Author Archives: leigh
Welcome to Step Six in our exploration of open source GIS using Ubuntu. In the previous installments, we uploaded some spatial data into a PostGIS database, and experimented with spatial SQL. Finally, we’re ready to install QGIS, the most popular open source GIS desktop available. QGIS is a lot like ESRI’s ArcMap, in that it […]
Welcome to Step Five in our exploration of open source GIS using Ubuntu. In the previous installment, we uploaded some spatial data into a PostGIS. database. The next logical step is to install QGIS and add start visually analyzing this data, which we’ll get to in Step Six. But before that, I wanted to take […]
(Note – this post was updated on October 28 to include new information!) Welcome to Step Four in our exploration of open source GIS using Ubuntu. In the previous installment, we spatially extended our PostgreSQL database server with PostGIS. Now we’re ready to load some geographical data into our database. PostGIS includes a tool called […]
Welcome to Step Three in our exploration of open source GIS using Ubuntu. In order to grasp the full power of GIS, we need to spatially extend our database (PostgreSQL, which was installed in the first step). The spatial extension for PostgreSQL is PostGIS. In the second step, we installed GEOS and GDAL, two major […]
Welcome to Step Two in our exploration of open source GIS using Ubuntu. In order to grasp the full power of GIS, we need to spatially extend our database (PostgreSQL, which was installed in the previous step). The spatial extension for PostgreSQL is PostGIS, which we will eventually be installing. But before we can get […]
After a recent hard drive crash, I decided to try out Ubuntu, the most popular consumer Linux distribution. Ubuntu has become popular because it is more lenient than other distributions with regard to proprietary software – it can use Flash and play mp3s out of the box, without installing additional software. Ubuntu, like other Linux […]
A world file is a text file that is distributed with many raster datasets. It contains six lines of instructions which describe the location, scale, and rotation of the raster image. ArcGIS can read display information from the world file – but by default, it does not. Instead, ArcGIS prefers to read this information from […]
Contour maps have essentially gone out of fashion, replaced by shaded relief. There are still plenty of uses for contours, but they just don’t look as cool as a well-drawn hillshade. A colored hillshade is even more exciting. Traditionally, the easiest way to do that in ArcGIS was to place a color stretched DEM over […]
Unless you’re working on a hobby project, as a cartographer, you will eventually be expected to show your work. And sharing means making yourself vulnerable to criticism. That word itself, ‘criticism’, sometimes conjures images of personal attacks and low self esteem, but that’s not always the case. Often, a criticism can be extremely helpful, both […]
