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Results: - added summary of initial GTFS extraction work.
== Results ==
Using the expanded capacities of the SimpleGTFSCreator=== Initial work:- sub-setting initial GTFS bus network file into sections to upgrade ===
TBCMuch work was put into the [[OSSTIP/SimpleGTFSCreator]] package in late 2014for extracting the 'abstract network topology and service' levels from anexisting GTFS timetable, in order to support modificationTo simplify the task, I first added some GTFS sub-setting tools by Geometric regionto reduce the number of relevant routes to process. By applying this using apolygon around "metro Melbourne", the area of interest for our networkupgrades package, it reduced the number of bus routes in the GTFS from 681 (for all ofVictoria) to 362. The subsetting script in SimpleGTFSCreator is called subset_trips_by_route.py,and the resulting GTFS file in the OSSTIP_Common_LargeFile_Archives Dropboxis in the subpath:- GTFS/GTFS-ExtractedData-201406/melb-bus-gtfs-2014_06-metro.zip I then wanted to extract just the bus routes specified for upgrading, toseparate GTFS files, and then create a further GTFS file for the bus routes weweren't going to upgrade. The strategy here is that the smaller GTFS files ofbus routes to upgrade could then be modified, while the remaining routes couldbe used as-is in calculations. This is because [[OpenTripPlanner]] has thenice feature of being able to combine an arbitrary number of GTFS files into asingle 'graph' for routing analysis (as long as each GTFS file has separatetrip, route etc IDs). So with further use of the SimpleGTFSCreator subset_trips_by_route.py script,I created these new GTFS files as follows:-* OSSTIP_Common_LargeFile_Archives/GTFS/GTFS-ExtractedData-201406/melb-bus-gtfs-2014_06-subsets/melb-bus-gtfs-2014_06-metro-smartbus.zip (9 routes)* OSSTIP_Common_LargeFile_Archives/GTFS/GTFS-ExtractedData-201406/melb-bus-gtfs-2014_06-subsets/melb-bus-gtfs-2014_06-metro-upgrade_to_smartbus-v1-20141111.zip (14 routes)* OSSTIP_Common_LargeFile_Archives/GTFS/GTFS-ExtractedData-201406/melb-bus-gtfs-2014_06-subsets/melb-bus-gtfs-2014_06-metro-non_smartbus_non_upgrade_to_smartbus-v1-20141111.zip (339 routes) So the next stage was to extract the generalised network topology and servicelevels from the first of these two files, so we could modify them and createnew upgraded versions. === Extraction process of generalised network topology and service levels === Discuss issues here :- deciding where routes started, looping, etc. === Revising for expanded route list === (Notes here). === Workflow for creating upgraded frequency of routes and producing a new GTFS file === === Issue with very long smartbus routes, and splitting of routes as a result === === Issues with speed-extraction of buses from timetables === === Outputs summary === (Where output GTFS files are).(Include an estimate of bus numbers in peak hour before and after the upgrades ...)
[[Category:OSSTIP]]
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