Major improvements in NetworkSimplex.
Main changes:
- Use -potenital[] instead of potential[] to conform to the usual
terminology.
- Use function parameter instead of #define commands to select pivot rule.
- Use much faster implementation for the candidate list pivot rule.
It is about 5-20 times faster now.
- Add a new pivot rule called "Limited Search" that is a modified
version of "Block Search". It is about 25 percent faster on rather
sparse graphs.
- By default "Limited Search" is used for sparse graphs and
"Block Search" is used otherwise. This combined method is the most
efficient on every input class.
- Change the name of private members to start with "_".
- Change the name of function parameters not to start with "_".
- Remove unnecessary documentation for private members.
- Many doc improvements.
3 * This file is a part of LEMON, a generic C++ optimization library
5 * Copyright (C) 2003-2008
6 * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
7 * (Egervary Research Group on Combinatorial Optimization, EGRES).
9 * Permission to use, modify and distribute this software is granted
10 * provided that this copyright notice appears in all copies. For
11 * precise terms see the accompanying LICENSE file.
13 * This software is provided "AS IS" with no warranty of any kind,
14 * express or implied, and with no claim as to its suitability for any
21 ///\brief Demonstrating the usage of LEMON's General Flow algorithm
23 /// This demo program reads a general network circulation problem from the
24 /// file 'circulation-input.lgf', runs the preflow based algorithm for
25 /// finding a feasible solution and writes the output
26 /// to 'circulation-input.lgf'
28 /// \include circulation_demo.cc
32 #include <lemon/list_graph.h>
33 #include <lemon/circulation.h>
34 #include <lemon/graph_reader.h>
35 #include <lemon/graph_writer.h>
37 using namespace lemon;
40 int main (int, char*[])
43 typedef ListGraph Graph;
44 typedef Graph::Node Node;
45 typedef Graph::NodeIt NodeIt;
46 typedef Graph::Edge Edge;
47 typedef Graph::EdgeIt EdgeIt;
48 typedef Graph::EdgeMap<int> EdgeMap;
49 typedef Graph::NodeMap<int> NodeMap;
50 typedef Graph::NodeMap<double> DNodeMap;
61 GraphReader<Graph>("circulation-input.lgf", g).
62 readEdgeMap("lo_cap", lo).
63 readEdgeMap("up_cap", up).
64 readNodeMap("delta", delta).
65 readEdgeMap("label", eid).
66 readNodeMap("label", nid).
67 readNodeMap("coordinates_x", cx).
68 readNodeMap("coordinates_y", cy).
71 Circulation<Graph> gen(g,lo,up,delta);
75 std::cout << "\nA feasible flow has been found.\n";
76 if(!gen.checkFlow()) std::cerr << "Oops!!!\n";
77 GraphWriter<Graph>("circulation-output.lgf", g).
78 writeEdgeMap("lo_cap", lo).
79 writeEdgeMap("up_cap", up).
80 writeEdgeMap("flow", gen.flowMap()).
81 writeNodeMap("delta", delta).
82 writeEdgeMap("label", eid).
83 writeNodeMap("label", nid).
84 writeNodeMap("coordinates_x", cx).
85 writeNodeMap("coordinates_y", cy).
89 std::cout << "\nThere is no such a flow\n";
90 Graph::NodeMap<int> bar(g);
92 if(!gen.checkBarrier()) std::cerr << "Dual Oops!!!\n";
94 GraphWriter<Graph>("circulation-output.lgf", g).
95 writeEdgeMap("lo_cap", lo).
96 writeEdgeMap("up_cap", up).
97 writeNodeMap("barrier", bar).
98 writeNodeMap("delta", delta).
99 writeEdgeMap("label", eid).
100 writeNodeMap("label", nid).
101 writeNodeMap("coordinates_x", cx).
102 writeNodeMap("coordinates_y", cy).
105 std::cout << "The output is written to file 'circulation-output.lgf'\n\n";