How Graphviz thinks the USA is laid out (2021) | Hacker News Reader

How Graphviz thinks the USA is laid out (2021)

shitpost.plover.com

200 pointsbjourne42 comments

> [ Note: this is where I lost interest and stopped writing. ]

Kudos for actually bothering to publish the damn thing. Many people (myself likely included) would have spent hours agonizing over minute unimportant details and ultimately never actually get it out the door.

I've never seen that line before and that might motivate me to finally keep a blog. I like collecting thoughts, but I often dislike the polishing required to turn thoughts into a complete blog post.

Sometimes one just wants to do the 80% of the effort and be done with it.

You should defin

The remaining 20% of the job takes another 80% of the effort.

To me, it feels like sloppiness presented as a virtue.

Even if you have lost interest, there are more civil ways to close a text.

If you had said ’lazyness’ instead of ’sloppiness’ it would have become a higher order joke.

Higher order if misspell ‘laziness’? Don’t get. I am so unsophistimacated :(

"According to Larry Wall, the original author of the Perl programming language, there are three great virtues of a programmer; Laziness, Impatience and Hubris

Laziness: The quality that makes you go to great effort to reduce overall energy expenditure. It makes you write labor-saving programs that other people will find useful and document what you wrote so you don't have to answer so many questions about it.

Impatience: The anger you feel when the computer is being lazy. This makes you write programs that don't just react to your needs, but actually anticipate them. Or at least pretend to.

Hubris: The quality that makes you write (and maintain) programs that other people won't want to say bad things about."

[0] https://web.archive.org/web/20150205083209/http://threevirtu... [1]

[1] NB that threevirtues.com, in this late year, has been taken over by some sort of sea salt seller

Ah! Thorough, helpful and interesting answer.

Given the author, higher order jokes seem especially appropriate.

I noticed that, too, and realized how thought-provoking the ability to just say "OK, I'm done" really is. That, and marking (though not actually serving) as `Content-Type: text/shitpost` really demonstrates that the author is more interested in sharing the technical aspects of his discovery than in needless elaboration and commentary.

>sharing the technical aspects of his discovery than in needless elaboration and commentary.

He should start a recipe blog.

I believe that people should be a lot more trigger happy when it comes to writing stream of consciousness and sharing it.. but at the same time we should be structuring our communication tools around iterative refinement so that the reader can pick up the slack and make the adjustments they feel make sense and slowly the final version of the text emerges from this process.. Right now we do a lot of denial of service attacks on science because we've raised the bar to an anxiety inducing extent, I believe it is important to bring it back down again so that we can all be humans.

I wonder if some of the oddities generated by the "neato" and "fdp" engines (e.g. SC behaving like a peninsula) would be addressed by also modeling the borders with the oceans (i.e. the coasts) and with other countries -- just like he modeled the borders between states (e.g. the ocean would "push back" on SC).

Discussed at the time:

How Graphviz thinks the USA is laid out - https://news.ycombinator.com/item?id=25611053 - Jan 2021 (80 comments)

How Graphviz thinks the USA is laid out - https://news.ycombinator.com/item?id=25604462 - Jan 2021 (4 comments)

It bothers me that the graphviz algorithms almost always feel to me doing a poor job of laying out nodes. Like here in the neato layout you have both nodes overlapping eachother and edges overlapping with nodes, both which should be avoidable, and in fdp there is also some overlap and additionally RI and WA placements are "wrong" (non-planar). sfdp is just a mess, and twopi is even worse. Is there any software that works better?

I realize that this might be fundamentally difficult problem, but it just feels odd that there hasn't been much improvement in this area.

I believe you can explicitly set "overlap=false".

That's right. The initial layout in neato (which is really statistical multidimensional scaling) treats nodes as points, then draws shapes on top of the points without considering overlap. overlap=false or overlap=prism invokes a second layout phase as described in this report: https://link.springer.com/content/pdf/10.1007/978-3-642-0021...

There may be better methods by now - it would be a good intern project to look at that.

It would be a good idea to simply take the state centroids as an initial placement and onyl run the overlap removal phase.

In edge routing, we were really impressed with the "repulsive curve" work by Keenan Crane at CMU, https://www.cs.cmu.edu/~kmcrane/Projects/RepulsiveCurves/ind... - scroll halfway down for the graph layout examples.

Wow, that's really fascinating. I never knew there was a connection between knot theory and laying out graphs.

I tried this with the London tube map in 2004. It was not entirely successful[1].

[1] https://rjp.frottage.org/codeblog/tubemap_20041203_1745.html

Looks mostly decent, just needs vertical and horizontal mirroring. Also I don't understand the colour choice, sometimes it switches from one to another on the same line (Barking -> Upney).

> sometimes it switches from one to another on the same line (Barking -> Upney)

Beats me. I just ran the Perl to convert the list of tubes to the neato format and it made them both green. Maybe I generated the images and then later fixed a bug in the generation? I could probably check but I'd have to resurrect Trac from 18 years ago and ... uh.

(See also EastCote and Eastcote on the map where there's now only EastCote in the data file.)

November 2005

[ Note: this is where I lost interest and stopped writing. ]

I probably broke hobix with a Ruby upgrade and started a spiral into blog engine madness...

I wonder if adding River Thames crossings will improve things. That's a major component of the tube map.

Huh, didn't think of that. I'll give it a go later.

Typical metro maps are quite complicated to automatically calculate. At least I know of no efficient algorithm and force-directed layout doesn't really work, since you want the stations in roughly the right place, especially relative to other stations. A colleague tried something based on a paper a few years ago [1], alas it only really worked with a commercial ILP solver. We've tried an open-source one a year before that and could only get results in acceptable time for three lines or so.

I think most tube maps are hand-arranged, perhaps with some algorithmic help, but oftentimes you also have to fit a specific aspect ratio or shape (because the greater metropolitan area is also shown on the map, along with fare zones), which I don't think any algorithm currently does well. And the manual approach can result in niceties like the actual circle around the city center here: https://www.rsag-online.de/fahrplan/liniennetzplaene

[1] https://www.yworks.com/blog/automatic-metro-map-generation

I couldn't find any comments from previous posts pointing out that the dot output uses rank which as things progress as listed increases in value unless you say rank=same on all edges.

Four corners is a square, but I wonder: why not an X? If you can literally step from Arizona to Colorado I’d say that they’re connected. Anyway, cool maps. I love how they help promote the kinds of default graphziv layouts in a commonly understood dataset. Well done.

I think it's because you are going to cross through New Mexico or Utah first (unless we represent "you" as a point, line, or other zero-width object, and have it traverse a 45° line through the infinitely small point of intersection of the four states—which I'd say would be a kind of generous model for any path that happens in real life).

What a great lead. Spoiler alert: I've been to Four Corners.

I've also flown over Labrador, and would never say "I've been to Labrador" as a result. While I have also visited Indiana, I have travelled through it by rail or car much more often, between Chicago and Michgan. If I had only done this, I would probably say "well, technically I've been to Indiana, but I drove right through it".

Leading me to the "boots on the ground" theory of visitation: a place has been visited if your feet/footware make firm contact with the ground, or an object anchored to the ground in a durable fashion.

At Four Corners, it's quite possible to step directly from New Mexico to Utah, and from Arizona to Colorado, without setting foot in the other two states in the quadrant.

At most, you fly over Arizona and Colorado, on the way from New Mexico to Utah. As we've established, flying over a place is not a visitation.

Which brings us to the fun part! Every tourist who visits four corners walks a circle around the States. Only some, and most children, do the jumps!

If you don't do the jumps you can't say "I've been to Utah straight from New Mexico", which is too bad, since that and its dual are the only topologically interesting part about Four Corners! The other pairings share long borders.

Also, Monument Valley is breathtaking. Truly a wonder of the world.

I had a lot of fun using graphviz to create a call graph of my C++ code, thanks to clang.

Unfortunately, I was not able to generate something readable.

Two curious points:

1. I see it thinks Hawaii is effectively in canada. I'm assuming this is because the default behavior for unlinked nodes is for them to end up near the top in empty space?

2. Why are there no edges connected to Arkansas as it is within the main continental US?

AK is Alaska.

Oh.. I think I had a brain fart when writing this. Thank you

It's probably because the US is generally wider than tall but the NE US has many more states, so that leaves an otherwise empty space in the top-left.

Is there anything interesting in how neato came to orient this correctly?

It is surprising though maybe they gave a good initial placement?

Neat for trivia. TN and MO are tied at 8 for the most connected state.

RI/NY doesn't seem right

It's right.

The border isn't on land; it's a nautical boundary-there's a line from just south of Stonington CT, running between Montauk Point (NY/L.I.) and Block Island (RI).

I was wondering about this same thing, makes perfect sense that there’s a nautical border between Long Island and Rhode Island. Thanks!

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