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Maps that show time instead of space

spacetime-maps.vercel.app

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Re: Maps that show time instead of space

#21

Post by drusepth »

tasty_freeze wrote: post #13

I had this though many years ago, but unlike distance, travel time isn't necessarily symmetric, and so it isn't possible to represent time just by warping a conventional map as A->B and B->A will get the same warp. And if the map allows for different travel modes, like train vs driving, I think it breaks entirely. But this isn't to poop on the website -- I'm glad someone has taken the time to build a demo, even it it…

You can turn on arrows that update as you move your mouse around (assumedly, signifying an origin). Not sure exactly what they do, but they do hint at potentially taking asymmetric distance into account.

Re: Maps that show time instead of space

#22

Post by basil-rash »

nighthawk454 wrote: post #19
puzzledobserver wrote: post #17

This sounds conceptually difficult: Wouldn't the presence of one-way streets or airport security checkpoints, for example, mean that the travel time from A to B might not be the same as the travel time from B to A? How can a map then be drawn?

Right. There could be northbound traffic but not southbound for example. The answer is they must be symmetrizing the distances somehow. Alternatively, you could show the travel times _from a source location_ unambiguously, which might be more interesting for the average user (e.g. from home)

That still wouldn’t work in all cases. For instance if a ring of locations are all more accessible than a location they contain. Which applies to basically all suburbs.

Re: Maps that show time instead of space

#24

Post by ars »

adamcanady wrote: post #2

This is neat but the map by public transport time is probably non-euclidean because subways are like wormholes.

Not really - you have to wait for the subway, it also takes a finite time to travel, and it frequently stops. It can avoid traffic, but the actual MPH can be slower than a car when you include both those things.

Re: Maps that show time instead of space

#26

Post by lostlogin »

puzzledobserver wrote: post #17

This sounds conceptually difficult: Wouldn't the presence of one-way streets or airport security checkpoints, for example, mean that the travel time from A to B might not be the same as the travel time from B to A? How can a map then be drawn?

Good point.

And hills are rather easier in one direction too.

Re: Maps that show time instead of space

#27

Post by vincnetas »

markerz wrote: post #9

Interesting twist on what other people have done, namely show a heat-map of where you can go using public transit + walking within 5 min, 15 min, 30 min. time2reach https://map.henryn.ca/San%20Francisco NYC Subwaysheds https://news.ycombinator.com/item?id=36240264

It's called Isochrone map

https://en.wikipedia.org/wiki/Isochrone_map

Re: Maps that show time instead of space

#28

Post by avidiax »

danbruc wrote: post #6

See also isochron map [1]. [1] https://en.wikipedia.org/wiki/Isochrone_map

I prefer the typical isochron presentation over the warping. It's unfortunately hard to find free, public isochron maps, though. Some examples I've found:

https://www.targomo.com/developers/apis/isochrone/

https://direkt.bahn.guru/?origin=8503000

https://www.chronotrains.com/en

Re: Maps that show time instead of space

#29

Post by avidiax »

deadbabe wrote: post #16

If there was a place that was impossible to go to for some reason, would it become a sort of “black hole”? Are there any such black holes on earth? Or are they only theoretical.

It would not be representable, since even 1 unreachable point would have to have infinite area.

If you allowed the 2D map to become 3d, I suppose you could have an infinitely high spike or low trough.

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