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Assignment Output Files

Travel Model Two produces detailed assignment results showing how travel demand is loaded onto the transportation network infrastructure.

Time Pe### Network Performance Summaries

System Performance Report

File Pattern: output_summaries/network_performance_[TimePeriod].csv

Highway Metrics: - Total VMT by facility type - Average speeds by area type - Congestion duration and extent - Level of service distribution

Transit Metrics: - Total transit ridership - Average load factors - Service miles and hours - Passenger-miles per revenue-mile

Network Analysis Reference

For complete technical documentation on network attributes, analysis tools, and performance metrics, see the Network Analysis Reference page.

Screenline Analysisels travel across five time periods:

Code Name Time Range Duration
EA Early AM 3:00 AM - 6:00 AM 3 hours
AM AM Peak 6:00 AM - 10:00 AM 4 hours
MD Midday 10:00 AM - 3:00 PM 5 hours
PM PM Peak 3:00 PM - 7:00 PM 4 hours
EV Evening 7:00 PM - 3:00 AM 8 hours

Highway Facility Types

Highway links are classified by functional class using the @ft attribute:

Code Facility Type Description
1 Freeway Interstate highways and freeways
2 Freeway Principal arterial - freeway facilities
3 Arterial Principal arterial roads
4 Arterial Minor arterial roads
5 Collector Major collector roads
6 Collector Minor collector roads
7 Local Local streets and roads
8 Connector Highway ramps and connectors
99 Other Special facilities and other links

Note: Facility types 1 and 2 are treated as freeways in TM2PY’s reliability and delay calculations, while types 3-8 use arterial/road parameters.

Highway Assignment Outputs

Highway Network Files

MAZ Preload Networks

File Pattern: hwy/maz_preload_[TimePeriod].net

Description: Highway networks with MAZ-level demand loaded - Contains short local trips between MAZs - Shows local street utilization - Includes centroid connector flows

Final Assignment Networks

File Pattern: hwy/load[TimePeriod].net

Description: Complete highway networks with all demand loaded

Key Link Attributes: - @auto_volume - Total auto volume - @auto_time - Congested travel time - @auto_cost - Generalized cost - @v_over_c - Volume over capacity ratio - @cspd - Congested speed - @delay - Delay compared to free-flow

Vehicle Type Volumes: - @vol_da - Drive alone volume - @vol_s2 - Shared 2-person volume - @vol_s3 - Shared 3+ person volume - @vol_sm - Small truck volume - @vol_hv - Heavy vehicle volume - @vol_tot - Total volume

Intermediate Networks

File Patterns: - hwy/iter[X]loadEA.net - Assignment iteration networks - hwy/avgload[TimePeriod].net - Multi-iteration averaged networks

Highway Assignment Summary Files

Volume-Delay Function Performance

File Pattern: hwy/assign_summary_[TimePeriod].txt

Content: - Convergence statistics by iteration - Total vehicle-miles traveled (VMT) - Total vehicle-hours traveled (VHT)
- Average network speed - Relative gap convergence measures

File Pattern: hwy/selectlink_[analysis_name].txt

Description: Traffic volumes using specific highway facilities - Origin-destination patterns for selected links - Used for corridor analysis and impact assessment

Transit Assignment Outputs

Transit Ridership Files

Boardings by Line

File Pattern: trn/boardings_by_line_[TimePeriod].txt

Format: CSV with columns:

line_id,line_name,mode,boardings,passenger_miles

Content: - Total boardings per transit line - Passenger-miles by line - Mode-specific ridership (bus, rail, etc.)

Boardings by Segment

File Pattern: trn/boardings_by_segment_[TimePeriod].txt

Format: CSV with columns:

line_id,direction,stop_sequence,from_stop,to_stop,boardings,alightings,load

Content: - Segment-level ridership between stops - Directional passenger flows - Maximum load points identification

Transit Network Files

Assigned Transit Networks

File Pattern: trn/transit_assignment_[TimePeriod].net

Link Attributes: - @transit_boardings - Total boardings - @transit_volume - Passenger volume - @capacity_utilization - Load factor - @dwell_time - Station dwell time

Transit Line Attributes: - @line_ridership - Total line ridership - @headway - Service frequency - @capacity - Vehicle capacity

Advanced Transit Outputs

Station-to-Station Flows

File Pattern: trn/station_flows_[TimePeriod].csv

Description: Passenger flows between major transit stations Format:

origin_station,destination_station,passengers,avg_time,distance

Transfer Analysis

File Pattern: trn/transfers_[TimePeriod].csv

Content: - Transfer volumes at major stations - Transfer walking times - Mode-to-mode transfer patterns

Transit Path Flows

File Pattern: trn/path_flows_[TimePeriod].omx

Description: OMX matrices showing passenger flows by transit path and access mode

Congested Transit Outputs

When congested transit assignment is enabled:

Capacity Constraint Summary

File Pattern: trn/capacity_summary_[TimePeriod].txt

Content: - Lines/segments operating at capacity - Passenger denial statistics
- Crowding penalties applied

Reliability Impacts

File Pattern: trn/reliability_[TimePeriod].csv

Content: - Schedule adherence impacts - Passenger delay due to crowding - Service reliability metrics

Network Performance Summaries

System Performance Report

File Pattern: output_summaries/network_performance_[TimePeriod].csv

Highway Metrics: - Total VMT by facility type - Average speeds by area type - Congestion duration and extent - Level of service distribution

Transit Metrics: - Total transit ridership - Average load factors - Service miles and hours - Passenger-miles per revenue-mile

Screenline Analysis

File Pattern: output_summaries/screenlines_[TimePeriod].csv

Content: - Traffic volumes crossing defined screenlines - Mode split across major barriers - Directional flow patterns - Comparison with count data

Corridor Performance

File Pattern: output_summaries/corridors_[TimePeriod].csv

Content: - Travel times along major corridors
- Volume and speed by corridor segment - Parallel route usage patterns

Quality Assurance Outputs

Assignment Convergence

File Pattern: logs/assignment_convergence_[TimePeriod].log

Content: - Relative gap by iteration - Maximum link volume changes - Convergence criteria achievement

Network Validation

File Pattern: output_summaries/network_validation.csv

Content: - Comparison with traffic counts - Speed validation against floating car data - Transit ridership vs. operator data - Geographic distribution accuracy

File Formats and Usage

Network Files (.net)

  • Software: Emme transportation planning software
  • Content: Node/link topology with attributes
  • Size: 50-200 MB per time period

OMX Files (.omx)

  • Software: OpenMatrix library (Python, R, Java)
  • Content: Origin-destination matrices
  • Compression: Built-in HDF5 compression

Text/CSV Files

  • Software: Any spreadsheet or statistical package
  • Encoding: UTF-8
  • Delimiters: Comma or tab-separated

Processing Notes

  • Time Periods: All files generated for 5 time periods (EA, AM, MD, PM, EV)
  • Iterations: Assignment typically converges in 10-25 iterations
  • File Retention: Intermediate files may be cleaned up automatically
  • Coordinate System: California State Plane Zone III
  • Units: Miles, hours, passengers, vehicles