Hmm... it has been a while

It has been far too long since I've actively driven this project. As such, I'm seeking ways to share the source code I've generated. I'm exploring Google Code and will report back once that is good a setup.

Thanks for staying tuned and I hope opening up the code will spark new life into the work.

A bit of a break...

I apologize for not updating the blog for the last week - I've been silent because I have just started a new job and haven't had the time to come back to the work here yet. I do plan to come back to it, however at a slower pace. In the mean time, do not hesitate to reach out for help with similar efforts by either using the comment system or dropping me an e-mail at censuskml at gmail.

Fixed KMZ Downloads

An alert reader pointed out that the KMZs I posted yesterday were not properly downloading as KMZ files - the ended up as ZIP files on the desktop. This was because I was using Amazon's S3 service to host the files which apparently doesn't have the KMZ mime type set. I've moved the KMZs to BingoDisk which fixes the problem in my testing. Please let me know if you have difficulty getting these new files.

As a side note, the Google Maps links don't work with the BingoDisk files, but do with S3, so I've left a copy there as well.

Change your feed readers!

Good morning! For those of you that enjoy getting updates via the feed, I kindly request that you change your readers to use my new feed:

http://feeds.feedburner.com/CensusKmlDataVisualization

Blogger is good at many things, but getting a sense of how your feed is used is not one of them. Thank you!

Blogger ate my post on new features/code improvements

Today's 500 word post was just eaten by the Blogger spell-checker. I'm going to attempt to retrieve it, but it isn't looking good. The topic of the post was some major improvements I've made to the code base that make it much more generic and support two new features:

• Exclusions are now handled - if a polygon has an exclusion listed in the Census shape file, this is now handled. This turns out to be quite important for some areas. I'm working on a map of Washington state at the Block Group level and it turns out that in the rural parts of the state there are a couple of small towns that have a single Block Group surrounding the town and then separate, smaller Block Groups for the town itself. Before, these smaller Block Groups might have been covered up.


• A geography made up of multiple polygons now acts as one object in the KMZ output file.

In addition, I've made a number of enhancements under the hood. While I had been using some object-orientation before, I finally made the classes much more complete and generic so that it is much easier to add new geographies. For example, I created the Polygon object which encapsulates all of the information for a given polygon in one container:

class Polygon
  attr_reader :id, :centerLon, :centerLat, :mainCoords, :exCoords
  attr_writer :id, :centerLon, :centerLat
  
  def initialize(id, centerLon, centerLat)
    @id = id
    @centerLon = centerLon
    @centerLat = centerLat
    @mainCoords = Array.new()
    @exCoords = Array.new()
  end
end


With these improvements, I hope to have some maps to share soon. When I am once again inspired, I will share a lot more detail about the process and recent improvements.

I haven't disappeared...

I apologize for the lack of posts last week. I spent the week on vacation and didn't dream of touching a computer. My trip spurred a bunch of ideas for interesting maps that I am already working on. In the mean time, I will share a quick panorama I put together from pictures overlooking Hana, on the eastern side of Maui.

New way to reach CensusKML

To further facilitate the conversation about mapping Census data in Google Earth, I've created an e-mail address: censuskml [at] [gmail] (I hope you can decipher it). Feel free to reach out to me with specific questions or inquiries using either the e-mail address or the comment system.

KML (& KMZ) Support Added to the Google Maps API

Google Maps API Official Blog: KML and GeoRSS Support Added to the Google Maps API - this is pretty interesting since the functionality has been available in Google maps for some time [see my previous post]. The post doesn't explicitly state it, but I KMZs seem to work just as well. There appears to be some size limit to between 100 - 200 kb, from simply experimentation. Just to share again, here are two KMZs of population by County Subdivision from the 2000 Census that you can view on Google Maps:

• Massachusetts
• Wyoming

Welcome to Census KML!

A couple of days ago my wife asked me to help her map some Census data. I have always been interested in maps, and after a couple of web searches, I found a couple of interesting examples of people using Google Earth to map data. In particular, I found this post on the Juice Analytics blog. This got me going - I had some spare time, a desire to learn Ruby, a lot of data, a love of data visualization, and a purpose.

I plan to use this blog to share what I've created and let others share their knowledge, feedback, and experience. Please join in the discussion and check back frequently as I hope to share what I've found.

This wouldn't be much of a start if I didn't share some of the progress I've been making. The following screen shot shows the 2000 Census population by County Subdivision data where each meter of height represents 10 people. [There is also coloring, but I've found what appears to be a bug in Google Earth such that it doesn't properly draw colors for 3D polygons.]