Module path 

Train path calculation module

This module provides probabilistic train path calculation through rail networks using GNSS data and network topology (netrelations).

Overview

The path calculation algorithm:

1. Identifies candidate netelements for each GNSS position
2. Calculates probabilities based on distance and heading alignment
3. Constructs paths bidirectionally (forward and backward)
4. Validates path continuity and navigability
5. Selects the highest probability path

Examples

use tp_lib_core::{calculate_train_path, PathConfig, GnssPosition, Netelement, NetRelation};

let gnss_positions: Vec<GnssPosition> = vec![]; // Load GNSS data
let netelements: Vec<Netelement> = vec![]; // Load network
let netrelations: Vec<NetRelation> = vec![]; // Load topology
let config = PathConfig::default();

let result = calculate_train_path(
    &gnss_positions,
    &netelements,
    &netrelations,
    &config,
)?;

if result.path.is_some() {
    println!("Path calculated successfully");
}

Re-exports

pub use debug::export_all_debug_info;

pub use debug::export_gap_fills;

pub use debug::export_hmm_candidate_netelements;

pub use debug::export_hmm_emission_probabilities;

pub use debug::export_hmm_selected_path;

pub use debug::export_hmm_viterbi_trace;

pub use debug::export_path_sanity_decisions;

pub use graph::build_topology_graph;

pub use graph::cached_shortest_path_distance;

pub use graph::shortest_path_distance;

pub use graph::shortest_path_route;

pub use graph::validate_netrelation_references;

pub use graph::NetelementSide;

pub use graph::ShortestPathCache;

pub use spacing::calculate_mean_spacing;

pub use spacing::select_resampled_subset;

pub use viterbi::build_path_from_viterbi;

pub use viterbi::fill_path_gaps;

pub use viterbi::validate_path_navigability;

pub use viterbi::viterbi_decode;

pub use viterbi::GapFill;

pub use viterbi::SanityDecision;

pub use viterbi::ViterbiResult;

pub use viterbi::ViterbiSubsequence;

pub use PathCalculationMode::FallbackIndependent;

pub use PathCalculationMode::TopologyBased;

pub use candidate::*;

pub use probability::*;

Modules

candidate

Candidate netelement selection for GNSS positions

debug

Debug information export utilities for path calculation (US7)

graph

Network topology graph representation

probability

Probability calculation module

spacing

Spacing calculation for GNSS positions

viterbi

Log-space Viterbi algorithm for HMM-based map matching

Structs

CandidateInfo

Information about a single candidate netelement

CandidatePath

Information about a candidate path evaluated during calculation

DebugInfo

Debug information for path calculation (US7: T153)

NetelementProbabilityInfo

Probability information for a single netelement in the Viterbi result

PathConfig

Configuration for train path calculation algorithm

PathConfigBuilder

Builder for PathConfig with fluent API and validation

PathDecision

A decision point in the Viterbi path decoding process

PathResult

Result of train path calculation

PositionCandidates

Candidates considered for a single GNSS position

TransitionProbabilityEntry

A single transition probability between two candidates at consecutive GNSS positions

Enums

PathCalculationMode

Path calculation mode indicating which algorithm was used

Functions

calculate_train_path

Calculate the most probable continuous train path through the network

project_onto_path

Project GNSS coordinates onto a calculated train path (US2: T093-T097)