artlemboSep 18, 20191 minVirtual layers with QGIS – wait a second, this is starting to look like Manifold…If you are like me, you love writing spatial SQL. But what can you do if you have a geodatabase, some shapefiles, or any other data format? Well, you can a...
artlemboMar 14, 20193 minEasy bivariate map with PostgresA friend recently asked me about the cool looking bivariate maps produced with ArcOnline, lamenting that the capability seemed lacking in ArcGIS. Well, it ...
artlemboFeb 21, 20192 minEngaging students with multiuser editing, and FOSS4gA friend is doing some research on estrogen and estrodial in water samples in Delaware. We have about 50 sub-watersheds that show the upstream contributin...
artlemboOct 16, 20185 minBig Data ResultsI wanted to revisit the taxi data example that I previously blogged about. I had a 6GB file of 16 million taxi pickup locations and 260 taxi zones. I wante...
artlemboJul 7, 20182 minFinding “Dangles” with PostGISDo you have a set of lines that you need to determine if there are any “dangle” nodes? A dangle is a line segment that overhangs another line segment. Now,...
artlemboJun 22, 20181 minMulti-Ring (non-overlapping) Buffers with PostGISI was interested in creating mult-ring buffers but with a twist: I didn’t want the buffers to overlap one another. In other words, if I had concentric buffe...
artlemboMay 17, 20171 minCartography in ArcGIS and QGISShe also has an innate ability to work with GIS, and pick up new things: one day she has never programmed in Python, and the next day, she has a couple of hu...
artlemboMay 3, 20174 minThe Web Duel – Last ThoughtsThe Web GIS Duel: Final Thoughts This is a continuation of Mark Balwanz’s blog posts on his creation of web mapping sites using both ESRI and Geoserver. Tod...
artlemboJan 27, 20172 minWorkshops at the Maryland Geospatial Conference#TUgis2017) is on March 20/21, 2017. I first attended TUgis in 1990, and it is always a great conference. It is not too large, so it is great way to have ...
artlemboOct 25, 20162 minA Typical Class Project at Salisbury University: Evaluating Geocoding AccuraciesI’ve always been proud of our Salisbury University GIS students, and love to push them as far as their little minds can handle it. You may recall that last ...
artlemboJul 23, 20162 minQGIS GPU Processing UpdateToday my students got to present some of their work at the Maryland Geographic Information Committee Quarterly meeting. On Monday we head to the University ...
artlemboJun 29, 20162 minParallel Processing with QGISOnce again, I am continuing my role as a mentor in a National Science Foundation (NSF) Research Experience for Undergraduate program. This year we’ve decide...
artlemboMay 26, 20162 minAdvanced Editing Capabilities with PostGISCLICK TO VIEW Jeff Scarmazzi presenting on h0w to create editing rules and triggers using Postgres and PostGIS Today I want to introduce you to another one o...
artlemboMay 22, 20166 minThe Web Duel: part 3, Open SourceThe Open Source Implementation This is a continuation of Mark Balwanz’s blog posts on his creation of web mapping sites using both ESRI and Geoserver. Today...
artlemboMay 18, 20163 minOpen Source GIS Course at UMD – the SyllabusUMD provided me with enrollment numbers, and we are getting a pretty full class. However, a few people on the “outside” have asked for a little more depth i...
artlemboMay 3, 20161 minUpcoming course: GDALI am putting up a new course on udemy.com about learning GDAL – and, it is going to be FREE. I’ve been so happy with the uptake and positive responses by so...
artlemboApr 19, 20162 minSQL and ogr to create 4D linesA friend recently asked me to help him generate polyline shapefiles with Z and M values that he could deliver to a customer. The problem was, the software h...