Tom 7 Radar

Pac Tom update: Polar adventures in data visualization

Sat, 19 Feb 2011 23:57:09 -0500

For those just joining us, Pac Tom is my now 4½-year project to run the length of every street in Pittsburgh. This update is about a new visualization of the GPS data I collect as part of the project. Behold the most radar-like image ever posted on Tom 7 Radar:

radial.pdf - click to have your face blasted with maths

I'd like to think that my data visualization experiments are self-explanatory, but this one does not have the ability to write or talk so I will do the needful. Each one of the orange lines is a Pac Tom running trip (now a slot-jackpotting 222 of them). The squiggles always start at angle 0, corresponding to 0 miles. They proceed around the radar circle clockwise according to how many Tom-sneaker miles the trip is, with a full revolution being 32 miles. At every point their distance from the center is based on the number of crow-flying miles that I am away from my home, with the outermost circle being 8 miles. Red dot emphasizes the end point. I hope that you appreciate the radial and angular gradations because those were fiddly to make in SVG, particularly the labels.

What can we tell from the graphic? Well, most trips start and end at home. This is obvious from The Rules, which require it. You can see that a bunch of them end about the same distance away; these are all me fizzling out at CMU's campus, where water and HVAC are plentiful, or sometimes where I used to leave my junk. You can also see that there's some consistency to the specifics of the routes both at the beginnings and end (like if you look at those 15–20 mile ones that end at CMU, you see the same jog patterns leading up to those ends, which is me taking the same turn on the way back). There's even a more bold orange laser at the beginning, which basically corresponds to me taking any efficient route away from my house, regardless of where I'm going (it is roughly an Archimedian spiral, where after 5 miles of running I'm about 5 miles away from my house). The most interesting thing to me is that there really is a characteristic shape of a Pac Tom run when plotted this way. A typical runner's route (out and back) would be a prolate ellipsis, actually maybe more like a vesica piscis if the runner gets to the summit overlook or no tresspassing sign or whatever and turns right around. My shorter earlydays runs, which are hard to see because they're all bunched up on top of one another in the South-East octant, are kind of like that actually. But the canonical Pac Tom run now is obovate like a ginkgo leaf, where I run away from home then zig-zag back and forth for many miles, creating the tiny leaf teeth at approximately the same distance, then run back home. There's not even any reason why these would have to be leaf-shaped at all; you can see the few Pittsburgh Marathons in there (those count), which are more like abortive Spirographs.

I had appendix surgery (meaning they just cut it out and threw it in the biohazard) in September and then a work crunch that disrupted my running for a while, but I'm now back to it. I'm getting in decent shape again for the marathon, which I am excited about mostly because of the costume plans. I just polished off large distant neighborhoods Sheraden and Elliott (after a fairly heartbreaking trip where I thought I had at great effort finished, but had missed a tiny 50-foot segment, so I had to go many miles out of my way to get that one yesterday, in really OCD-affirming style. Having done that is actually one of the diagnostic criteria in DSM VII.) and the remaining cleanup to do on the South Side is pretty light and much closer to my home. I think I can be done with those with maybe two months of regular running, and maybe even finish the North Side, which is all that's left, by the end of 2011? 4500 miles in 27 days 15 hours of running, so far. You may track my progress via the graphics at the Pac Tom ultimate cybersite.

Pac Tom September update

Sun, 12 Sep 2010 00:26:20 -0400

Time for another update on my project to run the length of every street in Pittsburgh, called Pac Tom. It's all about the map:

	Pac Tom project:
	site · all · map

Also available is the same map in PDF so that you can pinch to zoom. Over on the right (known to cartographers as "East") you can see Pac Tom Level 1, totally all done. I've been hard at work on the stuff South of the Monongahela since I finished Level 1 almost two years ago. It's hard because it's far from my house (see rules and regulations) and crazy hilly. You can see that I've made a lot of progress either just by the superbrite color lines all over everything (btw that image above is about 136 square miles, about 140 feet per pixel) which is where I went, or by comparing to last time, or by me being more specific:

Neighborhoods totally done (level 2): Banksville, Beltzhoover, Bon Air, Brookline, Carrick, Chartiers City, East Carnegie, Esplen, Fairywood, Hays, Knoxville, Lincoln Place, Oakwood, Overbrook, Ridgemont, St. Clair, Westwood, Windgap.

Total running events (this includes Pac Tom, training, races, and 3D World Runner): 734
Total time recorded: 25 days, 23:15:38
Total distance: 4230.118 miles

But actually what I really wanted to show you was a newer map, which has been on the Pac Tom site for a while but I have never explained. It's the shortest paths map:

Well, at this view it just looks like the regular map vomited a rainbow all over itself. What's going on is that this is a graph of all of the places I've been (each individual GPS waypoint), connected by heuristics (like they were consecutive in a trip, so I actually ran between them, or they appear to be near enough to imply that I could run between them) and then I compute the shortest path from each point back to my home. Here's a zoom up:

Bonus points if you recognize the neighborhood! See all those fingersnakes reaching up to meet one another? Those aren't dead ends, they're the farthest away from my house I can get on those roads (the leaves in the minimal spanning tree rooted at my house). On one side, the shortest path is to go South, but just a few feet away, the shortest way is to go North. (My house is Southeast from here.) I spent a lot of (fun) time writing this code partly in the hopes that it would teach me about better ways to get out to distant neighborhoods, but it turns out that on city streets (especially grids), the shortest path on foot is usually pretty obvious. Even when it's not, the difference rarely exceeds 100 feet. The most interesting places are probably choke points, like bridges:

Pretty much everything nearby points up this bridge. The colors by the way are not gratuitous; they indicate the physical heading that I should be running on that segment to decrease my distance to home. Green means East, red means North, violet means West, cyan means South. This is meant to emphasize the break-even points described above. Here you can see from the thickness of the lines (which just comes from having lots of runs through there, with GPS noise) that I don't usually take the Birmingham Bridge, even though it would save me about a South Side block's width (that's the pink stuff: Turn around!) I usually prefer the Hot Metal Bridge to the East because it's got better pedestrian access and also my brain autopilot is accustomed to the area, having run it like a hundred times. Unfortunately it's hard to get route preferences (and other stuff like elevation change) incorporated into the formulas. So, rainbow brite indeed but not actually that useful. The maps are updated automatically after every run onto the graphics page. You can check out the source code which of course is mostly calls out to general-purpose libraries for loading GPS data and computing fine-grained distances on the earth pear's surface and undirected graphs and snapping the neighborhood boundaries to be exactly perfect, and outputting the SVG, all of which I of course wrote myself even though it probably or certainly already exists because have you MET Tom?

Pac Tom website and Level 2

Sun, 21 Feb 2010 12:44:01 -0500

I'd like to introduce you to the Pac Tom website, where I'll be organizing my project to run the length of every street in Pittsburgh. New look, look:

If you go there right now you'll see this very blog post, which contains a picture of the site, which is what you're already seeing, which etc. Maybe you got here from somewhere else and you're wondering why the site tells you that you should visit itself. That's cuz it shows all Pac Tom news, and this is Pac Tom news. But there's other better stuff there too, like a new description of the rules, downloadable KML files of my routes, and brand new maps. Here's the main one:

	Pac Tom project:
	site · all · map

In post 1039 I congratulated myself on finishing Level 1, which is all the roads between the Allegheny and Monongahela rivers (conspicuous sinuous voids in the map above). That was over a year ago, and since then I've made significant progress on Level 2, which is the rest of the city. Each of the colors in the map above is a different trip, though some trips get the same color because there aren't that many colors and they're assigned randomly. I finished off the remote colony of Lemingon-Lincoln-Belmar that's across the river to the far Northwest in one go. (It's pretty weird that this is part of the same neighborhood or even part of Pittsburgh; it's almost entirely a shopping plaza. Must be a tax thing.) The rest of the year has been spent on the neighborhoods to the south of the Mon.

This is way harder than Level 1 was. Obstacles: It's about 6 miles of running just to get from my house to new roads, which I also have to do on the way back, so a minimal trip is 12 miles; they're usually more like 20 so that I can get deep down there and then cover some streets. You can tell from the map that I've been favoring the roads that closest to the borders. I like to do this so that I can "finish off" the periphery and not have to worry about it again; on the way there and back I can pick up some new roads shotgun style. (I'm almost done with South Side flats only via taking different routes through it on my way to other places.) The furthest points imply about a 30-mile round trip (you can see them way off to the West). I haven't done those yet, but I have done some 30-mile trips, so I know it will be possible and painful. Obstacle #2: This area of the city is ridiculously hilly. Level 1 sure had some steep streets but the South Side and West End are worse. Just getting there means running up the Slopes or Mt. Washington, and then the hills roll on. Garmin Connect, which is what I hook my GPS into, pretty much always assumes that the physical activity I'm doing is "Stair Climbing" based on the elevation change. The steepest paved road in the world is there, in Beechview! I'm not complaining, though. I love it.

One of my favorite things to do with the thousands of miles of GPS data that results from the project is various visualizations and computation. There are some more maps on the site and some more coming. I'll post about these soon.

Pac Tom Level 1 Complete, trophy

Sat, 30 Jan 2010 11:21:22 -0500

pac tom level 1 trophy.pdf

	Pac Tom project:
	site · all · map

Hey, this post is to officially announce that I completed Level 1 of my Pac Tom project. That's a big deal for me but I'm kind of over it because I finished over a year ago, in November 2008! I've been strangely silent on the project since I announced almost being done in the August 2008. It's part of a weird pattern of behavior where I finish or almost finish big projects but then never announce them because my announcement ambitions exceed my announcement wherewithal, which would be such a tiny fraction of the total effort expended (which is weird) so I never actually announce them. This particular case is strange because I'm well on to Pac Tom Level 2, spending many hours every week busting my ass on it in various ways. I'm trying to fix this behavior. Pac Tom Level 1 is done! Soon, the Pac Tom website and my substantial progress on Level 2.

Pac Tom is my project to run the length of every street in Pittsburgh, Pennsylvania, USA. I've been doing it for many years now, accounting for many thousands of miles and many hundreds of hours of running. Level 1 is the area of the city between the Allegheny and Monongahela rivers (see map above), which is 23.5 square miles. Those black lines are the routes I ran, tracked with my wrist-worn GPS device. I always start or end at my home or work, usually both. The background map is my old Map of Pittsburgh Neighborhoods which I made for Wikipedia. Click for a PDF so you can zoom to your heart's content, as long as its content does not exceed the limits of IEEE floating point. I have new maps now which are not as sloppy, but also not as colorful.

And then I have to do this:

ACHIEVEMENT UNLOCKED
Every street, continental Pgh

Pac-Tom Update: October 2008

Sat, 11 Oct 2008 16:03:15 -0400

800×645 version

	Pac Tom project:
	site · all · map

Okay, we'll make this one quick. I spent a lot of time this summer training for races, which cut into this project to run every street. I still occasionally made some progress on that, and now that I'm back in town without any races coming up I'm on it full-time. Like I mentioned last time, the name of the game now is to finish up those scattered spots I've missed and eliminate neighborhoods one at a time, concentrating on the more distant ones first. Newly added to this list are all of the Oakland neighborhoods and Squirrel Hill South, which is the largest neighborhood in the city (by area), and really hilly. Phew! The finished neighborhoods are darkened in above and pink are individual marked-for-death roads. It certainly looks like I'm almost done, huh?

Total distance: 2208.5 miles.
Total time: 12 days, 15 hours, 15 minutes.