Derek Ellis

OC Transpo's New Age of Transit Data

It might not be apparent to everyone yet, but there are some big changes just around the corner to OC Transpo’s realtime data feeds and we’re already starting to see the benefits. A year ago, as part of the 2023 budget, OC Transpo announced that it would be overhauling its public-facing real-time GPS data feed to use the General Transit Feed Specification Real-time format (GTFS-rt for short) and I don’t think this has been getting the attention or hype that it deserves.

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A 16-Hour Transit Journey

I was playing around with a transit trip planning algorithm to estimate travel times on public transit in Ottawa when the algorithm gave me an interesting result: a 16-hour journey for a trip that should only take about an hour. At first I thought I had made a mistake when implementing the algorithm, but it turned about to be an interesting edge case instead. The Algorithm The algorithm that I implemented is the Round-Based Public Transit Optimized Routing algorithm, or RAPTOR for short.

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