r937:1226290a9b7d
Tue, 15 Mar 2011 19:52:31
[Not Reviewed]
0 comments (0 inline)
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| ... | ... |
@@ -238,5 +238,4 @@ |
| 238 | 238 |
}; |
| 239 | 239 |
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typedef StaticVectorMap<StaticDigraph::Node, LargeCost> LargeCostNodeMap; |
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| 241 | 240 |
typedef StaticVectorMap<StaticDigraph::Arc, LargeCost> LargeCostArcMap; |
| 242 | 241 |
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@@ -289,12 +288,4 @@ |
| 289 | 288 |
int _max_rank; |
| 290 | 289 |
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// Data for a StaticDigraph structure |
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typedef std::pair<int, int> IntPair; |
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StaticDigraph _sgr; |
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std::vector<IntPair> _arc_vec; |
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std::vector<LargeCost> _cost_vec; |
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LargeCostArcMap _cost_map; |
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LargeCostNodeMap _pi_map; |
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public: |
| 300 | 291 |
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| ... | ... |
@@ -343,5 +334,4 @@ |
| 343 | 334 |
CostScaling(const GR& graph) : |
| 344 | 335 |
_graph(graph), _node_id(graph), _arc_idf(graph), _arc_idb(graph), |
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_cost_map(_cost_vec), _pi_map(_pi), |
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| 346 | 336 |
INF(std::numeric_limits<Value>::has_infinity ? |
| 347 | 337 |
std::numeric_limits<Value>::infinity() : |
| ... | ... |
@@ -620,7 +610,4 @@ |
| 620 | 610 |
_next_out.resize(_res_node_num); |
| 621 | 611 |
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_arc_vec.reserve(_res_arc_num); |
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_cost_vec.reserve(_res_arc_num); |
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// Copy the graph |
| 626 | 613 |
int i = 0, j = 0, k = 2 * _arc_num + _node_num; |
| ... | ... |
@@ -924,21 +911,62 @@ |
| 924 | 911 |
} |
| 925 | 912 |
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// Compute node potentials for the original costs |
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_arc_vec.clear(); |
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// Compute node potentials (dual solution) |
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for (int i = 0; i != _res_node_num; ++i) {
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_pi[i] = static_cast<Cost>(_pi[i] / (_res_node_num * _alpha)); |
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} |
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bool optimal = true; |
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for (int i = 0; optimal && i != _res_node_num; ++i) {
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LargeCost pi_i = _pi[i]; |
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int last_out = _first_out[i+1]; |
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for (int j = _first_out[i]; j != last_out; ++j) {
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if (_res_cap[j] > 0 && _scost[j] + pi_i - _pi[_target[j]] < 0) {
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optimal = false; |
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break; |
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} |
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} |
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} |
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if (!optimal) {
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// Compute node potentials for the original costs with BellmanFord |
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// (if it is necessary) |
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typedef std::pair<int, int> IntPair; |
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StaticDigraph sgr; |
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std::vector<IntPair> arc_vec; |
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std::vector<LargeCost> cost_vec; |
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LargeCostArcMap cost_map(cost_vec); |
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arc_vec.clear(); |
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cost_vec.clear(); |
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| 929 | 940 |
for (int j = 0; j != _res_arc_num; ++j) {
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| 930 | 941 |
if (_res_cap[j] > 0) {
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_arc_vec.push_back(IntPair(_source[j], _target[j])); |
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_cost_vec.push_back(_scost[j]); |
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int u = _source[j], v = _target[j]; |
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arc_vec.push_back(IntPair(u, v)); |
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cost_vec.push_back(_scost[j] + _pi[u] - _pi[v]); |
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} |
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} |
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sgr.build(_res_node_num, arc_vec.begin(), arc_vec.end()); |
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| 936 | 948 |
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typename BellmanFord<StaticDigraph, LargeCostArcMap> |
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::template SetDistMap<LargeCostNodeMap>::Create bf(_sgr, _cost_map); |
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typename BellmanFord<StaticDigraph, LargeCostArcMap>::Create |
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bf(sgr, cost_map); |
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bf.init(0); |
| 941 | 952 |
bf.start(); |
| 942 | 953 |
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for (int i = 0; i != _res_node_num; ++i) {
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_pi[i] += bf.dist(sgr.node(i)); |
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} |
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} |
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// Shift potentials to meet the requirements of the GEQ type |
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// optimality conditions |
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LargeCost max_pot = _pi[_root]; |
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for (int i = 0; i != _res_node_num; ++i) {
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if (_pi[i] > max_pot) max_pot = _pi[i]; |
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} |
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if (max_pot != 0) {
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for (int i = 0; i != _res_node_num; ++i) {
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_pi[i] -= max_pot; |
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} |
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} |
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| 943 | 971 |
// Handle non-zero lower bounds |
| 944 | 972 |
if (_have_lower) {
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