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Parameter tuning for different route lengths

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Patrick Niklaus 2018-04-22 16:34:31 +00:00 committed by Patrick Niklaus
parent 61101db8cf
commit 77a740c0fb
1 changed files with 12 additions and 9 deletions
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21
src/engine/routing_algorithms/alternative_path_mld.cpp
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@ -47,13 +47,13 @@ struct Parameters
double kAtMostLongerBy = 0.25;
// Alternative paths similarity requirement (sharing).
// At least 15% different than the shortest path.
double kAtLeastDifferentBy = 0.85;
double kAtMostSameBy = 0.85;
// Alternative paths are still reasonable around the via node candidate (local optimality).
// At least optimal around 10% sub-paths around the via node candidate.
double kAtLeastOptimalAroundViaBy = 0.1;
// Alternative paths similarity requirement (sharing) based on calles.
// At least 15% different than the shortest path.
double kCellsAtLeastDifferentBy = 0.85;
double kCellsAtMostSameBy = 0.85;
};
// Represents a via middle node where forward (from s) and backward (from t)
@ -140,27 +140,30 @@ Parameters parametersFromRequest(const PhantomNodes &phantom_node_pair)
if (distance < 10000.)
{
parameters.kAlternativesToUnpackFactor = 10.0;
parameters.kCellsAtLeastDifferentBy = 1.0;
parameters.kCellsAtMostSameBy = 1.0;
parameters.kAtLeastOptimalAroundViaBy = 0.2;
parameters.kAtMostSameBy = 0.50;
}
// 20km
else if (distance < 20000.)
{
parameters.kAlternativesToUnpackFactor = 8.0;
parameters.kCellsAtLeastDifferentBy = 1.0;
parameters.kCellsAtMostSameBy = 1.0;
parameters.kAtLeastOptimalAroundViaBy = 0.2;
parameters.kAtMostSameBy = 0.60;
}
// 50km
else if (distance < 50000.)
{
parameters.kAlternativesToUnpackFactor = 6.0;
parameters.kCellsAtLeastDifferentBy = 0.95;
parameters.kCellsAtMostSameBy = 0.95;
parameters.kAtMostSameBy = 0.70;
}
// 100km
else if (distance < 100000.)
{
parameters.kAlternativesToUnpackFactor = 4.0;
parameters.kCellsAtLeastDifferentBy = 0.75;
parameters.kCellsAtMostSameBy = 0.75;
}
return parameters;
@ -256,7 +259,7 @@ RandIt filterPackedPathsByCellSharing(RandIt first,
const Parameters &parameters)
{
// In this case we don't need to calculate sharing, because it would not filter anything
if (parameters.kCellsAtLeastDifferentBy >= 1.0)
if (parameters.kCellsAtMostSameBy >= 1.0)
return last;
util::static_assert_iter_category<RandIt, std::random_access_iterator_tag>();
@ -311,7 +314,7 @@ RandIt filterPackedPathsByCellSharing(RandIt first,
const auto sharing = 1. - difference;
if (sharing > parameters.kCellsAtLeastDifferentBy)
if (sharing > parameters.kCellsAtMostSameBy)
{
return true;
}
@ -491,7 +494,7 @@ RandIt filterUnpackedPathsBySharing(RandIt first,
BOOST_ASSERT(sharing >= 0.);
BOOST_ASSERT(sharing <= 1.);
if (sharing > parameters.kAtLeastDifferentBy)
if (sharing > parameters.kAtMostSameBy)
{
return true;
}