Saturday, March 1, 2008

ArcIMS Servers seem to rule

I spent this week working alongside an intern who came down from the University of Michigan to help Dan with a flash presentation... a quick thanks to her for playing DJ all week... heard some fantastic new music!

From a tech standpoint, I was able to make a lot of progress with the interface, hooking up the remaining layers. I took the program to Loyola yesterday to demo it for my good friend, David Goldblatt, a GIS guru with Loyola's Center For Urban and Environmental Policy group, and he gave me a ton of constructive feedback.

He then introduced me to the magic of ArcIMS servers.

In my ArcGIS training, I learned to surf the web and "steal" premade shapefiles (map layers) if I needed them. If a layer was unavailable (for instance, it's hard to find premade shapefiles for IL schools that are up to date), you have to find address data and run a process called "geocoding" whereby the software tries to match the address to its database of known streets. This is problematic for two reasons (off the top of my head). First, there are new streets and subdivisions built daily... so often the software's street data can't find a match. When this happens, you have to manually match the address to a nearby street that DOES exist in the database. This takes a lot of time. Especially if there are thousands of unmatched schools. And of course, it's inaccurate. Second, schools open and (too frequently around here) close. In the shapefile I have for instance, Al Raby High School is listed as Lucy Flower Vocational. Same building... new name... old data.

So periodically my search for geocodable address data ends up at a place like this school locator. Cool toy, but how do I get to the data behind the site? Until yesterday I thought I couldn't. Turns out, Arc Catalog allows you to link to some sites' data layers using "ArcIMS Servers"!

Why did no one tell me this before? :) Now I have access to all kinds of school data, crime data from the police, transportation data ... on and on. They warehouse the data... so they maintain and update the data too. What's more, their symbols are customized and professional-looking. This almost seems too good to be true, but for now, this is going to save my uncountable headaches (until I discover limitations!)

So that is my big discovery this week. Maybe you didn't know about this either. Maybe you have more ArcGIS tips to share with me.

And I should mention that my understanding of ArcObjects continues to improve. If anyone needs help/code, maybe I can be of assistance.

Have a great week!

1 comment:

~Sarah~ said...

I couldn't help but notice that while wandering on the web looking for mention of your school I stumbled across your reference to Al Raby High School and ArcGIS....because I'm the GIS teacher at Al Raby! :) We use the ArcMap software to look at community and environmental issues around Chicago. Possibly we can share data! Anyways, just had to share a comment!

~Sarah Giddings