nfitz
Superstar
The question is, how do you design the algorithm, particularly when you only know the tap-on location.I get that that is the way it is....I just don't see that it should be. I just see a big difference between an A-B-C trip and a A-B-A trip.
Say you start your trip at Finch station, and you go to King station. But you stop at Eglinton to buy something particular. How does Presto know the difference between a return trip starting at Davisville,and a continuation of the trip.
Even on buses, if it knows direction. Let's say you normally take the Don Mills bus from O'Connor to York Mills. But you have to pick up something at Eglinton and Bermondsey. So you take the bus to Eglinton, transfer to the frequent Eglinton Bus 4 stops to Bermondsey. Grab what you want, jump on the Eglinton bus bac, and then on another Don Mills bus to York Mills. How does Presto know that the tap on at Eglinton/Bermondsey is a continued trip, rather than a return trip?
Without tap-off on buses it's impossible. And even with tap-off, it's a programming nightmare.
Montreal has not introduced 2-hour fares on their system, despite the Opus card. The transfer is good for 2-hours, but you can't reuse it on the same bus line, or re-enter the Metro. I can only assume that the concept of short-turns doesn't exist there (I certainly don't remember short turns in Montreal, unless the bus broke down!). I'd love to see more details about how transfers work there ... I assume there are many ways to game the system.
In Toronto not re-entering the subway system would be an odd restriction - there are trips that are faster to take 2 subways, and a bus/streetcar in the middle. Davisville to Dupont station is one. Greenwood to Leslie is another Though offhand, I can't think of one where you'd have to use the subway turnstiles.