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World Airports Voronoi (2014)

jasondavies.com

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Re: World Airports Voronoi (2014)

#61

Post by binarymax »

barrkel wrote: post #44
drostie wrote: post #39

Earlier quoted context omitted.

I'd guess more likely that they are chocolate nozzles -- it seems more straightforward to me to produce a precise chocolate "cup", pour or place the filling inside of it, then pipe a chocolate "lid" onto the cup. Presumably the multiple nozzles of chocolate would help it to settle flatter faster. Edit: there's a video on Facebook that covers the whole process in a minute. My hunch is partly right: the wrapper and cho…

I wasn't aware there was anything below the chocolate-like surface, so I understood you to be saying the same thing as grandparent.

Which country are you in? If you like chocolate and peanut butter (and sugar), I recommend trying a Reese's cup :)

Re: World Airports Voronoi (2014)

#64

Post by lisper »

This diagram is oddly selective about which airports it includes. It has some class D airports (Modesto, Santa Maria) but not others (Palo Alto, El Monte, Fullerton). There is no pattern that I can discern other than eliminating airports that are too close to each other, which kind of defeats the purpose of this exercise.

Re: World Airports Voronoi (2014)

#65

Post by lisper »

evrydayhustling wrote: post #63

I bet the vertices are correct, but shouldn't the lines in between them look like curves? They are projected solutions for the points that are equidistant by great circle distance to two airports, so I think they should themselves be great circle arcs.

They are great-circle arcs, but the presentation is a projected sphere, so the lines in the center will look straight because you're looking down on the curved part. Zoom out and look at the lines near the edges.

Re: World Airports Voronoi (2014)

#66

Post by tzahola »

pvg wrote: post #40
tzahola wrote: post #37

Earlier quoted context omitted.

It is related. When rocks cool, crystals start to grow from multiple seeds because of thermal/chemical impurities. If the material is sufficiently homogenous in composition and temperature, then the crystals from different seeds will grow at the same rate. When they grow into each other, a boundary between different crystal domains will form. Crystal domains formed this way look like Voronoi cells. The peanut butter…

I know the former bit. I don't see how the latter obviously follows. You're basically saying it's related because it looks the same but it's clear from the picture it looks the same.

crystal seed = peanut butter nozzle crystal growth = peanut butter flow

Imagine that the peanut butter is not poured from the top, rather coming from holes at the bottom of the cup. Initially there's a radially growing patch of peanut butter around each hole. When the peanut butter patches grow large enough, they touch, and form an approximately straight boundary (if the flow rate is equal for all outlets) like the boundary between crystal domains.

Of course, peanut butter is a fluid, so its dynamics are ultimately different from crystal growth, but at this scale, it produces a very similar phenomenon thanks to its high viscosity.

Re: World Airports Voronoi (2014)

#67

Post by evrydayhustling »

lisper wrote: post #65
evrydayhustling wrote: post #63

I bet the vertices are correct, but shouldn't the lines in between them look like curves? They are projected solutions for the points that are equidistant by great circle distance to two airports, so I think they should themselves be great circle arcs.

They are great-circle arcs, but the presentation is a projected sphere, so the lines in the center will look straight because you're looking down on the curved part. Zoom out and look at the lines near the edges.

Thanks, you are totally right. Was zoomed in too far.

Re: World Airports Voronoi (2014)

#68

Post by pdelbarba »

This is interesting because normally I'd assume this would just follow population density (Europe, the NA, Japan, see xkcd.com/1138) but India and China barely have any airports relative to their populations. That's a lot of traveling just to get to an airport.

Re: World Airports Voronoi (2014)

#69

Post by rando444 »

lisper wrote: post #64

This diagram is oddly selective about which airports it includes. It has some class D airports (Modesto, Santa Maria) but not others (Palo Alto, El Monte, Fullerton). There is no pattern that I can discern other than eliminating airports that are too close to each other, which kind of defeats the purpose of this exercise.

I noticed they included most all the tiny regional airports in Iceland, but left out ones like Kulusuk in Greenland, which receives international air traffic.

Re: World Airports Voronoi (2014)

#70

Post by mortigi »

lisper wrote: post #64

This diagram is oddly selective about which airports it includes. It has some class D airports (Modesto, Santa Maria) but not others (Palo Alto, El Monte, Fullerton). There is no pattern that I can discern other than eliminating airports that are too close to each other, which kind of defeats the purpose of this exercise.

Agreed - this leads to many of these subset areas being displayed as much larger than they should be, while others should be larger. Either eliminate class D, or don't - to be inconsistent seems pretty pointless.
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