Last update:
Wed Jan 8 21:00:32 2025
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This site aims to bring out some of the latest and sometimes not-so-greatest happenings in the GIS world. We’ll focus to large extent on Open Source software but hopefully mix it up to keep things interesting. We’ll explore things from the new and exciting to the dull and mundane. There are a lot of GIS/Spatial sites out there. Hopefully we can provide some content of interest and you will add this one to those you visit frequently.
Marco Hugentobler at the Institute of Cartography, ETH Zurich has announced the QGIS MapServer project. From the website: “QGIS mapserver is a server module for geographic maps. The content of vector and raster datasources (e.g. shapefiles, gml, postgis, wfs, geotiff ) is visualized according to the request parameters. The generated map image is sent back to the client over the internet.“ This project is very much in the early stages, as it requires a specific development version of QGIS.
Here is a short list of resources available when writing Python code in QGIS. If you know of others, please leave a comment. Blogs/Websites In alphabetical order: GIS StackExchange Kartoza Linfiniti Lutra Consulting Nathan Woodrow Nyall Dawson Twitter #pyqgis Documentation Choose the version to match your QGIS install PyQGIS Cookbook QGIS API Example Code Existing plugins can be a great learning tool Code Snippets in the PyQGIS Cookbook Plugins/Tools Script Runner: Run scripts to automate QGIS tasks Plugin Builder: Create a starter plugin that you can customize to complete your own plugin Plugin Reloader: Allows you to reload a plugin from within QGIS pb_tool: Tool to compile and deploy your plugins Books PyQGIS Programmers Guide Geospatial Desktop: GIS Scripting (PDF)
This week we take a look at a how to plot a terrain profile using the Profile plugin. The plugin can be used with any raster format supported by QGIS. You can can display profiles from up to three rasters at once, allowing you to compare the results. To illustrate, we’ll create a simple profile using a DEM of a 1:63,360 quadrangle in Alaska. Installing the Plugin The Profile plugin is installed like all other Python plugins.
The Pragmatic Programmers have announced the upcoming Desktop GIS title.
Everybody who gets an Eee PC has to write about it–it’s required. I don’t really have much to add to the raft of reviews, except for one small point. I found myself wanting to print something and, based on my last experience, prepared for the ordeal of setting up a printer. I about fell out of the chair when I opened the Printer configuration and found that the Eee had already found the CUPS printer on my network and added it.
Lets face it, GIS systems are complicated. Typically there are multiple servers and applications that make up a “system”. Each of these represent a potential point of failure, thus creating a brittle system. Brittle systems break. The definition of the word brittle is: Brittle: Solid, but liable to break or shatter In other words, we can design solid systems that serve us well, but they can be brittle. We can push on them a bit and they perform well, but push too hard and the whole thing shatters.
I keep seeing more evidence that many people and organizations are migrating to open source GIS on the desktop. In many cases a mix of proprietary and open source GIS is in use. I’m wondering about other’s experiences in this area. To gain some insight, I’ve created a poll (right margin). Please take a second and vote.
The book is now available in beta. Excerpts from two of the chapters are available online. What’s a beta book? Well in this case it’s a lot like software—feature complete and ready for you to give it a spin. The announcement from the Pragmatic Bookshelf: The Pragmatic Bookshelf | Desktop GIS “From Google Maps to iPhone apps, geographic data and visualization is quickly becoming a standard part of life. Desktop GIS shows you how to assemble and use an Open Source GIS toolkit.
$ uptime 20:20:56 up 434 days, 15:31, 2 users, load average: 2.32, 0.89, 0.53
We’re planning a couple of training classes for March: Introduction to QGIS Extending QGIS with Python Each is a one day class and we plan to run them back to back. If you are local or just want to come to Alaska in March for some spring skiing, northern lights viewing, or to experience the equinox, please hop over to GeoApt and let us know so we can plan accordingly.
The QGIS project has a number of support channels. Like many open source projects, these are loosely coupled. Recently the forum was made read-only and this has prompted a number of questions and concerns about how to receive support. This post outlines the ways in which you can get your questions answered. Home Page The QGIS home page has links to all the documentation and community resources. The navigation panel on the left has links to both the Community resources and the manual.
The QGIS Python console is great for doing one-off tasks or experimenting with the API. Sometimes you might want to automate a task using a script, and do it without writing a full blown plugin. Currently QGIS does not have a way to load an arbitrary Python script and run it.[1] Until it does, this post illustrates a way you can create a script and run it from the console.
The forum (http://forum.qgis.org) has been closed for new registrations and marked read-only. Users have been encouraged to use http://gis.stackexchange.com instead. If you have an thoughts on the closure, good, bad, or otherwise, please comment.
The PyQGIS Programmer’s Guide is now available in both paperback and PDF. A sample chapter is also available for download. The book is fully compatible with the QGIS 2.x series of releases. See locatepress.com for details.
This week we look at the OpenLayers plugin for QGIS. This plugin allows you to add a number of image services to your map canvas: Google Physical Streets Hybrid Satellite OpenStreetMap Yahoo Street Hybrid Satellite Bing Road Aerial Aerial with labels Installing the Plugin The OpenLayers plugin is installed like all other Python plugins. From the the Plugins menu in QGIS, choose Fetch Python Plugins.
Suppose you have a DBF (.dbf) file containing X and Y values that you want to import and save as a spatial layer. QGIS doesn’t support direct import of a DBF file as a map layer, however, we can use some command line magic to convert it to a CSV file and then use the Delimited Text plugin to get the job done. Your DBF file should have an id for each record and fields containing X and Y values.
$ uptime 20:20:56 up 434 days, 15:31, 2 users, load average: 2.32, 0.89, 0.53
An interesting visualization of QGIS development over the last eight years: http://woostuff.wordpress.com/2011/01/03/generating-a-gource-source-commit-history-visualization-for-qgis-quantum-gis/
Looks like the ink is dry on Desktop GIS and it should start shipping soon. You can get the full scoop from the Pragmatic Bookshelf. Update: It’s now shipping. See the announcement.
