lemon-0.x: src/work/marci/lp/min_cost_gen

     1 // -*- c++ -*-

     2 #ifndef LEMON_MIN_COST_GEN_FLOW_H

     3 #define LEMON_MIN_COST_GEN_FLOW_H

     4 //#include <iostream>

     5 //#include <fstream>

     7 //#include <lemon/smart_graph.h>

     8 //#include <lemon/list_graph.h>

     9 //#include <lemon/dimacs.h>

    10 //#include <lemon/time_measure.h>

    11 //#include <graph_wrapper.h>

    12 //#include <lemon/preflow.h>

    13 //#include <augmenting_flow.h>

    14 //#include <preflow_res.h>

    15 #include <lemon/../work/marci/lp/lp_solver_wrapper.h>

    17 namespace lemon {

    19   template<typename Edge, typename EdgeIndexMap>

    20   class PrimalMap {

    21   protected:

    22     LPSolverWrapper* lp;

    23     EdgeIndexMap* edge_index_map;

    24   public:

    25     PrimalMap(LPSolverWrapper& _lp, EdgeIndexMap& _edge_index_map) :

    26       lp(&_lp), edge_index_map(&_edge_index_map) { }

    27     double operator[](Edge e) const {

    28       return lp->getPrimal((*edge_index_map)[e]);

    29     }

    30   };

    32   // excess: rho-delta

    33   template <typename Graph, typename Num,

    34 	    typename Excess=typename Graph::template NodeMap<Num>,

    35 	    typename LCapMap=typename Graph::template EdgeMap<Num>,

    36 	    typename CapMap=typename Graph::template EdgeMap<Num>,

    37             typename FlowMap=typename Graph::template EdgeMap<Num>,

    38 	    typename CostMap=typename Graph::template EdgeMap<Num> >

    39   class MinCostGenFlow {

    40   protected:

    41     const Graph& g;

    42     const Excess& excess;

    43     const LCapMap& lcapacity;

    44     const CapMap& capacity;

    45     FlowMap& flow;

    46     const CostMap& cost;

    47   public:

    48     MinCostGenFlow(const Graph& _g, const Excess& _excess,

    49 		   const LCapMap& _lcapacity, const CapMap& _capacity,

    50 		   FlowMap& _flow,

    51 		   const CostMap& _cost) :

    52       g(_g), excess(_excess), lcapacity(_lcapacity),

    53       capacity(_capacity), flow(_flow), cost(_cost) { }

    54     void run() {

    55       LPSolverWrapper lp;

    56       lp.setMinimize();

    57       typedef LPSolverWrapper::ColIt ColIt;

    58       typedef LPSolverWrapper::RowIt RowIt;

    59       typedef typename Graph::template EdgeMap<ColIt> EdgeIndexMap;

    60       EdgeIndexMap edge_index_map(g);

    61       PrimalMap<typename Graph::Edge, EdgeIndexMap> lp_flow(lp, edge_index_map);

    62       for (typename Graph::EdgeIt e(g); e!=INVALID; ++e) {

    63 	ColIt col_it=lp.addCol();

    64 	edge_index_map.set(e, col_it);

    65 	if (lcapacity[e]==capacity[e])

    66 	  lp.setColBounds(col_it, LPX_FX, lcapacity[e], capacity[e]);

    67 	else

    68 	  lp.setColBounds(col_it, LPX_DB, lcapacity[e], capacity[e]);

    69 	lp.setObjCoef(col_it, cost[e]);

    70       }

    71       for (typename Graph::NodeIt n(g); n!=INVALID; ++n) {

    72 	typename Graph::template EdgeMap<Num> coeffs(g, 0);

    73 	for (typename Graph::InEdgeIt e(g, n); e!=INVALID; ++e)

    74 	coeffs.set(e, coeffs[e]+1);

    75 	for (typename Graph::OutEdgeIt e(g, n); e!=INVALID; ++e)

    76 	coeffs.set(e, coeffs[e]-1);

    77 	RowIt row_it=lp.addRow();

    78 	typename std::vector< std::pair<ColIt, double> > row;

    79 	//std::cout << "node:" <<g.id(n)<<std::endl;

    80 	for (typename Graph::EdgeIt e(g); e!=INVALID; ++e) {

    81 	  if (coeffs[e]!=0) {

    82 	    //std::cout << " edge:" <<g.id(e)<<" "<<coeffs[e];

    83 	    row.push_back(std::make_pair(edge_index_map[e], coeffs[e]));

    84 	  }

    85 	}

    86 	//std::cout << std::endl;

    87 	lp.setRowCoeffs(row_it, row.begin(), row.end());

    88 	lp.setRowBounds(row_it, LPX_FX, 0.0, 0.0);

    89       }

    90       lp.solveSimplex();

    91       //std::cout << lp.colNum() << std::endl;

    92       //std::cout << lp.rowNum() << std::endl;

    93       //std::cout << "flow value: "<< lp.getObjVal() << std::endl;

    94       for (typename Graph::EdgeIt e(g); e!=INVALID; ++e)

    95       flow.set(e, lp_flow[e]);

    96     }

    97   };

    99 } // namespace lemon

   101 #endif //LEMON_MIN_COST_GEN_FLOW_H

author	marci
	Mon, 22 Nov 2004 09:12:33 +0000
changeset 1017	f588efc6d607
child 1025	3b1ad8bc21da
permissions	-rw-r--r--