1.1 --- a/src/work/athos/lp/lin_expr.h	Fri Mar 25 16:19:03 2005 +0000
     1.2 +++ b/src/work/athos/lp/lin_expr.h	Fri Mar 25 18:56:07 2005 +0000
     1.3 @@ -18,10 +18,8 @@
     1.4  #define LEMON_LIN_EXPR_H
     1.5  
     1.6  #include<vector>
     1.7 -
     1.8 -
     1.9  #include<map>
    1.10 -
    1.11 +#include<lemon/utility.h>
    1.12  ///\file
    1.13  ///\brief Classes to handle linear expressions
    1.14  namespace lemon {
    1.15 @@ -39,6 +37,7 @@
    1.16  
    1.17      Coeff const_comp;
    1.18    public:
    1.19 +    typedef True IsLinExpression;
    1.20      ///\e
    1.21      SparseLinExpr() : Base(), const_comp(0) { }
    1.22      ///\e
    1.23 @@ -262,6 +261,50 @@
    1.24    ///\relates SparseLinExpr
    1.25    ///
    1.26    template <class V>
    1.27 +  SparseLinExpr<V> operator+(const V &v,const typename V::ExprValue &c) {
    1.28 +    SparseLinExpr<V> tmp(v);
    1.29 +    tmp.constComp()=c;
    1.30 +    return tmp;
    1.31 +  }
    1.32 +
    1.33 +  ///\e
    1.34 +  
    1.35 +  ///\relates SparseLinExpr
    1.36 +  ///
    1.37 +  template <class V>
    1.38 +  SparseLinExpr<V> operator-(const V &v,const typename V::ExprValue &c) {
    1.39 +    SparseLinExpr<V> tmp(v);
    1.40 +    tmp.constComp()=-c;
    1.41 +    return tmp;
    1.42 +  }
    1.43 +
    1.44 +  ///\e
    1.45 +  
    1.46 +  ///\relates SparseLinExpr
    1.47 +  ///
    1.48 +  template <class V>
    1.49 +  SparseLinExpr<V> operator+(const typename V::ExprValue &c,const V &v) {
    1.50 +    SparseLinExpr<V> tmp(v);
    1.51 +    tmp.constComp()=c;
    1.52 +    return tmp;
    1.53 +  }
    1.54 +
    1.55 +  ///\e
    1.56 +  
    1.57 +  ///\relates SparseLinExpr
    1.58 +  ///
    1.59 +  template <class V>
    1.60 +  SparseLinExpr<V> operator-(const typename V::ExprValue &c,const V &v) {
    1.61 +    SparseLinExpr<V> tmp(c);
    1.62 +    tmp[v]=-1;
    1.63 +    return tmp;
    1.64 +  }
    1.65 +
    1.66 +  ///\e
    1.67 +  
    1.68 +  ///\relates SparseLinExpr
    1.69 +  ///
    1.70 +  template <class V>
    1.71    SparseLinExpr<V> operator+(const V &v1,const V &v2) {
    1.72      SparseLinExpr<V> tmp(v1);
    1.73      tmp[v2]+=1;
    1.74 @@ -302,6 +345,154 @@
    1.75    }
    1.76  
    1.77  
    1.78 +  //////////////////////////////////////////////////////////////////////
    1.79 +  /// Constraints
    1.80 +  //////////////////////////////////////////////////////////////////////
    1.81 +  
    1.82 +  template <class E>
    1.83 +  class LinConstr
    1.84 +  {
    1.85 +  public:
    1.86 +    typedef E Expr;
    1.87 +    typedef typename E::Var Var;
    1.88 +    typedef typename E::Coeff Coeff;
    1.89 +    
    1.90 +    static const Coeff INF;
    1.91 +    static const Coeff NaN;
    1.92 +//     static const Coeff INF=0;
    1.93 +//     static const Coeff NaN=1;
    1.94 +
    1.95 +    Expr expr;
    1.96 +    Coeff lb,ub;
    1.97 +    
    1.98 +    LinConstr() : expr(), lb(NaN), ub(NaN) {}
    1.99 +    LinConstr(Coeff _lb,const Expr &e,Coeff _ub) :
   1.100 +      expr(e), lb(_lb), ub(_ub) {}
   1.101 +    LinConstr(const Expr &e,Coeff _ub) : 
   1.102 +      expr(e), lb(NaN), ub(_ub) {}
   1.103 +    LinConstr(Coeff _lb,const Expr &e) :
   1.104 +      expr(e), lb(_lb), ub(NaN) {}
   1.105 +  };
   1.106 +
   1.107 +  template<class E>
   1.108 +  const typename LinConstr<E>::Coeff LinConstr<E>::INF=
   1.109 +    std::numeric_limits<Coeff>::infinity();
   1.110 +  template<class E>
   1.111 +  const typename LinConstr<E>::Coeff LinConstr<E>::NaN=
   1.112 +    std::numeric_limits<Coeff>::quiet_NaN();
   1.113 +
   1.114 +  
   1.115 +  template<class E>
   1.116 +  typename enable_if<typename E::IsLinExpression, LinConstr<E> >::type
   1.117 +  operator<=(const E &e,const E &f) 
   1.118 +  {
   1.119 +    return LinConstr<E>(-LinConstr<E>::INF,e-f,0);
   1.120 +  }
   1.121 +
   1.122 +  template<class E>
   1.123 +  typename enable_if<typename E::IsLinExpression, LinConstr<E> >::type
   1.124 +  operator>=(const E &e,const E &f) 
   1.125 +  {
   1.126 +    return LinConstr<E>(-LinConstr<E>::INF,f-e,0);
   1.127 +  }
   1.128 +
   1.129 +  template<class E>
   1.130 +  typename enable_if<typename E::IsLinExpression, LinConstr<E> >::type
   1.131 +  operator==(const E &e,const E &f) 
   1.132 +  {
   1.133 +    return LinConstr<E>(0,e-f,0);
   1.134 +  }
   1.135 +  
   1.136 +  //////////////////////////////
   1.137 +
   1.138 +  template<class E>
   1.139 +  typename enable_if<typename E::IsLinExpression, LinConstr<E> >::type
   1.140 +  operator<=(const E &e,const typename E::Coeff &n) 
   1.141 +  {
   1.142 +    return LinConstr<E>(e,n);
   1.143 +  }
   1.144 +
   1.145 +  template<class E>
   1.146 +  typename enable_if<typename E::IsLinExpression, LinConstr<E> >::type
   1.147 +  operator>=(const E &e,const typename E::Coeff &n) 
   1.148 +  {
   1.149 +    return LinConstr<E>(n,e);
   1.150 +  }
   1.151 +
   1.152 +  template<class E>
   1.153 +  typename enable_if<typename E::IsLinExpression, LinConstr<E> >::type
   1.154 +  operator==(const E &e,const typename E::Coeff &n) 
   1.155 +  {
   1.156 +    return LinConstr<E>(n,e,n);
   1.157 +  }
   1.158 +
   1.159 +  //////////////////////////////
   1.160 +
   1.161 +  template<class E>
   1.162 +  typename enable_if<typename E::IsLinExpression, LinConstr<E> >::type
   1.163 +  operator<=(const typename E::Coeff &n,const E &e) 
   1.164 +  {
   1.165 +    return LinConstr<E>(n,e);
   1.166 +  }
   1.167 +
   1.168 +  template<class E>
   1.169 +  typename enable_if<typename E::IsLinExpression, LinConstr<E> >::type
   1.170 +  operator>=(const typename E::Coeff &n,const E &e) 
   1.171 +  {
   1.172 +    return LinConstr<E>(e,n);
   1.173 +  }
   1.174 +
   1.175 +  template<class E>
   1.176 +  typename enable_if<typename E::IsLinExpression, LinConstr<E> >::type
   1.177 +  operator==(const typename E::Coeff &n,const E &e) 
   1.178 +  {
   1.179 +    return LinConstr<E>(n,e,n);
   1.180 +  }
   1.181 +
   1.182 +  //////////////////////////////
   1.183 +
   1.184 +  template<class E>
   1.185 +  typename enable_if<typename E::IsLinExpression, LinConstr<E> >::type
   1.186 +  operator<=(const typename E::Coeff &n,const LinConstr<E> &c) 
   1.187 +  {
   1.188 +    LinConstr<E> tmp(c);
   1.189 +    if(tmp.lb!=tmp.NaN) throw LogicError();
   1.190 +    else tmp.lb=n;
   1.191 +    return tmp;
   1.192 +  }
   1.193 +
   1.194 +  template<class E>
   1.195 +  typename enable_if<typename E::IsLinExpression, LinConstr<E> >::type
   1.196 +  operator>=(const typename E::Coeff &n,const LinConstr<E> &c) 
   1.197 +  {
   1.198 +    LinConstr<E> tmp(c);
   1.199 +    if(tmp.ub!=tmp.NaN) throw LogicError();
   1.200 +    else tmp.ub=n;
   1.201 +    return tmp;
   1.202 +  }
   1.203 +
   1.204 +  template<class E>
   1.205 +  typename enable_if<typename E::IsLinExpression, LinConstr<E> >::type
   1.206 +  operator<=(const LinConstr<E> &c,const typename E::Coeff &n) 
   1.207 +  {
   1.208 +    LinConstr<E> tmp(c);
   1.209 +    if(tmp.ub!=tmp.NaN) throw LogicError();
   1.210 +    else tmp.ub=n;
   1.211 +    return tmp;
   1.212 +  }
   1.213 +
   1.214 +  template<class E>
   1.215 +  typename enable_if<typename E::IsLinExpression, LinConstr<E> >::type
   1.216 +  operator>=(const LinConstr<E> &c,const typename E::Coeff &n) 
   1.217 +  {
   1.218 +    LinConstr<E> tmp(c);
   1.219 +    if(tmp.lb!=tmp.NaN) throw LogicError();
   1.220 +    else tmp.lb=n;
   1.221 +    return tmp;
   1.222 +  }
   1.223 +
   1.224 +  
   1.225 +
   1.226  } //namespace lemon
   1.227  
   1.228  #endif //LEMON_LIN_EXPR_H

     2.1 --- a/src/work/athos/lp/lp_base.cc	Fri Mar 25 16:19:03 2005 +0000
     2.2 +++ b/src/work/athos/lp/lp_base.cc	Fri Mar 25 18:56:07 2005 +0000
     2.3 @@ -22,6 +22,8 @@
     2.4    
     2.5    const LpSolverBase::Value
     2.6    LpSolverBase::INF = std::numeric_limits<Value>::infinity();
     2.7 +  const LpSolverBase::Value
     2.8 +  LpSolverBase::NaN = std::numeric_limits<Value>::quiet_NaN();
     2.9  
    2.10  
    2.11  } //namespace lemon

     3.1 --- a/src/work/athos/lp/lp_base.h	Fri Mar 25 16:19:03 2005 +0000
     3.2 +++ b/src/work/athos/lp/lp_base.h	Fri Mar 25 18:56:07 2005 +0000
     3.3 @@ -116,6 +116,8 @@
     3.4      typedef double Value;
     3.5      ///The infinity constant
     3.6      static const Value INF;
     3.7 +    ///The not a number constant
     3.8 +    static const Value NaN;
     3.9      
    3.10      ///Refer to a column of the LP.
    3.11  
    3.12 @@ -167,6 +169,8 @@
    3.13      
    3.14      ///Linear expression
    3.15      typedef SparseLinExpr<Col> Expr;
    3.16 +    ///Linear constraint
    3.17 +    typedef LinConstr<Expr> Constr;
    3.18  
    3.19    protected:
    3.20      _FixId rows;
    3.21 @@ -318,6 +322,18 @@
    3.22        _setRowUpperBound(rows.floatingId(r.id),u-e.constComp());
    3.23      }
    3.24  
    3.25 +    ///Set a row (i.e a constaint) of the LP
    3.26 +
    3.27 +    ///\param r is the row to be modified
    3.28 +    ///\param c is a linear expression (see \ref Constr)
    3.29 +    ///\bug This is a temportary function. The interface will change to
    3.30 +    ///a better one.
    3.31 +    void setRow(Row r, const Constr &c) {
    3.32 +      Value lb= c.lb==NaN?-INF:lb;
    3.33 +      Value ub= c.ub==NaN?INF:lb;
    3.34 +      setRow(r,lb,c.expr,ub);
    3.35 +    }
    3.36 +
    3.37      ///Add a new row (i.e a new constaint) to the LP
    3.38  
    3.39      ///\param l is the lower bound (-\ref INF means no bound)
    3.40 @@ -332,6 +348,18 @@
    3.41        return r;
    3.42      }
    3.43  
    3.44 +    ///Add a new row (i.e a new constaint) to the LP
    3.45 +
    3.46 +    ///\param c is a linear expression (see \ref Constr)
    3.47 +    ///\return The created row.
    3.48 +    ///\bug This is a temportary function. The interface will change to
    3.49 +    ///a better one.
    3.50 +    Row addRow(const Constr &c) {
    3.51 +      Row r=addRow();
    3.52 +      setRow(r,c);
    3.53 +      return r;
    3.54 +    }
    3.55 +
    3.56      /// Set the lower bound of a column (i.e a variable)
    3.57  
    3.58      /// The upper bound of a variable (column) have to be given by an 

     4.1 --- a/src/work/athos/lp/lp_test.cc	Fri Mar 25 16:19:03 2005 +0000
     4.2 +++ b/src/work/athos/lp/lp_test.cc	Fri Mar 25 18:56:07 2005 +0000
     4.3 @@ -1,5 +1,6 @@
     4.4  #include"lp_solver_skeleton.h"
     4.5  #include"lp_glpk.h"
     4.6 +#include<lemon/list_graph.h>
     4.7  
     4.8  using namespace lemon;
     4.9  
    4.10 @@ -36,9 +37,52 @@
    4.11    lp.addRow(LP::INF,3.0*(x[1]+x[2]/2)-x[3],23);
    4.12    lp.addRow(LP::INF,3.0*(p1+p2*2-5*p3+12-p4/3)+2*p4-4,23);
    4.13    lp.addRow(LP::INF,3.0*(x[1]+x[2]*2-5*x[3]+12-x[4]/3)+2*x[4]-4,23);
    4.14 +
    4.15 +  lp.addRow(x[1]+x[3]<=x[5]-3);
    4.16 +  lp.addRow(-7<=x[1]+x[3]-12<=3);
    4.17  }
    4.18  
    4.19  
    4.20 +template<class G,class C>
    4.21 +double maxFlow(const G &g,const C &cap,typename G::Node s,typename G::Node t)
    4.22 +{
    4.23 +  LpGlpk lp;
    4.24 +  
    4.25 +  typedef G Graph;
    4.26 +  typedef typename G::Node Node;
    4.27 +  typedef typename G::NodeIt NodeIt;
    4.28 +  typedef typename G::Edge Edge;
    4.29 +  typedef typename G::EdgeIt EdgeIt;
    4.30 +  typedef typename G::OutEdgeIt OutEdgeIt;
    4.31 +  typedef typename G::InEdgeIt InEdgeIt;
    4.32 +  
    4.33 +  typename G::EdgeMap<LpGlpk::Col> x(g);
    4.34 +  // lp.addColSet(x);
    4.35 +  for(EdgeIt e(g);e!=INVALID;++e) x[e]=lp.addCol();
    4.36 +  
    4.37 +  for(EdgeIt e(g);e!=INVALID;++e) {
    4.38 +    lp.setColUpperBound(x[e],cap[e]);
    4.39 +    lp.setColLowerBound(x[e],0);
    4.40 +  }
    4.41 +
    4.42 +  for(NodeIt n(g);n!=INVALID;++n) if(n!=s&&n!=t) {
    4.43 +    LpGlpk::Expr ex;
    4.44 +    for(InEdgeIt  e(g,n);e!=INVALID;++e) ex+=x[e];
    4.45 +    for(OutEdgeIt e(g,n);e!=INVALID;++e) ex-=x[e];
    4.46 +    lp.addRow(0,ex,0);
    4.47 +  }
    4.48 +  {
    4.49 +    LpGlpk::Expr ex;
    4.50 +    for(InEdgeIt  e(g,t);e!=INVALID;++e) ex+=x[e];
    4.51 +    for(OutEdgeIt e(g,t);e!=INVALID;++e) ex-=x[e];
    4.52 +    lp.setObj(ex);
    4.53 +  }
    4.54 +
    4.55 +  lp.solve();
    4.56 +
    4.57 +  return 0;
    4.58 +}
    4.59 +
    4.60  int main() 
    4.61  {
    4.62    LpSolverSkeleton lp_skel;
    4.63 @@ -46,4 +90,10 @@
    4.64  
    4.65    lpTest(lp_skel);
    4.66    lpTest(lp_glpk);
    4.67 +
    4.68 +  ListGraph g;
    4.69 +  ListGraph::EdgeMap<double> cap(g);
    4.70 +  
    4.71 +  maxFlow(g,cap,ListGraph::NodeIt(g),ListGraph::NodeIt(g));
    4.72 +
    4.73  }