Can someone give me a list of free and open source GIS desktop packages?
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http://freegis.org/ - the oldest and perhaps most comprehensive directory of free GIS software and projects.
Wikipedia has most of them listed
- If you consider Google Earth as a GIS application, Nasa's WorldWind is an open source alternative.
- Epi-map, part of CDC's Epi-info epidemiology package, may be worth a look if you're in that line of work.
- OpenMap's free too. UI's pretty old school though. I prefer qGIS or uDig.
- QGIS supports native SAGA grid format so it is very easy to work with these two programs together and use advantages of both
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Portable GIS is a very useful set of Open GIS Tools that can fit on a USB stick and used on other computers and very good for field work on a laptop. Great for beginners or students without the resources to purchase for commercial GIS products.
Newly updated version 2 contains a self-contained installer, updated versions of all the constituent software packages, a new control panel, and improved documentation.
"this idea was to provide beginners with a ready-installed and configured stack of open source GIS tools that would run in windows without the need for emulation or a live cd. "
The current set of software includes:
* Desktop GIS packages QGIS (with GRASS plugin), uDIG and gvSIG, * FWTools (GDAL and OGR toolkit) * XAMPPlite (Apache2/MySQL5/Php5), * PostgreSQL (version 8.4)/Postgis (version 1.4), * Mapserver, OpenLayers, Tilecache, Featureserver, and Geoserver web applications.
(450MB download, and needs a USB stick of 2GB)
credit to Joanne Cook (archaeogeek) http://www.archaeogeek.com/blog/portable-gis/
Archaeogeek migrated to Octopress 02Apr12 Portable GIS v2 updated link http://www.archaeogeek.com/portable-gis.html
SAGA GIS, System for Automated Geoscientic Analysis, is often under represented in floss GIS lists. SAGA developed from raster processing roots, and is thus very strong there, and grew into vector handling and analysis later. It is a mature tool.
I'd recommend Whitebox GAT (http://www.uoguelph.ca/~hydrogeo/Whitebox/), although I'm a little biased, being the developer. It's free, open source, and transparent. It has powerful analytical capabilities for raster and vector data analysis and a friendly user interface.
The programming language R is focused on statistics, but has some good mapping capabilities. I wouldn't use it to design a poster-sized map, but it has several packages for handling GIS tasks. The best part is that you can crank out spatial statistics without needing to leave the program.
Admitted not the simplest one to learn, but nobody (except one in a list-answer) citing GRASS ?
I like its very simplicity when commands are given as simple bash scripts.. and I like to use bash scripts in order to keep track of what I do.. (and GRASS even does it automatically if you still want to use the GUI, as it keeps the log of the commands in a history file)
VTP the Vitrual Terrain Project, a 3D terrain visualization toolset which predates Google Earth, not a GIS in the strictest sense but the developers have GIS smarts so it leaks over a bit. It's intelligent about projections for instance.
I have used a free and open source program called ILWIS which I used to create a bushfire hazard map from slope, aspect etc.
Here are two good academic papers discussing these issues exactly. They deal mainly in biology, but compare the different packages very well:
As the previous answers have shown, there are a lot of candidates to choose from. The question should thus be "what OpenSource GIS fits my needs?" I wrote a paper with the title "Use of Free and Open Source GIS in Commercial Firms" in 2008, the framework I presented there should still be relevant. See: http://code.atlefren.net/download/dl.php?id=10
And then you have this wiki: http://sourceforge.net/userapps/mediawiki/mentaer/index.php?title=FOSS4G_Software_List which seems rather comprehensable.