Shallow Thoughts : : mapping

Finding the Bounding Box of a Dataset

Yesterday I wrote about PyTopo's difficulty in displaying a large all-US dam dataset. I've finally fixed the bug ... though it's still very slow to display the whole dataset: you have to wait a minute or more to redrew if it's zoomed all the way out to show the whole world.

Wait, the whole world? I thought this dataset was for all dams in the US?

Yes, in theory. In practice, not so much.

(I'm going to cheat a little bit and call this 30 Day Map Challenge Day 3: Polygons, because a bounding box is a polygon and I've spent so much time on this that I definitely don't have time to do any other 30 day projects today.)

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Plotting Dams (30 Day Map Challenge Day 1: Points) and a PyTopo Tweak

The 30 Day Map Challenge started yesterday, and already I'm a day behind. (I'm not going to try to keep up; I'll be sporadic about challenge entries.) Day 1 was Points.

The website for the challenge has an interesting list of possible data sources, and clicking around them, I found one that looked like a good quickie: a Data is Plural entry that mentioned a dataset from the National Inventory of Dams that lists all dams in the US. That sounds like a useful thing to have.

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PyTopo can Show GPS from Image Files Now (30DayMapChallenge #15, My Data)

For Day 15 of the 30 Day Map Challenge, "My Data", I'm highlighting a feature I added to PyTopo last week: the ability to read GPS tags in image files.

JPEG, and probably other image formats as well, lets you store GPS coordinates inside the EXIF (EXchangeable Image File format) metadata stored within each image file.

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An Old Autocross Course Map (30 Day Map Challenge #11: Pen and Paper)

I was going through some old paper files last year and discovered something I thought I'd lost: the event flyer and course map for the first autocross course I designed.

Autocross, or SCCA Solo II as it's technically called in the US, is car racing on a miniature course defined by orange traffic cones in a parking lot, airstrip or other available expanse of pavement. Lots of people autocross their street cars, but there are classes for everything up to highly modified open-wheel formula cars.

I got started autocrossing in Los Alamos in the late 80s, driving my Nissan 200SX turbo. In those days, there was an autocross club based in Los Alamos,

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Made it to LA Mountain, Finally

30 Day Map Challenge Day 5: A Journey

Last year for the #OpenStreetMap day of the 30 Day Map Challenge, I wrote about a hike that went a little wrong, when we lost our way on the Mitchell Trail and ended up going partway up the trail to LA Mountain.

LA Mountain is so named because Los Alamos High School kids have, for many years, maintained a big "LA" on the mountain that was visible from town. I say "was" because the LA is very hard to see now, and I've been told (but haven't been able to confirm) that's because the Forest Service, which owns the land, said the kids had to stop updating it. I'd seen it from below and always wondered how to get there, so last year, when I realized that was the trail we were on, I vowed to go back soon and go all the way up.

And then, of course, I promptly forgot all about it, until a few days ago when I was reviewing last year's 30 Day Map Challenge projects.

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Mapping to Protect Los Alamos Open Space (30 Day Map Challenge Day 3, Polygons)

How to Add Data from ArcGIS Web Maps to QGIS

Open Space advocates in Los Alamos county have been fighting the forces of development.

Ordinarily that's not a big problem. This county is wildly supportive of its open space; a huge percent of residents hike, bike, watch birds or otherwise appreciate the natural beauty around us. It helps that a lot of the town is on finger mesas adjacent to un-developable canyons, so you never need to go very far to be in a natural space.

But the county also loves to hire out-of-state consultants any time anything is changing, and a couple of years ago, they hired a consulting firm to rewrite Chapter 16 of our county code, concerning development. That included the zoning maps. The consultants capriciously changed several parcels previously zoned as open space to zones that allow much more development (like six-story apartment or commercial buildings), ignoring public input protesting the changes, and the County Council rubber-stamped the consultants' changes, promising to revisit the open space changes soon.

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Decoding Specialized FIT files (30 Day Map Challenge Day 2, Lines)

I have a new eBike! I'll write about it more before long, but for now, what's relevant to the 30 Day Map Challenge is that it's from Specialized, and if you use the Specialized phone app, it can record all sorts of fun statistics for rides, including GPS coordinates.

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30 Day Map Challenge Day 1, Points: Mapping New Mexico Peaks

November is the 30 Day Map Challenge.

Like last year, I'm going to work it sporadically, since I've been busy with a bunch of other things. But this sort of challenge can be a great way to motivate myself to learn new technologies or get better acquainted with old ones, so it's fun to work the challenges when I have time.

Day 1 is Points, and I'm mapping peaks in New Mexico.

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