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Port fix for gap logic

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This commit is contained in:
Patrick Niklaus 2016-11-02 19:42:48 +00:00
parent 42afcdf115
commit 3905074a81
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GPG Key ID: E426891B5F978B1B
1 changed files with 128 additions and 122 deletions
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250
include/engine/routing_algorithms/map_matching.hpp
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@ -176,24 +176,133 @@ class MapMatching final : public BasicRoutingInterface<DataFacadeT, MapMatching<
prev_unbroken_timestamps.push_back(initial_timestamp); prev_unbroken_timestamps.push_back(initial_timestamp);
for (auto t = initial_timestamp + 1; t < candidates_list.size(); ++t) for (auto t = initial_timestamp + 1; t < candidates_list.size(); ++t)
{ {
const bool gap_in_trace = [&, use_timestamps]() {
// use temporal information if available to determine a split
if (use_timestamps)
{
return trace_timestamps[t] - trace_timestamps[prev_unbroken_timestamps.back()] >
max_broken_time;
}
else
{
return t - prev_unbroken_timestamps.back() > MAX_BROKEN_STATES;
}
}();
if (!gap_in_trace)
{
BOOST_ASSERT(!prev_unbroken_timestamps.empty());
const std::size_t prev_unbroken_timestamp = prev_unbroken_timestamps.back();
const auto &prev_viterbi = model.viterbi[prev_unbroken_timestamp];
const auto &prev_pruned = model.pruned[prev_unbroken_timestamp];
const auto &prev_unbroken_timestamps_list =
candidates_list[prev_unbroken_timestamp];
const auto &prev_coordinate = trace_coordinates[prev_unbroken_timestamp];
auto &current_viterbi = model.viterbi[t];
auto &current_pruned = model.pruned[t];
auto &current_parents = model.parents[t];
auto &current_lengths = model.path_distances[t];
const auto &current_timestamps_list = candidates_list[t];
const auto &current_coordinate = trace_coordinates[t];
const auto haversine_distance = util::coordinate_calculation::haversineDistance(
prev_coordinate, current_coordinate);
// assumes minumum of 0.1 m/s
const int duration_upper_bound =
((haversine_distance + max_distance_delta) * 0.25) * 10;
// compute d_t for this timestamp and the next one
for (const auto s : util::irange<std::size_t>(0UL, prev_viterbi.size()))
{
if (prev_pruned[s])
{
continue;
}
for (const auto s_prime :
util::irange<std::size_t>(0UL, current_viterbi.size()))
{
const double emission_pr = emission_log_probabilities[t][s_prime];
double new_value = prev_viterbi[s] + emission_pr;
if (current_viterbi[s_prime] > new_value)
{
continue;
}
forward_heap.Clear();
reverse_heap.Clear();
double network_distance;
if (super::facade->GetCoreSize() > 0)
{
forward_core_heap.Clear();
reverse_core_heap.Clear();
network_distance = super::GetNetworkDistanceWithCore(
forward_heap,
reverse_heap,
forward_core_heap,
reverse_core_heap,
prev_unbroken_timestamps_list[s].phantom_node,
current_timestamps_list[s_prime].phantom_node,
duration_upper_bound);
}
else
{
network_distance = super::GetNetworkDistance(
forward_heap,
reverse_heap,
prev_unbroken_timestamps_list[s].phantom_node,
current_timestamps_list[s_prime].phantom_node);
}
// get distance diff between loc1/2 and locs/s_prime
const auto d_t = std::abs(network_distance - haversine_distance);
// very low probability transition -> prune
if (d_t >= max_distance_delta)
{
continue;
}
const double transition_pr = transition_log_probability(d_t);
new_value += transition_pr;
if (new_value > current_viterbi[s_prime])
{
current_viterbi[s_prime] = new_value;
current_parents[s_prime] = std::make_pair(prev_unbroken_timestamp, s);
current_lengths[s_prime] = network_distance;
current_pruned[s_prime] = false;
model.breakage[t] = false;
}
}
}
if (model.breakage[t])
{
// save start of breakage -> we need this as split point
if (t < breakage_begin)
{
breakage_begin = t;
}
BOOST_ASSERT(prev_unbroken_timestamps.size() > 0);
// remove both ends of the breakage
prev_unbroken_timestamps.pop_back();
}
else
{
prev_unbroken_timestamps.push_back(t);
}
}
// breakage recover has removed all previous good points // breakage recover has removed all previous good points
bool trace_split = prev_unbroken_timestamps.empty(); const bool trace_split = prev_unbroken_timestamps.empty();
// use temporal information if available to determine a split if (trace_split || gap_in_trace)
if (use_timestamps)
{
trace_split =
trace_split ||
(trace_timestamps[t] - trace_timestamps[prev_unbroken_timestamps.back()] >
max_broken_time);
}
else
{
trace_split =
trace_split || (t - prev_unbroken_timestamps.back() > MAX_BROKEN_STATES);
}
if (trace_split)
{ {
std::size_t split_index = t; std::size_t split_index = t;
if (breakage_begin != map_matching::INVALID_STATE) if (breakage_begin != map_matching::INVALID_STATE)
@ -217,112 +326,9 @@ class MapMatching final : public BasicRoutingInterface<DataFacadeT, MapMatching<
// Important: We potentially go back here! // Important: We potentially go back here!
// However since t > new_start >= breakge_begin // However since t > new_start >= breakge_begin
// we can only reset trace_coordindates.size() times. // we can only reset trace_coordindates.size() times.
t = new_start + 1; t = new_start;
} // note: the head of the loop will call ++t, hence the next
// iteration will actually be on new_start+1
BOOST_ASSERT(!prev_unbroken_timestamps.empty());
const std::size_t prev_unbroken_timestamp = prev_unbroken_timestamps.back();
const auto &prev_viterbi = model.viterbi[prev_unbroken_timestamp];
const auto &prev_pruned = model.pruned[prev_unbroken_timestamp];
const auto &prev_unbroken_timestamps_list = candidates_list[prev_unbroken_timestamp];
const auto &prev_coordinate = trace_coordinates[prev_unbroken_timestamp];
auto &current_viterbi = model.viterbi[t];
auto &current_pruned = model.pruned[t];
auto &current_parents = model.parents[t];
auto &current_lengths = model.path_distances[t];
const auto &current_timestamps_list = candidates_list[t];
const auto &current_coordinate = trace_coordinates[t];
const auto haversine_distance = util::coordinate_calculation::haversineDistance(
prev_coordinate, current_coordinate);
// assumes minumum of 0.1 m/s
const int duration_uppder_bound =
((haversine_distance + max_distance_delta) * 0.25) * 10;
// compute d_t for this timestamp and the next one
for (const auto s : util::irange<std::size_t>(0UL, prev_viterbi.size()))
{
if (prev_pruned[s])
{
continue;
}
for (const auto s_prime : util::irange<std::size_t>(0UL, current_viterbi.size()))
{
const double emission_pr = emission_log_probabilities[t][s_prime];
double new_value = prev_viterbi[s] + emission_pr;
if (current_viterbi[s_prime] > new_value)
{
continue;
}
forward_heap.Clear();
reverse_heap.Clear();
double network_distance;
if (super::facade->GetCoreSize() > 0)
{
forward_core_heap.Clear();
reverse_core_heap.Clear();
network_distance = super::GetNetworkDistanceWithCore(
forward_heap,
reverse_heap,
forward_core_heap,
reverse_core_heap,
prev_unbroken_timestamps_list[s].phantom_node,
current_timestamps_list[s_prime].phantom_node,
duration_uppder_bound);
}
else
{
network_distance = super::GetNetworkDistance(
forward_heap,
reverse_heap,
prev_unbroken_timestamps_list[s].phantom_node,
current_timestamps_list[s_prime].phantom_node);
}
// get distance diff between loc1/2 and locs/s_prime
const auto d_t = std::abs(network_distance - haversine_distance);
// very low probability transition -> prune
if (d_t >= max_distance_delta)
{
continue;
}
const double transition_pr = transition_log_probability(d_t);
new_value += transition_pr;
if (new_value > current_viterbi[s_prime])
{
current_viterbi[s_prime] = new_value;
current_parents[s_prime] = std::make_pair(prev_unbroken_timestamp, s);
current_lengths[s_prime] = network_distance;
current_pruned[s_prime] = false;
model.breakage[t] = false;
}
}
}
if (model.breakage[t])
{
// save start of breakage -> we need this as split point
if (t < breakage_begin)
{
breakage_begin = t;
}
BOOST_ASSERT(prev_unbroken_timestamps.size() > 0);
// remove both ends of the breakage
prev_unbroken_timestamps.pop_back();
}
else
{
prev_unbroken_timestamps.push_back(t);
} }
} }