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LU end-to-end journey data
On May 3, 1:24 am, James Farrar wrote:
On 2 May 2007 13:25:17 -0700, MIG wrote: On May 2, 7:05 pm, James Farrar wrote: On Wed, 02 May 2007 18:38:56 +0100, Paul Corfield wrote: And *as* you are a genius I am sure you'll be able to work out what a zig zag is ;-) Zig-zag is three uses (in-out-in or out-in-out or purchase-in-out) in quick succession, right? What use would that be to anyone? I mean, what scam would be pulled by that means? When I go through the barriers at Charing Cross platforms 1 - 4, just miss my train and have to head for platform 6 for the next one, I've never understood why the gates won't let me out. What scam is being prevented by it? If zig-zag is allowed, it's tantamount to allowing passback. Example: Passengers A and B are travelling together. B has a valid ticket, A does not. B goes through the "out" gate using the ticket, then puts the ticket back through an "in" gate, then passing the ticket to A who uses it to exit. Allowing out-in-out (or in-out-in, the logic runs exactly the same) is tantamount to allowing out-out (or in-in) in quick succession, i.e. passback. Example: Passenger A (who has travelled by rail from long distance) is meeing friend B (who has arrived on foot) at a gated station. A travels without a ticket, knowing that if the gate is closed, B can buy the cheapest single ticket from the machine, use it in an "in" gate and then pass it to A to use it to exit. Elimination of purchase-in-out is necessary to prevent this My Charing Cross example involves a travelcard. If I was meeting someone who had travelled without a ticket, I could just pass it over the exit gate to them, far less ostentatiously than by backing out of the entry gate and passing it to them with someone trying to enter behind me. If there were no restrictions, people would just pass the ticket back, so there would be nothing to be gained by putting the ticket through an extra time. Given that there are restrictions that prevent any kind of successive passes at the same gateline, there is still nothing to be gained by passing the ticket through an extra time, and no need to program against it, because it's already ruled out by simpler restrictions. I must be missing something. |
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