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Split traces into subtraces

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This commit is contained in:
Patrick Niklaus
2015-02-17 12:22:11 +01:00
parent d620da365e
commit cb4a81008c
2 changed files with 155 additions and 98 deletions
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routing_algorithms/map_matching.hpp
+73 -33
View File
@@ -70,9 +70,19 @@ JSON::Array makeJSONArray(Args... args)
namespace Matching
{
typedef std::vector<std::pair<PhantomNode, double>> CandidateList;
typedef std::vector<CandidateList> CandidateLists;
typedef std::pair<PhantomNodes, double> PhantomNodesWithProbability;
struct SubMatching
{
std::vector<PhantomNode> nodes;
unsigned begin_idx;
unsigned end_idx;
double length;
double confidence;
};
using CandidateList = std::vector<std::pair<PhantomNode, double>>;
using CandidateLists = std::vector<CandidateList>;
using SubMatchingList = std::vector<SubMatching>;
constexpr static const unsigned max_number_of_candidates = 20;
}
@@ -313,8 +323,7 @@ template <class DataFacadeT> class MapMatching final
void operator()(const Matching::CandidateLists &timestamp_list,
const std::vector<FixedPointCoordinate> coordinate_list,
std::vector<PhantomNode>& matched_nodes,
float& matched_length,
Matching::SubMatchingList& sub_matchings,
JSON::Object& _debug_info) const
{
BOOST_ASSERT(timestamp_list.size() > 0);
@@ -348,6 +357,7 @@ template <class DataFacadeT> class MapMatching final
_debug_states.values.push_back(_debug_timestamps);
}
std::vector<unsigned> split_points;
std::vector<unsigned> prev_unbroken_timestamps;
prev_unbroken_timestamps.reserve(timestamp_list.size());
prev_unbroken_timestamps.push_back(initial_timestamp);
@@ -366,6 +376,8 @@ template <class DataFacadeT> class MapMatching final
const auto& current_timestamps_list = timestamp_list[t];
const auto& current_coordinate = coordinate_list[t];
std::cout << " # " << prev_unbroken_timestamp << " -> " << t << std::endl;
// compute d_t for this timestamp and the next one
for (auto s = 0u; s < prev_viterbi.size(); ++s)
{
@@ -433,16 +445,24 @@ template <class DataFacadeT> class MapMatching final
if (model.breakage[t])
{
std::cout << "Broken!" << std::endl;
// TODO we actually don't need to go to the beginning.
// with temporal information we can split after _n_
// skipped states
if (prev_unbroken_timestamps.size() > 1)
{
// remove both ends of the breakge
prev_unbroken_timestamps.pop_back();
}
// we reached the beginning of the trace, discard the whole beginning
// we reached the beginning of the trace and it is still broken
// -> split the trace here
else
{
split_points.push_back(t);
// note this preserves everything before t
model.clear(t);
model.initialize(t);
prev_unbroken_timestamps.push_back(t);
}
}
else
@@ -451,41 +471,61 @@ template <class DataFacadeT> class MapMatching final
}
}
if (prev_unbroken_timestamps.size() < 1)
if (prev_unbroken_timestamps.size() > 1)
{
return;
split_points.push_back(prev_unbroken_timestamps.back()+1);
}
unsigned last_unbroken_timestamp = prev_unbroken_timestamps.back();
// loop through the columns, and only compare the last entry
auto max_element_iter = std::max_element(model.viterbi[last_unbroken_timestamp].begin(),
model.viterbi[last_unbroken_timestamp].end());
auto parent_index = std::distance(model.viterbi[last_unbroken_timestamp].begin(), max_element_iter);
std::deque<std::pair<std::size_t, std::size_t>> reconstructed_indices;
for (auto i = last_unbroken_timestamp; i > initial_timestamp; --i)
unsigned sub_matching_begin = initial_timestamp;
for (const unsigned sub_matching_end : split_points)
{
if (model.breakage[i])
Matching::SubMatching matching;
// matchings that only consist of one candidate are invalid
if (sub_matching_end - sub_matching_begin < 2)
{
sub_matching_begin = sub_matching_end;
continue;
reconstructed_indices.emplace_front(i, parent_index);
parent_index = model.parents[i][parent_index];
}
reconstructed_indices.emplace_front(initial_timestamp, parent_index);
}
matched_length = 0.0f;
matched_nodes.resize(reconstructed_indices.size());
for (auto i = 0u; i < reconstructed_indices.size(); ++i)
{
auto timestamp_index = reconstructed_indices[i].first;
auto location_index = reconstructed_indices[i].second;
std::cout << sub_matching_begin << " -> " << sub_matching_end << std::endl;
matched_nodes[i] = timestamp_list[timestamp_index][location_index].first;
matched_length += model.path_lengths[timestamp_index][location_index];
matching.begin_idx = sub_matching_begin;
matching.end_idx = sub_matching_end;
_debug_states.values[timestamp_index]
.get<JSONVariantArray>().get().values[location_index]
.get<JSONVariantObject>().get().values["chosen"] = true;
// loop through the columns, and only compare the last entry
auto max_element_iter = std::max_element(model.viterbi[sub_matching_end-1].begin(),
model.viterbi[sub_matching_end-1].end());
auto parent_index = std::distance(model.viterbi[sub_matching_end-1].begin(), max_element_iter);
std::deque<std::pair<std::size_t, std::size_t>> reconstructed_indices;
for (auto i = sub_matching_end-1; i > sub_matching_begin; --i)
{
if (model.breakage[i])
continue;
reconstructed_indices.emplace_front(i, parent_index);
parent_index = model.parents[i][parent_index];
}
reconstructed_indices.emplace_front(initial_timestamp, parent_index);
matching.length = 0.0f;
matching.nodes.resize(reconstructed_indices.size());
for (auto i = 0u; i < reconstructed_indices.size(); ++i)
{
auto timestamp_index = reconstructed_indices[i].first;
auto location_index = reconstructed_indices[i].second;
matching.nodes[i] = timestamp_list[timestamp_index][location_index].first;
matching.length += model.path_lengths[timestamp_index][location_index];
_debug_states.values[timestamp_index]
.get<JSONVariantArray>().get().values[location_index]
.get<JSONVariantObject>().get().values["chosen"] = true;
}
sub_matchings.push_back(matching);
sub_matching_begin = sub_matching_end;
}
JSON::Array _debug_breakage;