Give a feasible solution and an infinite ray (and the
-      ///corresponding bases)
-      INFINITE = 4
-    };
-      
-    ///The floating point type used by the solver
-    typedef double Value;
-    ///The infinity constant
-    static const Value INF;
-    ///The not a number constant
-    static const Value NaN;
-    
-    ///Refer to a column of the LP.
-
-    ///This type is used to refer to a column of the LP.
-    ///
-    ///Its value remains valid and correct even after the addition or erase of
-    ///other columns.
-    ///
-    ///\todo Document what can one do with a Col (INVALID, comparing,
-    ///it is similar to Node/Edge)
-    class Col {
-    protected:
-      int id;
-      friend class LpSolverBase;
-    public:
-      typedef Value ExprValue;
-      typedef True LpSolverCol;
-      Col() {}
-      Col(const Invalid&) : id(-1) {}
-      bool operator<(Col c) const  {return id<c.id;}
-      bool operator==(Col c) const  {return id==c.id;}
-      bool operator!=(Col c) const  {return id==c.id;}
-    };
-
-    ///Refer to a row of the LP.
-
-    ///This type is used to refer to a row of the LP.
-    ///
-    ///Its value remains valid and correct even after the addition or erase of
-    ///other rows.
-    ///
-    ///\todo Document what can one do with a Row (INVALID, comparing,
-    ///it is similar to Node/Edge)
-    class Row {
-    protected:
-      int id;
-      friend class LpSolverBase;
-    public:
-      typedef Value ExprValue;
-      typedef True LpSolverRow;
-      Row() {}
-      Row(const Invalid&) : id(-1) {}
-      typedef True LpSolverRow;
-      bool operator<(Row c) const  {return id<c.id;}
-      bool operator==(Row c) const  {return id==c.id;}
-      bool operator!=(Row c) const  {return id==c.id;} 
-   };
-    
-    ///Linear expression of variables and a constant component
-    
-    ///This data structure strores a linear expression of the variables
-    ///(\ref Col "Col"s) and also has a constant component.
-    ///
-    ///There are several ways to access and modify the contents of this
-    ///container.
-    ///- Its it fully compatible with \c std::map<Col,double>, so for expamle
-    ///if \c e is an Expr and \c v and \c w are of type \ref Col then you can
-    ///read and modify the coefficients like
-    ///these.
-    ///\code
-    ///e[v]=5;
-    ///e[v]+=12;
-    ///e.erase(v);
-    ///\endcode
-    ///or you can also iterate through its elements.
-    ///\code
-    ///double s=0;
-    ///for(LpSolverBase::Expr::iterator i=e.begin();i!=e.end();++i)
-    ///  s+=i->second;
-    ///\endcode
-    ///(This code computes the sum of all coefficients).
-    ///- Numbers (<tt>double</tt>'s)
-    ///and variables (\ref Col "Col"s) directly convert to an
-    ///\ref Expr and the usual linear operations are defined so  
-    ///\code
-    ///v+w
-    ///2*v-3.12*(v-w/2)+2
-    ///v*2.1+(3*v+(v*12+w+6)*3)/2
-    ///\endcode
-    ///are valid expressions. The usual assignment operations are also defined.
-    ///\code
-    ///e=v+w;
-    ///e+=2*v-3.12*(v-w/2)+2;
-    ///e*=3.4;
-    ///e/=5;
-    ///\endcode
-    ///- The constant member can be set and read by \ref constComp()
-    ///\code
-    ///e.constComp()=12;
-    ///double c=e.constComp();
-    ///\endcode
-    ///
-    ///\note that \ref clear() not only sets all coefficients to 0 but also
-    ///clears the constant components.
-    class Expr : public std::map<Col,Value>
-    {
-    public:
-      typedef LpSolverBase::Col Key; 
-      typedef LpSolverBase::Value Value;
-      
-    protected:
-      typedef std::map<Col,Value> Base;
-      
-      Value const_comp;
-  public:
-      typedef True IsLinExpression;
-      ///\e
-      Expr() : Base(), const_comp(0) { }
-      ///\e
-      Expr(const Key &v) : const_comp(0) {
-	Base::insert(std::make_pair(v, 1));
-      }
-      ///\e
-      Expr(const Value &v) : const_comp(v) {}
-      ///\e
-      void set(const Key &v,const Value &c) {
-	Base::insert(std::make_pair(v, c));
-      }
-      ///\e
-      Value &constComp() { return const_comp; }
-      ///\e
-      const Value &constComp() const { return const_comp; }
-      
-      ///Removes the components with zero coefficient.
-      void simplify() {
-	for (Base::iterator i=Base::begin(); i!=Base::end();) {
-	  Base::iterator j=i;
-	  ++j;
-	  if ((*i).second==0) Base::erase(i);
-	  j=i;
-	}
-      }
-
-      ///Sets all coefficients and the constant component to 0.
-      void clear() {
-	Base::clear();
-	const_comp=0;
-      }
-
-      ///\e
-      Expr &operator+=(const Expr &e) {
-	for (Base::const_iterator j=e.begin(); j!=e.end(); ++j)
-	  (*this)[j->first]+=j->second;
-	///\todo it might be speeded up using "hints"
-	const_comp+=e.const_comp;
-	return *this;
-      }
-      ///\e
-      Expr &operator-=(const Expr &e) {
-	for (Base::const_iterator j=e.begin(); j!=e.end(); ++j)
-	  (*this)[j->first]-=j->second;
-	const_comp-=e.const_comp;
-	return *this;
-      }
-      ///\e
-      Expr &operator*=(const Value &c) {
-	for (Base::iterator j=Base::begin(); j!=Base::end(); ++j)
-	  j->second*=c;
-	const_comp*=c;
-	return *this;
-      }
-      ///\e
-      Expr &operator/=(const Value &c) {
-	for (Base::iterator j=Base::begin(); j!=Base::end(); ++j)
-	  j->second/=c;
-	const_comp/=c;
-	return *this;
-      }
-    };
-    
-    ///Linear constraint
-    //typedef LinConstr<Expr> Constr;
-    class Constr
-    {
-    public:
-      typedef LpSolverBase::Expr Expr;
-      typedef Expr::Key Key;
-      typedef Expr::Value Value;
-      
-      static const Value INF;
-      static const Value NaN;
-      //     static const Value INF=0;
-      //     static const Value NaN=1;
-      
-    protected:
-      Expr _expr;
-      Value _lb,_ub;
-    public:
-      ///\e
-      Constr() : _expr(), _lb(NaN), _ub(NaN) {}
-      ///\e
-      Constr(Value lb,const Expr &e,Value ub) :
-	_expr(e), _lb(lb), _ub(ub) {}
-      ///\e
-      Constr(const Expr &e,Value ub) : 
-	_expr(e), _lb(NaN), _ub(ub) {}
-      ///\e
-      Constr(Value lb,const Expr &e) :
-	_expr(e), _lb(lb), _ub(NaN) {}
-      ///\e
-      Constr(const Expr &e) : 
-	_expr(e), _lb(NaN), _ub(NaN) {}
-      ///\e
-      void clear() 
-      {
-	_expr.clear();
-	_lb=_ub=NaN;
-      }
-      ///\e
-      Expr &expr() { return _expr; }
-      ///\e
-      const Expr &expr() const { return _expr; }
-      ///\e
-      Value &lowerBound() { return _lb; }
-      ///\e
-      const Value &lowerBound() const { return _lb; }
-      ///\e
-      Value &upperBound() { return _ub; }
-      ///\e
-      const Value &upperBound() const { return _ub; }
-      ///\e
-      bool lowerBounded() const { 
-	using namespace std;
-	return isfinite(_lb);
-      }
-      ///\e
-      bool upperBounded() const {
-	using namespace std;
-	return isfinite(_ub);
-      }
-    };
-    
-
-  protected:
-    _FixId rows;
-    _FixId cols;
-
-    virtual int _addCol() = 0;
-    virtual int _addRow() = 0;
-    virtual void _setRowCoeffs(int i, 
-			       int length,
-                               int  const * indices, 
-                               Value  const * values ) = 0;
-    virtual void _setColCoeffs(int i, 
-			       int length,
-                               int  const * indices, 
-                               Value  const * values ) = 0;
-    virtual void _setColLowerBound(int i, Value value) = 0;
-    virtual void _setColUpperBound(int i, Value value) = 0;
-    virtual void _setRowLowerBound(int i, Value value) = 0;
-    virtual void _setRowUpperBound(int i, Value value) = 0;
-    virtual void _setObjCoeff(int i, Value obj_coef) = 0;
-    virtual SolveExitStatus _solve() = 0;
-    virtual Value _getPrimal(int i) = 0;
-    virtual SolutionStatus _getPrimalType() = 0;
-
-
-    void clearObj() {}
-  public:
-
-
-    ///\e
-    virtual ~LpSolverBase() {}
-
-    ///\name Build up and modify of the LP
-
-    ///@{
-
-    ///Add a new empty column (i.e a new variable) to the LP
-    Col addCol() { Col c; c.id=cols.insert(_addCol()); return c;}
-
-    ///\brief Adds several new columns
-    ///(i.e a variables) at once
-    ///
-    ///This magic function takes a container as its argument
-    ///and fills its elements
-    ///with new columns (i.e. variables)
-    ///\param t can be
-    ///- a standard STL compatible iterable container with
-    ///\ref Col as its \c values_type
-    ///like
-    ///\code
-    ///std::vector<LpSolverBase::Col>
-    ///std::list<LpSolverBase::Col>
-    ///\endcode
-    ///- a standard STL compatible iterable container with
-    ///\ref Col as its \c mapped_type
-    ///like
-    ///\code
-    ///std::map<AnyType,LpSolverBase::Col>
-    ///\endcode
-    ///- an iterable lemon \ref concept::WriteMap "write map" like 
-    ///\code
-    ///ListGraph::NodeMap<LpSolverBase::Col>
-    ///ListGraph::EdgeMap<LpSolverBase::Col>
-    ///\endcode
-    ///\return The number of the created column.
-    ///\bug Iterable nodemap hasn't been implemented yet.
-#ifdef DOXYGEN
-    template<class T>
-    int addColSet(T &t) { return 0;} 
-#else
-    template<class T>
-    typename enable_if<typename T::value_type::LpSolverCol,int>::type
-    addColSet(T &t,dummy<0> = 0) {
-      int s=0;
-      for(typename T::iterator i=t.begin();i!=t.end();++i) {*i=addCol();s++;}
-      return s;
-    }
-    template<class T>
-    typename enable_if<typename T::value_type::second_type::LpSolverCol,
-		       int>::type
-    addColSet(T &t,dummy<1> = 1) { 
-      int s=0;
-      for(typename T::iterator i=t.begin();i!=t.end();++i) {
-	i->second=addCol();
-	s++;
-      }
-      return s;
-    }
-    template<class T>
-    typename enable_if<typename T::ValueSet::value_type::LpSolverCol,
-		       int>::type
-    addColSet(T &t,dummy<2> = 2) { 
-      ///\bug <tt>return addColSet(t.valueSet());</tt> should also work.
-      int s=0;
-      for(typename T::ValueSet::iterator i=t.valueSet().begin();
-	  i!=t.valueSet().end();
-	  ++i)
-	{
-	  *i=addCol();
-	  s++;
-	}
-      return s;
-    }
-#endif
-
-    ///Add a new empty row (i.e a new constaint) to the LP
-
-    ///This function adds a new empty row (i.e a new constaint) to the LP.
-    ///\return The created row
-    Row addRow() { Row r; r.id=rows.insert(_addRow()); return r;}
-
-    ///Set a row (i.e a constaint) of the LP
-
-    ///\param r is the row to be modified
-    ///\param l is lower bound (-\ref INF means no bound)
-    ///\param e is a linear expression (see \ref Expr)
-    ///\param u is the upper bound (\ref INF means no bound)
-    ///\bug This is a temportary function. The interface will change to
-    ///a better one.
-    void setRow(Row r, Value l,const Expr &e, Value u) {
-      std::vector<int> indices;
-      std::vector<Value> values;
-      indices.push_back(0);
-      values.push_back(0);
-      for(Expr::const_iterator i=e.begin(); i!=e.end(); ++i)
-	if((*i).second!=0) { ///\bug EPSILON would be necessary here!!!
-	  indices.push_back(cols.floatingId((*i).first.id));
-	  values.push_back((*i).second);
-	}
-      _setRowCoeffs(rows.floatingId(r.id),indices.size()-1,
-		    &indices[0],&values[0]);
-      _setRowLowerBound(rows.floatingId(r.id),l-e.constComp());
-      _setRowUpperBound(rows.floatingId(r.id),u-e.constComp());
-    }
-
-    ///Set a row (i.e a constaint) of the LP
-
-    ///\param r is the row to be modified
-    ///\param c is a linear expression (see \ref Constr)
-    void setRow(Row r, const Constr &c) {
-      setRow(r,
-	     c.lowerBounded()?c.lowerBound():-INF,
-	     c.expr(),
-	     c.upperBounded()?c.upperBound():INF);
-    }
-
-    ///Add a new row (i.e a new constaint) to the LP
-
-    ///\param l is the lower bound (-\ref INF means no bound)
-    ///\param e is a linear expression (see \ref Expr)
-    ///\param u is the upper bound (\ref INF means no bound)
-    ///\return The created row.
-    ///\bug This is a temportary function. The interface will change to
-    ///a better one.
-    Row addRow(Value l,const Expr &e, Value u) {
-      Row r=addRow();
-      setRow(r,l,e,u);
-      return r;
-    }
-
-    ///Add a new row (i.e a new constaint) to the LP
-
-    ///\param c is a linear expression (see \ref Constr)
-    ///\return The created row.
-    Row addRow(const Constr &c) {
-      Row r=addRow();
-      setRow(r,c);
-      return r;
-    }
-
-    /// Set the lower bound of a column (i.e a variable)
-
-    /// The upper bound of a variable (column) has to be given by an 
-    /// extended number of type Value, i.e. a finite number of type 
-    /// Value or -\ref INF.
-    void colLowerBound(Col c, Value value) {
-      _setColLowerBound(cols.floatingId(c.id),value);
-    }
-    /// Set the upper bound of a column (i.e a variable)
-
-    /// The upper bound of a variable (column) has to be given by an 
-    /// extended number of type Value, i.e. a finite number of type 
-    /// Value or \ref INF.
-    void colUpperBound(Col c, Value value) {
-      _setColUpperBound(cols.floatingId(c.id),value);
-    };
-    /// Set the lower and the upper bounds of a column (i.e a variable)
-
-    /// The lower and the upper bounds of
-    /// a variable (column) have to be given by an 
-    /// extended number of type Value, i.e. a finite number of type 
-    /// Value, -\ref INF or \ref INF.
-    void colBounds(Col c, Value lower, Value upper) {
-      _setColLowerBound(cols.floatingId(c.id),lower);
-      _setColUpperBound(cols.floatingId(c.id),upper);
-    }
-    
-    /// Set the lower bound of a row (i.e a constraint)
-
-    /// The lower bound of a linear expression (row) has to be given by an 
-    /// extended number of type Value, i.e. a finite number of type 
-    /// Value or -\ref INF.
-    void rowLowerBound(Row r, Value value) {
-      _setRowLowerBound(rows.floatingId(r.id),value);
-    };
-    /// Set the upper bound of a row (i.e a constraint)
-
-    /// The upper bound of a linear expression (row) has to be given by an 
-    /// extended number of type Value, i.e. a finite number of type 
-    /// Value or \ref INF.
-    void rowUpperBound(Row r, Value value) {
-      _setRowUpperBound(rows.floatingId(r.id),value);
-    };
-    /// Set the lower and the upper bounds of a row (i.e a variable)
-
-    /// The lower and the upper bounds of
-    /// a constraint (row) have to be given by an 
-    /// extended number of type Value, i.e. a finite number of type 
-    /// Value, -\ref INF or \ref INF.
-    void rowBounds(Row c, Value lower, Value upper) {
-      _setRowLowerBound(rows.floatingId(c.id),lower);
-      _setRowUpperBound(rows.floatingId(c.id),upper);
-    }
-    
-    ///Set an element of the objective function
-    void objCoeff(Col c, Value v) {_setObjCoeff(cols.floatingId(c.id),v); };
-    ///Set the objective function
-    
-    ///\param e is a linear expression of type \ref Expr.
-    ///\todo What to do with the constant component?
-    void setObj(Expr e) {
-      clearObj();
-      for (Expr::iterator i=e.begin(); i!=e.end(); ++i)
-	objCoeff((*i).first,(*i).second);
-    }
-
-    ///@}
-
-
-    ///\name Solve the LP
-
-    ///@{
-
-    ///\e
-    SolveExitStatus solve() { return _solve(); }
-    
-    ///@}
-    
-    ///\name Obtain the solution
-
-    ///@{
-
-    ///\e
-    SolutionStatus primalType() {
-      return _getPrimalType();
-    }
-
-    ///\e
-    Value primal(Col c) { return _getPrimal(cols.floatingId(c.id)); }
-
-    ///@}
-    
-  };  
-
-  ///\e
-  
-  ///\relates LpSolverBase::Expr
-  ///
-  inline LpSolverBase::Expr operator+(const LpSolverBase::Expr &a,
-				      const LpSolverBase::Expr &b) 
-  {
-    LpSolverBase::Expr tmp(a);
-    tmp+=b; ///\todo Don't STL have some special 'merge' algorithm?
-    return tmp;
-  }
-  ///\e
-  
-  ///\relates LpSolverBase::Expr
-  ///
-  inline LpSolverBase::Expr operator-(const LpSolverBase::Expr &a,
-				      const LpSolverBase::Expr &b) 
-  {
-    LpSolverBase::Expr tmp(a);
-    tmp-=b; ///\todo Don't STL have some special 'merge' algorithm?
-    return tmp;
-  }
-  ///\e
-  
-  ///\relates LpSolverBase::Expr
-  ///
-  inline LpSolverBase::Expr operator*(const LpSolverBase::Expr &a,
-				      const LpSolverBase::Value &b) 
-  {
-    LpSolverBase::Expr tmp(a);
-    tmp*=b; ///\todo Don't STL have some special 'merge' algorithm?
-    return tmp;
-  }
-  
-  ///\e
-  
-  ///\relates LpSolverBase::Expr
-  ///
-  inline LpSolverBase::Expr operator*(const LpSolverBase::Value &a,
-				      const LpSolverBase::Expr &b) 
-  {
-    LpSolverBase::Expr tmp(b);
-    tmp*=a; ///\todo Don't STL have some special 'merge' algorithm?
-    return tmp;
-  }
-  ///\e
-  
-  ///\relates LpSolverBase::Expr
-  ///
-  inline LpSolverBase::Expr operator/(const LpSolverBase::Expr &a,
-				      const LpSolverBase::Value &b) 
-  {
-    LpSolverBase::Expr tmp(a);
-    tmp/=b; ///\todo Don't STL have some special 'merge' algorithm?
-    return tmp;
-  }
-  
-  ///\e
-  
-  ///\relates LpSolverBase::Constr
-  ///
-  inline LpSolverBase::Constr operator<=(const LpSolverBase::Expr &e,
-					 const LpSolverBase::Expr &f) 
-  {
-    return LpSolverBase::Constr(-LpSolverBase::INF,e-f,0);
-  }
-
-  ///\e
-  
-  ///\relates LpSolverBase::Constr
-  ///
-  inline LpSolverBase::Constr operator<=(const LpSolverBase::Value &e,
-					 const LpSolverBase::Expr &f) 
-  {
-    return LpSolverBase::Constr(e,f);
-  }
-
-  ///\e
-  
-  ///\relates LpSolverBase::Constr
-  ///
-  inline LpSolverBase::Constr operator<=(const LpSolverBase::Expr &e,
-					 const LpSolverBase::Value &f) 
-  {
-    return LpSolverBase::Constr(e,f);
-  }
-
-  ///\e
-  
-  ///\relates LpSolverBase::Constr
-  ///
-  inline LpSolverBase::Constr operator>=(const LpSolverBase::Expr &e,
-					 const LpSolverBase::Expr &f) 
-  {
-    return LpSolverBase::Constr(-LpSolverBase::INF,f-e,0);
-  }
-
-
-  ///\e
-  
-  ///\relates LpSolverBase::Constr
-  ///
-  inline LpSolverBase::Constr operator>=(const LpSolverBase::Value &e,
-					 const LpSolverBase::Expr &f) 
-  {
-    return LpSolverBase::Constr(f,e);
-  }
-
-
-  ///\e
-  
-  ///\relates LpSolverBase::Constr
-  ///
-  inline LpSolverBase::Constr operator>=(const LpSolverBase::Expr &e,
-					 const LpSolverBase::Value &f) 
-  {
-    return LpSolverBase::Constr(f,e);
-  }
-
-  ///\e
-  
-  ///\relates LpSolverBase::Constr
-  ///
-  inline LpSolverBase::Constr operator==(const LpSolverBase::Expr &e,
-					 const LpSolverBase::Expr &f) 
-  {
-    return LpSolverBase::Constr(0,e-f,0);
-  }
-
-  ///\e
-  
-  ///\relates LpSolverBase::Constr
-  ///
-  inline LpSolverBase::Constr operator<=(const LpSolverBase::Value &n,
-					 const LpSolverBase::Constr&c) 
-  {
-    LpSolverBase::Constr tmp(c);
-    ///\todo Create an own exception type.
-    if(!isnan(tmp.lowerBound())) throw LogicError();
-    else tmp.lowerBound()=n;
-    return tmp;
-  }
-  ///\e
-  
-  ///\relates LpSolverBase::Constr
-  ///
-  inline LpSolverBase::Constr operator<=(const LpSolverBase::Constr& c,
-					 const LpSolverBase::Value &n)
-  {
-    LpSolverBase::Constr tmp(c);
-    ///\todo Create an own exception type.
-    if(!isnan(tmp.upperBound())) throw LogicError();
-    else tmp.upperBound()=n;
-    return tmp;
-  }
-
-  ///\e
-  
-  ///\relates LpSolverBase::Constr
-  ///
-  inline LpSolverBase::Constr operator>=(const LpSolverBase::Value &n,
-					 const LpSolverBase::Constr&c) 
-  {
-    LpSolverBase::Constr tmp(c);
-    ///\todo Create an own exception type.
-    if(!isnan(tmp.upperBound())) throw LogicError();
-    else tmp.upperBound()=n;
-    return tmp;
-  }
-  ///\e
-  
-  ///\relates LpSolverBase::Constr
-  ///
-  inline LpSolverBase::Constr operator>=(const LpSolverBase::Constr& c,
-					 const LpSolverBase::Value &n)
-  {
-    LpSolverBase::Constr tmp(c);
-    ///\todo Create an own exception type.
-    if(!isnan(tmp.lowerBound())) throw LogicError();
-    else tmp.lowerBound()=n;
-    return tmp;
-  }
-
-
-} //namespace lemon
-
-#endif //LEMON_LP_BASE_H
diff -r c9c2e90b2342 -r c3dc75d4af24 src/work/athos/lp/lp_glpk.cc
--- a/src/work/athos/lp/lp_glpk.cc	Tue Apr 05 08:43:51 2005 +0000
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,288 +0,0 @@
-/* -*- C++ -*-
- * src/lemon/lp_glpk.cc - Part of LEMON, a generic C++ optimization library
- *
- * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
- * (Egervary Combinatorial Optimization Research Group, EGRES).
- *
- * Permission to use, modify and distribute this software is granted
- * provided that this copyright notice appears in all copies. For
- * precise terms see the accompanying LICENSE file.
- *
- * This software is provided "AS IS" with no warranty of any kind,
- * express or implied, and with no claim as to its suitability for any
- * purpose.
- *
- */
-
-#ifndef LEMON_LP_GLPK_CC
-#define LEMON_LP_GLPK_CC
-
-///\file
-///\brief Implementation of the LEMON-GLPK lp solver interface.
-
-#include "lp_glpk.h"
-
-namespace lemon {
-
-    /// \e
-    int LpGlpk::_addCol() { 
-	int i=lpx_add_cols(lp, 1);
-	_setColLowerBound(i, -INF);
-	_setColUpperBound(i, INF);
-	return i;
-    }
-
-    /// \e
-    int LpGlpk::_addRow() { 
-	int i=lpx_add_rows(lp, 1);
-	return i;
-    }
-
-  
-    void LpGlpk::_setRowCoeffs(int i, 
-			       int length,
-			       const int   * indices, 
-			       const Value   * values )
-    {
-      lpx_set_mat_row(lp, i, length,
-		      const_cast<int * >(indices) ,
-		      const_cast<Value * >(values));
-    }
-  
-    void LpGlpk::_setColCoeffs(int i, 
-			       int length,
-			       const int   * indices, 
-			       const Value   * values)
-    {
-      lpx_set_mat_col(lp, i, length,
-		      const_cast<int * >(indices),
-		      const_cast<Value * >(values));
-    }
-  
-    void LpGlpk::_setColLowerBound(int i, Value lo)
-    {
-      if (lo==INF) {
-	//FIXME error
-      }
-      int b=lpx_get_col_type(lp, i);
-      double up=lpx_get_col_ub(lp, i);	
-      if (lo==-INF) {
-	switch (b) {
-	case LPX_FR:
-	case LPX_LO:
-	  lpx_set_col_bnds(lp, i, LPX_FR, lo, up);
-	  break;
-	case LPX_UP:
-	  break;
-	case LPX_DB:
-	case LPX_FX:
-	  lpx_set_col_bnds(lp, i, LPX_UP, lo, up);
-	  break;
-	default: ;
-	  //FIXME error
-	}
-      } else {
-	switch (b) {
-	case LPX_FR:
-	case LPX_LO:
-	  lpx_set_col_bnds(lp, i, LPX_LO, lo, up);
-	  break;
-	case LPX_UP:	  
-	case LPX_DB:
-	case LPX_FX:
-	  if (lo==up) 
-	    lpx_set_col_bnds(lp, i, LPX_FX, lo, up);
-	  else 
-	    lpx_set_col_bnds(lp, i, LPX_DB, lo, up);
-	  break;
-	default: ;
-	  //FIXME error
-	}
-      }
-
-    }
-  
-    void LpGlpk::_setColUpperBound(int i, Value up)
-    {
-      if (up==-INF) {
-	//FIXME error
-      }
-      int b=lpx_get_col_type(lp, i);
-      double lo=lpx_get_col_lb(lp, i);
-      if (up==INF) {
-	switch (b) {
-	case LPX_FR:
-	case LPX_LO:
-	  break;
-	case LPX_UP:
-	  lpx_set_col_bnds(lp, i, LPX_FR, lo, up);
-	  break;
-	case LPX_DB:
-	case LPX_FX:
-	  lpx_set_col_bnds(lp, i, LPX_LO, lo, up);
-	  break;
-	default: ;
-	  //FIXME error
-	}
-      } else {
-	switch (b) {
-	case LPX_FR:
-	  lpx_set_col_bnds(lp, i, LPX_UP, lo, up);
-	  break;
-	case LPX_UP:
-	  lpx_set_col_bnds(lp, i, LPX_UP, lo, up);
-	  break;
-	case LPX_LO:
-	case LPX_DB:
-	case LPX_FX:
-	  if (lo==up) 
-	    lpx_set_col_bnds(lp, i, LPX_FX, lo, up);
-	  else 
-	    lpx_set_col_bnds(lp, i, LPX_DB, lo, up);
-	  break;
-	default: ;
-	  //FIXME error
-	}
-      }
-    }
-  
-    void LpGlpk::_setRowLowerBound(int i, Value lo)
-    {
-      if (lo==INF) {
-	//FIXME error
-      }
-      int b=lpx_get_row_type(lp, i);
-      double up=lpx_get_row_ub(lp, i);	
-      if (lo==-INF) {
-	switch (b) {
-	case LPX_FR:
-	case LPX_LO:
-	  lpx_set_row_bnds(lp, i, LPX_FR, lo, up);
-	  break;
-	case LPX_UP:
-	  break;
-	case LPX_DB:
-	case LPX_FX:
-	  lpx_set_row_bnds(lp, i, LPX_UP, lo, up);
-	  break;
-	default: ;
-	  //FIXME error
-	}
-      } else {
-	switch (b) {
-	case LPX_FR:
-	case LPX_LO:
-	  lpx_set_row_bnds(lp, i, LPX_LO, lo, up);
-	  break;
-	case LPX_UP:	  
-	case LPX_DB:
-	case LPX_FX:
-	  if (lo==up) 
-	    lpx_set_row_bnds(lp, i, LPX_FX, lo, up);
-	  else 
-	    lpx_set_row_bnds(lp, i, LPX_DB, lo, up);
-	  break;
-	default: ;
-	  //FIXME error
-	}
-      }
-    }
-  
-  void LpGlpk::_setRowUpperBound(int i, Value up)
-  {
-    if (up==-INF) {
-      //FIXME error
-    }
-    int b=lpx_get_row_type(lp, i);
-    double lo=lpx_get_row_lb(lp, i);
-    if (up==INF) {
-      switch (b) {
-      case LPX_FR:
-      case LPX_LO:
-	break;
-      case LPX_UP:
-	lpx_set_row_bnds(lp, i, LPX_FR, lo, up);
-	break;
-      case LPX_DB:
-      case LPX_FX:
-	lpx_set_row_bnds(lp, i, LPX_LO, lo, up);
-	break;
-      default: ;
-	//FIXME error
-      }
-    } else {
-      switch (b) {
-      case LPX_FR:
-	lpx_set_row_bnds(lp, i, LPX_UP, lo, up);
-	break;
-      case LPX_UP:
-	lpx_set_row_bnds(lp, i, LPX_UP, lo, up);
-	break;
-      case LPX_LO:
-      case LPX_DB:
-      case LPX_FX:
-	if (lo==up) 
-	  lpx_set_row_bnds(lp, i, LPX_FX, lo, up);
-	else 
-	  lpx_set_row_bnds(lp, i, LPX_DB, lo, up);
-	break;
-      default: ;
-	//FIXME error
-      }
-    }
-  }
-  
-  void LpGlpk::_setObjCoeff(int i, Value obj_coef)
-  {
-    lpx_set_obj_coef(lp, i, obj_coef);
-  }
-
-
-  LpGlpk::SolveExitStatus LpGlpk::_solve()
-  {
-    int i=  lpx_simplex(lp);
-    switch (i) {
-    case LPX_E_OK: 
-      return SOLVED;
-      break;
-    default:
-      return UNSOLVED;
-    }
-  }
-
-  LpGlpk::Value LpGlpk::_getPrimal(int i)
-  {
-    return lpx_get_col_prim(lp,i);
-  }
-  
- 
-  LpGlpk::SolutionStatus LpGlpk::_getPrimalType()
-  {
-    int stat=  lpx_get_status(lp);
-    switch (stat) {
-    case LPX_UNDEF://Undefined (no solve has been run yet)
-      return UNDEFINED;
-      break;
-    case LPX_NOFEAS://There is no feasible solution (primal, I guess)
-    case LPX_INFEAS://Infeasible 
-      return INFEASIBLE;
-      break;
-    case LPX_UNBND://Unbounded
-      return INFINITE;
-      break;
-    case LPX_FEAS://Feasible
-      return FEASIBLE;
-      break;
-    case LPX_OPT://Feasible
-      return OPTIMAL;
-      break;
-    default:
-      return UNDEFINED; //to avoid gcc warning
-      //FIXME error
-    }
-  }
-
-
-} //END OF NAMESPACE LEMON
-
-#endif //LEMON_LP_GLPK_CC
diff -r c9c2e90b2342 -r c3dc75d4af24 src/work/athos/lp/lp_glpk.h
--- a/src/work/athos/lp/lp_glpk.h	Tue Apr 05 08:43:51 2005 +0000
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,89 +0,0 @@
-/* -*- C++ -*-
- * src/lemon/lp_glpk.h - Part of LEMON, a generic C++ optimization library
- *
- * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
- * (Egervary Combinatorial Optimization Research Group, EGRES).
- *
- * Permission to use, modify and distribute this software is granted
- * provided that this copyright notice appears in all copies. For
- * precise terms see the accompanying LICENSE file.
- *
- * This software is provided "AS IS" with no warranty of any kind,
- * express or implied, and with no claim as to its suitability for any
- * purpose.
- *
- */
-
-#ifndef LEMON_LP_GLPK_H
-#define LEMON_LP_GLPK_H
-
-///\file
-///\brief Header of the LEMON-GLPK lp solver interface.
-
-#include "lp_base.h"
-extern "C" {
-#include "glpk.h"
-}
-
-namespace lemon {
-
-
-  /// \brief Wrapper for GLPK solver
-  /// 
-  /// This class implements a lemon wrapper for GLPK.
-  class LpGlpk : public LpSolverBase {
-
-  public:
-
-    typedef LpSolverBase Parent;
-    
-    /// \e
-    LPX* lp;
-
-    /// \e
-    LpGlpk() : Parent(), 
-			lp(lpx_create_prob()) {
-      lpx_set_int_parm(lp, LPX_K_DUAL, 1);
-    }
-    /// \e
-    ~LpGlpk() {
-      lpx_delete_prob(lp);
-    }
-
-  protected:
-    virtual int _addCol();
-    virtual int _addRow();
-    virtual void _setRowCoeffs(int i, 
-			       int length,
-                               const int   * indices, 
-                               const Value   * values );
-    virtual void _setColCoeffs(int i, 
-			       int length,
-                               const int   * indices, 
-                               const Value   * values);
-    virtual void _setColLowerBound(int i, Value value);
-    virtual void _setColUpperBound(int i, Value value);
-    virtual void _setRowLowerBound(int i, Value value);
-    virtual void _setRowUpperBound(int i, Value value);
-    virtual void _setObjCoeff(int i, Value obj_coef);
-    ///\e
-    
-    ///\bug Unimplemented
-    ///
-    virtual SolveExitStatus _solve();
-    ///\e
-    
-    ///\bug Unimplemented
-    ///
-    virtual Value _getPrimal(int i);
-    ///\e
-    
-    ///\bug Unimplemented
-    ///
-    virtual SolutionStatus _getPrimalType();
-
-  };
-} //END OF NAMESPACE LEMON
-
-#endif //LEMON_LP_GLPK_H
-
diff -r c9c2e90b2342 -r c3dc75d4af24 src/work/athos/lp/lp_solver_skeleton.cc
--- a/src/work/athos/lp/lp_solver_skeleton.cc	Tue Apr 05 08:43:51 2005 +0000
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,84 +0,0 @@
-/* -*- C++ -*-
- * src/lemon/lp_solver_skeleton.cc
- * - Part of LEMON, a generic C++ optimization library
- *
- * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
- * (Egervary Combinatorial Optimization Research Group, EGRES).
- *
- * Permission to use, modify and distribute this software is granted
- * provided that this copyright notice appears in all copies. For
- * precise terms see the accompanying LICENSE file.
- *
- * This software is provided "AS IS" with no warranty of any kind,
- * express or implied, and with no claim as to its suitability for any
- * purpose.
- *
- */
-
-#include"lp_solver_skeleton.h"
-
-///\file
-///\brief A skeleton file to implement LP solver interfaces
-namespace lemon {
-  
-  int LpSolverSkeleton::_addCol()
-  {
-    return ++col_num;
-  }
-  
-  int LpSolverSkeleton::_addRow() 
-  {
-    return ++row_num;
-  }
-  
-  void LpSolverSkeleton::_setRowCoeffs(int i, 
-					       int length,
-					       int  const * indices, 
-					       Value  const * values )
-  {
-  }
-  
-  void LpSolverSkeleton::_setColCoeffs(int i, 
-					       int length,
-					       int  const * indices, 
-					       Value  const * values)
-  {
-  }
-  
-  void LpSolverSkeleton::_setColLowerBound(int i, Value value)
-  {
-  }
-  
-  void LpSolverSkeleton::_setColUpperBound(int i, Value value)
-  {
-  }
-  
-  void LpSolverSkeleton::_setRowLowerBound(int i, Value value)
-  {
-  }
-  
-  void LpSolverSkeleton::_setRowUpperBound(int i, Value value)
-  {
-  }
-  
-  void LpSolverSkeleton::_setObjCoeff(int i, Value obj_coef)
-  {
-  }
-
-  LpSolverSkeleton::SolveExitStatus LpSolverSkeleton::_solve()
-  {
-    return SOLVED;
-  }
-
-  LpSolverSkeleton::Value LpSolverSkeleton::_getPrimal(int i)
-  {
-    return 0;
-  }
-  
-  LpSolverSkeleton::SolutionStatus LpSolverSkeleton::_getPrimalType()
-  {
-    return OPTIMAL;
-  }
-  
-} //namespace lemon
-
diff -r c9c2e90b2342 -r c3dc75d4af24 src/work/athos/lp/lp_solver_skeleton.h
--- a/src/work/athos/lp/lp_solver_skeleton.h	Tue Apr 05 08:43:51 2005 +0000
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,104 +0,0 @@
-/* -*- C++ -*-
- * src/lemon/lp_solver_skeleton.h
- * - Part of LEMON, a generic C++ optimization library
- *
- * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
- * (Egervary Combinatorial Optimization Research Group, EGRES).
- *
- * Permission to use, modify and distribute this software is granted
- * provided that this copyright notice appears in all copies. For
- * precise terms see the accompanying LICENSE file.
- *
- * This software is provided "AS IS" with no warranty of any kind,
- * express or implied, and with no claim as to its suitability for any
- * purpose.
- *
- */
-
-#ifndef LEMON_LP_SOLVER_SKELETON
-#define LEMON_LP_SOLVER_SKELETON
-
-#include"lp_base.h"
-
-///\file
-///\brief A skeleton file to implement LP solver interfaces
-namespace lemon {
-  
-  ///A skeleton class to implement LP solver interfaces
-  class LpSolverSkeleton :public LpSolverBase {
-    int col_num,row_num;
-    
-  protected:
-    /// \e
-    virtual int _addCol();
-    /// \e
-    virtual int _addRow();
-    /// \e
-
-    /// \warning Arrays are indexed from 1 (datum at index 0 is ignored)
-    ///
-    virtual void _setRowCoeffs(int i, 
-			       int length,
-                               int  const * indices, 
-                               Value  const * values );
-    /// \e
-
-    /// \warning Arrays are indexed from 1 (datum at index 0 is ignored)
-    ///
-    virtual void _setColCoeffs(int i, 
-			       int length,
-                               int  const * indices, 
-                               Value  const * values );
-    
-    /// \e
-
-    /// The lower bound of a variable (column) have to be given by an 
-    /// extended number of type Value, i.e. a finite number of type 
-    /// Value or -\ref INF.
-    virtual void _setColLowerBound(int i, Value value);
-    /// \e
-
-    /// The upper bound of a variable (column) have to be given by an 
-    /// extended number of type Value, i.e. a finite number of type 
-    /// Value or \ref INF.
-    virtual void _setColUpperBound(int i, Value value);
-    /// \e
-
-    /// The lower bound of a linear expression (row) have to be given by an 
-    /// extended number of type Value, i.e. a finite number of type 
-    /// Value or -\ref INF.
-    virtual void _setRowLowerBound(int i, Value value);
-    /// \e
-
-    /// The upper bound of a linear expression (row) have to be given by an 
-    /// extended number of type Value, i.e. a finite number of type 
-    /// Value or \ref INF.
-    virtual void _setRowUpperBound(int i, Value value);
-
-    /// \e
-    virtual void _setObjCoeff(int i, Value obj_coef);
-
-    ///\e
-    
-    ///\bug Wrong interface
-    ///
-    virtual SolveExitStatus _solve();
-
-    ///\e
-
-    ///\bug Wrong interface
-    ///
-    virtual Value _getPrimal(int i);
-    ///\e
-
-    ///\bug Wrong interface
-    ///
-    virtual SolutionStatus _getPrimalType();
-
-  public:
-    LpSolverSkeleton() : LpSolverBase(), col_num(0), row_num(0) {}
-  };  
-
-} //namespace lemon
-
-#endif // LEMON_LP_SOLVER_SKELETON