Integer overflow

[simont]

I went into town at lunchtime to run errands, and parked in Lion Yard. Rather to my surprise, this was a completely different car park from the one I parked in last time I went to Lion Yard: the Grand Arcade building project has evidently progressed to the stage where they can activate the new piece of car park and (presumably) shut down the old one to start refurbishing that.

It's mostly just a car park, but it has one or two notable oddities in its design. Firstly, even its lowest floor is a long way up in the air, and access is via an extremely long helical ramp which guarantees that by the time you get up to the car park itself you won't have the faintest idea how you're oriented relative to the shops, and hence you don't know which set of lifts to use to avoid having to walk round the entire outside of the building to get to where you really wanted to be. There seemed to be a dearth of useful signs to tell you what was where; perhaps they're going to put those up later.

Secondly, and most delightfully, there's a pair of adjacent lifts on the south side. One is labelled ‘South Lift, Levels 2 – 4’. The other sign, and I had to stare at this for a couple of minutes before I convinced myself that it really said what I thought I was seeing, reads ‘South Lift, Levels 2 – -1’. Really. Two to minus one. On a huge, beautifully presented, professional-looking sign, and moreover on a sign ten metres away from one that makes sense. To add to the visual jar, the dash and the minus sign are at different heights, which is presumably just a question of how the font they were using happened to be designed.

I'm quite tempted to go back with a camera and take a photo of it before they realise and correct it.

Comments

[aldabra]

Haaang on. They're labelling a lift "floors 2 to 4" on a floor which isn't in the interval [2...4]? But it is in the interval [-1...2]?

So, floor 2 is the first floor of carpark? And therefore the default ingress to the arcade. So clearly you label everything with reference to floor 2. I think these signs [2...4] and [-1...2] (ok, [2...-1]) ought to be installed on level 2. But then clearly lift [2...4] ought not to be instantiated on the ground floor.

What happens in -1?

[simont]

They're labelling a lift "floors 2 to 4" on a floor which isn't in the interval [2...4]?

Well, yes; they're telling you what floors it'll take you to other than the one you're currently on. That may be mathematically dodgy but common-sense-wise it's perfectly reasonable!

[feanelwa.livejournal.com]

Oh right, I see. So the lift for 2-4 has a door on the car park floor, and it takes you up to 2, 3 and 4, and the lift for -1-2 takes you to the basement, ground floor, 1 and 2, one of which is the floor you're already on in the car park. Shops are taller than car parks, so I suppose the bottom layer of shops covers floors G and 1, and the top layer of shops is floors 2 and 3 and possibly 4. So if you know you want to go to the top layer of shops or car park levels 3 and 4 you get in that lift right there without having to pootle about with people who are going to the bottom floors, and if you are going to the bottom floor to work your way up you are assumed to be Slow and therefore can share your lift with the people who got the bus or parked on floors G and 1 and the basement.