Hack 5. The Road Less Traveled by in MapQuest

The specified route may get you where you want to be, but what about that other road?

The interstates are fast and clean, but the Blue Highways are more than a routing choice. The motto of the Blue Line fan is "There is more than one way to get there." One morning I happened to stagger into life at 9:00 A.M., fretting about the coming day. I was in Portland, Oregon, at the O'Reilly Open Source Convention and wanted to get home to Sebastopol, California. The obvious and "simple" route is 656 miles down I-5, past Sebastopol, then a swoop up and around the San Francisco Bay and up 101.

Frankly, it is one of the prettier interstate drives around, but it is still an interstate drive. My car mates were lobbying hard for the purely scenic route along Highway 101. To make things a tad more complicated, we had to pick up yet another passenger in Eugene, Oregon. How much pain and time was that Blue Highway scenery going to cost me? I needed a way to quantify the tedium of the longer journey.

Everyone uses MapQuest to prepare monolithic routes, a single routing that describes the whole trip. I wanted to split that into segments and compare the time and distance of each segment. If you have connectivity, you can create multiple views of the same journey in MapQuest, or use the same techniques in any mapping service that provides directions. As an aside, the connectivity in Lithia Park in Ashland, Oregon, is stellar. The drive from Portland to Ashland is easy, so it is convenient to stop in Ashland to download a bunch of code to play with on the rest of the trip.

1.6.1. Get the Right Scale

Picking alternative routes requires that we can see them! Since this trip is so long, we can't get enough detail to compare the I-5 and coastal alternatives on one map. The map in Figure 1-7 is useless for alternate route determination! In order to compare alternatives, we need to split our journey into at least two more detailed parts.

Figure 1-7. The scale is wrong, and no alternatives appear in the overview map

Here we can use the "Open in New Window" trick of most browsers. Navigate through MapQuest to a map that shows your complete trip and then right-click (Ctrl-click on the Mac) on the "+" sign of the Zoom tool that is along the right side of the map. In most browsers, this will open a right-click context menu that includes the option to open the link in a new window.

That's more like it! In Figure 1-8, we can see the coastal route, and we have enough context to know what questions we want to ask next. One key to effective use of electronic maps is to zoom in close enough to see the important details, yet far enough out so as not to get lost in the detail. It is a balancing act for each exploration.

Figure 1-8. Oregon from Eugene down

Now zoom in so that you have two identical views of the same map. Next scroll the original, less detailed map down by clicking on the arrows on the bottom (south) side of the map. The idea is to have windows of each segment of the trip with enough overlap so you can mentally stitch the maps together (see Figure 1-9).

Figure 1-9. Northern California, showing the route down I-5

In this case, I need a third map to capture that important area south of Mendocino! So I repeat the process of opening a new window to get three browser windows that, between them, cover the whole trip. In this case, I right-click on the arrows pointing south to open a new window that includes Sebastopol (Figure 1-10).

Figure 1-10. The rest of the California leg of the trip


1.6.2. There's More Than One Way to Get There!

We want to explore the maps to get ideas about what we want to experience. This is the fun part of the process! First consider your constraintsin our case, we need to pick up Gene in Eugeneand then look at what is possible. Eugene is on I-5, so how would we get to 101? Looking at the Oregon portion of the trip, there are two seemingly reasonable ways to get to Highway 101 on the coast. We can go directly to Florence, or head down Highway 5 to Grant's Pass and then take the little red road to Crescent City in the extreme northwest corner of California.

So let's compare these two segments. Open yet another MapQuest window by right-clicking on "New Directions," and let's see what MapQuest has to offer about a trip from Eugene, Oregon, to Crescent City, California (Figure 1-11).

Figure 1-11. Directions from Eugene, OR, to Crescent City, CA

Interesting! MapQuest picks the interstate for the majority of the trip. The alternative from Eugene images/ent/U2192.GIF border=0> Florence images/ent/U2192.GIF border=0> Crescent City is ignored.

1.6.3. Using Estimated Time

A note on Estimated Time and using trip segments to get an idea of the heinousness of a route: everyone has a different idea of how long a trip will take, and none of the estimates are "correct." In this case, MapQuest is suggesting an average speed of about 56 mph for the whole leg (223 miles divided by 239 minutes times 60 minutes per hour = 56 miles per hour). Breaking that down, it is 58 mph for the I-5 portion.

I know that I can drive faster on the interstate, but does that mean I'll get there sooner? Who knows! I have a new camera and I'm snap-happy. Maybe we'll stop every 10 miles on either route. Perhaps there is an interesting museum right off the interstate. MapQuest can't tell us what we'll do, but using their idea of travel time and average speed will help us out. See [Hack #7] to get another trick to use with MapQuest.

1.6.4. Tricking MapQuest with Multiple Routes

MapQuest always gives us the "best" route, where "best" is set by their programmers. If we want to compare different routes, we need to break up our original trip into sections so that MapQuest is forced to give us our preferred route, and then we need to add up the segments.

For example, when we asked for the route from Eugene to Crescent City, MapQuest routed us through Grants Pass. The service won't give us a route from Eugene to Florence, on the coast, and then down to Crescent City. But MapQuest will give us the route from Eugene to Florence, if we ask nicely, and then the route from Florence to Crescent City.

So how do the different options compare? The times and distances for these two options are shown in Figure 1-12.

Figure 1-12. Comparing I-5 with the coastal route

The bottom line? The coast route is only 22 miles longer. No problem. It is also nearly an hour and a half longer, and the average speed is 11 mph lower. Ultimately, we elected to go straight down I-5, and we didn't get home until 4:30 A.M., so I'm just as happy that we managed to avoid driving until 6:00 A.M. both going up and coming home.

Mapping Hacks
Mapping Hacks: Tips & Tools for Electronic Cartography
ISBN: 0596007035
EAN: 2147483647
Year: 2004
Pages: 172
Simiral book on Amazon

Flylib.com © 2008-2017.
If you may any questions please contact us: flylib@qtcs.net