Location: LEMON/LEMON-official/test/min_cost_arborescence_test.cc

Load file history
gravatar
kpeter (Peter Kovacs)
Implement the scaling Price Refinement heuristic in CostScaling (#417) instead of Early Termination. These two heuristics are similar, but the newer one is faster and not only makes it possible to skip some epsilon phases, but it can improve the performance of the other phases, as well.
/* -*- mode: C++; indent-tabs-mode: nil; -*-
*
* This file is a part of LEMON, a generic C++ optimization library.
*
* Copyright (C) 2003-2010
* Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
* (Egervary Research Group on Combinatorial Optimization, 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 <iostream>
#include <set>
#include <vector>
#include <iterator>
#include <lemon/smart_graph.h>
#include <lemon/min_cost_arborescence.h>
#include <lemon/lgf_reader.h>
#include <lemon/concepts/digraph.h>
#include "test_tools.h"
using namespace lemon;
using namespace std;
const char test_lgf[] =
"@nodes\n"
"label\n"
"0\n"
"1\n"
"2\n"
"3\n"
"4\n"
"5\n"
"6\n"
"7\n"
"8\n"
"9\n"
"@arcs\n"
" label cost\n"
"1 8 0 107\n"
"0 3 1 70\n"
"2 1 2 46\n"
"4 1 3 28\n"
"4 4 4 91\n"
"3 9 5 76\n"
"9 8 6 61\n"
"8 1 7 39\n"
"9 8 8 74\n"
"8 0 9 39\n"
"4 3 10 45\n"
"2 2 11 34\n"
"0 1 12 100\n"
"6 3 13 95\n"
"4 1 14 22\n"
"1 1 15 31\n"
"7 2 16 51\n"
"2 6 17 29\n"
"8 3 18 115\n"
"6 9 19 32\n"
"1 1 20 60\n"
"0 3 21 40\n"
"@attributes\n"
"source 0\n";
void checkMinCostArborescenceCompile()
{
typedef double VType;
typedef concepts::Digraph Digraph;
typedef concepts::ReadMap<Digraph::Arc, VType> CostMap;
typedef Digraph::Node Node;
typedef Digraph::Arc Arc;
typedef concepts::WriteMap<Digraph::Arc, bool> ArbMap;
typedef concepts::ReadWriteMap<Digraph::Node, Digraph::Arc> PredMap;
typedef MinCostArborescence<Digraph, CostMap>::
SetArborescenceMap<ArbMap>::
SetPredMap<PredMap>::Create MinCostArbType;
Digraph g;
Node s, n;
Arc e;
VType c;
bool b;
int i;
CostMap cost;
ArbMap arb;
PredMap pred;
MinCostArbType mcarb_test(g, cost);
const MinCostArbType& const_mcarb_test = mcarb_test;
mcarb_test
.arborescenceMap(arb)
.predMap(pred)
.run(s);
mcarb_test.init();
mcarb_test.addSource(s);
mcarb_test.start();
n = mcarb_test.processNextNode();
b = const_mcarb_test.emptyQueue();
i = const_mcarb_test.queueSize();
c = const_mcarb_test.arborescenceCost();
b = const_mcarb_test.arborescence(e);
e = const_mcarb_test.pred(n);
const MinCostArbType::ArborescenceMap &am =
const_mcarb_test.arborescenceMap();
const MinCostArbType::PredMap &pm =
const_mcarb_test.predMap();
b = const_mcarb_test.reached(n);
b = const_mcarb_test.processed(n);
i = const_mcarb_test.dualNum();
c = const_mcarb_test.dualValue();
i = const_mcarb_test.dualSize(i);
c = const_mcarb_test.dualValue(i);
ignore_unused_variable_warning(am);
ignore_unused_variable_warning(pm);
}
int main() {
typedef SmartDigraph Digraph;
DIGRAPH_TYPEDEFS(Digraph);
typedef Digraph::ArcMap<double> CostMap;
Digraph digraph;
CostMap cost(digraph);
Node source;
std::istringstream is(test_lgf);
digraphReader(digraph, is).
arcMap("cost", cost).
node("source", source).run();
MinCostArborescence<Digraph, CostMap> mca(digraph, cost);
mca.run(source);
vector<pair<double, set<Node> > > dualSolution(mca.dualNum());
for (int i = 0; i < mca.dualNum(); ++i) {
dualSolution[i].first = mca.dualValue(i);
for (MinCostArborescence<Digraph, CostMap>::DualIt it(mca, i);
it != INVALID; ++it) {
dualSolution[i].second.insert(it);
}
}
for (ArcIt it(digraph); it != INVALID; ++it) {
if (mca.reached(digraph.source(it))) {
double sum = 0.0;
for (int i = 0; i < int(dualSolution.size()); ++i) {
if (dualSolution[i].second.find(digraph.target(it))
!= dualSolution[i].second.end() &&
dualSolution[i].second.find(digraph.source(it))
== dualSolution[i].second.end()) {
sum += dualSolution[i].first;
}
}
if (mca.arborescence(it)) {
check(sum == cost[it], "Invalid dual solution");
}
check(sum <= cost[it], "Invalid dual solution");
}
}
check(mca.dualValue() == mca.arborescenceCost(), "Invalid dual solution");
check(mca.reached(source), "Invalid arborescence");
for (ArcIt a(digraph); a != INVALID; ++a) {
check(!mca.reached(digraph.source(a)) ||
mca.reached(digraph.target(a)), "Invalid arborescence");
}
for (NodeIt n(digraph); n != INVALID; ++n) {
if (!mca.reached(n)) continue;
int cnt = 0;
for (InArcIt a(digraph, n); a != INVALID; ++a) {
if (mca.arborescence(a)) {
check(mca.pred(n) == a, "Invalid arborescence");
++cnt;
}
}
check((n == source ? cnt == 0 : cnt == 1), "Invalid arborescence");
}
Digraph::ArcMap<bool> arborescence(digraph);
check(mca.arborescenceCost() ==
minCostArborescence(digraph, cost, source, arborescence),
"Wrong result of the function interface");
return 0;
}