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opentripplanner / OpenTripPlanner

An open source multi-modal trip planner
http://www.opentripplanner.org
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Standalone graph builder should run PruneFloatingIslands after loading GTFS #1349

Closed mattwigway closed 10 years ago

mattwigway commented 10 years ago

Currently, OSM data is loaded, then PruneFloatingIslands is run, then GTFS is loaded. PruneFloatingIslands works better after transit data is loaded, because small islands may be ok if there are transit stops on them (see #429).

abyrd commented 10 years ago

The conclusion I see in #429 is "I doubt that pedestrian islands with less then 20 nodes are too common of an occurrence. Even less have ferries to them. So I don't thinks it's a problem worth spending time on."

The problem with linking before pruning is that almost all small islands in OSM are mistakes. Once they have been linked they persist as islands. By cleaning them out before linking we ensure that the transit stops are accessible from the rest of the street graph.

mattwigway commented 10 years ago

Good point. Closing as wontfix.