Carving Up GIS StackExchange

So the data server that I was working with was having issues and, while waiting for the IT staff to resolve things, I decided to browse the GIS StackExchange site. It’s been online for quite sometime now, though I am only an occasional user. One thing led to another and I found myself playing with the StackExchange API, which returns various information for a particular site in a JSON format.

One of the things that got people excited about the site was that it was neutral territory, not directly controlled by a particular vendor or organization and it remains one of the few places where you can see hyperbole-free discussion of Esri tools right next to that of open-source tools and general GIS concepts. Since it’s been online for a while now, it has a lot of posts covering many different topics. I had some time on my hands, so I decided to pull the information for the 100 most “popular” tags, using the StackExchange API. With JSON in hand, I parsed into a CSV with Python and loaded the data into Excel to take a look. Continue reading “Carving Up GIS StackExchange”

Mapping GISPs Again With Leaflet.markercluster

So I’ve been playing with Leaflet a lot lately. It’s become my lightweight mapping library of choice. There’s a lot it doesn’t do so I keep OpenLayers and others in the rotation as well but Leaflet is direct and to the point so I use it when I can.

Click the image to go to the live demo

A while back, I stumbled onto the Leaflet.markercluster project on GitHub, which adds a clustering layer type. I wanted to try it so I revisited my old GISP heat map demo (Silverlight) and decided to rework it. I was happy to finally get a chance to strip out the plug-in, anyway. Continue reading “Mapping GISPs Again With Leaflet.markercluster”

Mowers and Maps

I was mowing the lawn today and trimming with the push mower pictured below. If it looks old, that’s because it is. I first acquired it in 1978 when it was given to me by neighbors that were moving to an apartment near the city, meaning they no longer needed it. It still starts on the third pull and I’ve used it every summer since it was given to me.

As I was mowing, I thought about how old the mower is and how it came to be in my possession. This led me to think about the origin of my fascination with maps. What does one have to do with the other? Allow me to explain.

As you can imagine, I was fairly young when the lawn mower was given to me. I had gotten to know the neighbors up the street by playing with their son. One day, I noticed a large shelf of identical, leather-bound books taking up the entire back wall of a room. I asked what they were and they invited me to browse them. It turned out that my neighbor was the son of a long-time chair of the National Geographic Society. These books were actually bound collections, by year, of every issue of National Geographic from the first issue on.

Over time, I would spend hours poring through these volumes, fascinated by the world as it was documented by National Geographic from 1888 forward. I did not get to read every issue but I was especially drawn to the maps when they were present. I realize now that my identity as a “map nerd” took root there.

Coincidentally, 1978 was the year I first started programming. Those two experiences turned out to be major influences on who I became.

Favorite QGIS Resources of the Moment

I’ve been dabbling more with Quantum GIS (QGIS) lately. I’m not doing anything particularly sophisticated but it’s a great viewer for some data types (SpatiaLite, GeoJSON) that aren’t supported by my commercial desktop GIS so it’s helping me validate outputs of some applications I’m writing.

While I’ll never be a real cartographer, I am interested in doing a little more. Here are the resources that have been helping me the most lately…
Continue reading “Favorite QGIS Resources of the Moment”

Using GeoIQ Analytics in .Net Applications

A few weeks ago, I posted about some .Net wrappers I created for the GeoIQ API. Due to ongoing project work, I have continued to extend them by adding methods to wrap GeoIQ analytical capabilities. Despite the recent acquistion of GeoIQ by Esri, it’s my understanding that GeoCommons and existing GeoIQ installations will continue for some time. That’s good, because analytics on the GeoIQ platform are powerful and fairly easy to use. This post will demonstrate how to use analytics in a .Net application.

As previously posted, the .Net wrappers can be found on github here.

The GeoIQ platform offers several functions to analyze data sets hosted on a GeoIQ instance or GeoCommons. I have not yet wrapped all of the functions but am working my way through them as I can.

For this post, I will intersect the locations of US GISPs as of 1/26/2011 with the Maryland Zip Code Boundaries to produce a data set containing the locations of GISPs in Maryland, depicted in the map below.

Don’t worry, none of these are me.

Continue reading “Using GeoIQ Analytics in .Net Applications”

GeoIQ & Esri

Okay, everybody calm the hell down. Anyone who thinks that the Esri acquisition of GeoIQ is strange hasn’t been paying attention to two things: 1) the direction that Esri says they want to go and 2) what the GeoIQ platform really is. I would be very surprised if GeoIQ becomes the 2012 version of Atlas GIS. This acquisition/merger makes more sense than may be initially apparent.


It’s no secret that I’ve worked with Esri tools for a long time and my recent work with the GeoIQ platform has been well-documented on this blog, including work integrating the two platforms at the API level. Based on what I’ve seen from both companies, here are thoughts on why I think this move makes a lot of sense: Continue reading “GeoIQ & Esri”

CartoDB/Leaflet Sample Update

A while back, I posted about some experimentation I did with Leaflet and CartoDB in the wake of FOSS4G in Denver. I recently had the chance to go back and update that sample with some spatial queries. At the time of the original post, CartoDB was still in beta and spatial queries didn’t seem to work, despite the fact that the back-end was driven by PostGIS.

Continue reading “CartoDB/Leaflet Sample Update”