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QGIS. Although I do most of my analysis using ESRI based tools, QGIS is extremely fast for quickly examining a shapefile, and zooming/panning/reading the attributes. I don't mean this in a derogatory way, as QGIS is also a wonderful open-source desktop GIS; but for quick file opening/closing it's wonderful and the quickest I've found.


Fiddler is excellent. Update Suppose I'm looking at a Web App, like Esri's Redistricting Online ... ... and I become curious about the mapservices it uses. I can fire up Fiddler and see what Urls it is accessing. I can right click and copy the url and paste into a web browser, since we're dealing with REST ... http://redistricting.esri.com/arcgis/rest/...


Benjamin already mentioned SAGA GIS, but just the name so I would like to add more info about this excellent SW: SAGA (System for Automated Geoscientific Analyses) SAGA is also free and opensource like QGIS, but it is focused on raster data analysis and processing. The standard modules are: File access: interfaces to various table, vector, image and grid ...


GIMP and INKSCAPE I use these two for cartographic purposes. Gimp has good raster support (until they get huge/GB in size, then you run it on a linux OS!) and Inkscape handles vectors really well.


JTS Topology Suite, particularly JTS TestBuider (for Windows users, make a Shortcut to C:\Program Files\JTS\jts-1.11\bin\testbuilder.bat). With JTS TestBuilder, you can copy/paste WKT or WKB into the geometry inputs, and debug a geometry (especially if it is invalid and you want to know why) or explore spatial functions and spatial predicate operators, etc. ...


Firebug for Firefox Inspect HTML and modify style and layout in real-time . Use the most advanced JavaScript debugger available for any browser. Accurately analyze network usage and performance. Extend Firebug and add features to make Firebug even more powerful. http://getfirebug.com/ Like it as you can edit webpages online and see the changes ...


For statistical analysis, there is R. An integration of R with ArcGIS provides the Geospatial Modelling Environment. Using the right libraries you can easily handle shapefiles and raster data in R RStudio is a powerful IDE with debugging and improved data handling for R.


Color Oracle - a colorblindness simulator for Window, Mac and Linux. I use this for checking the "look" of my composed maps.


Eclipse and PyDev for Python coding - the latest version (finally) allows you to run a script without it being in the project, and has some other great features as well (break on exception etc.). That and the almost unlimited other number of extensions that you can install in Eclipse. Git for version control. Free, easy, and you don't need to install any ...


There are lots of free GIS tools available. One of the imho best is QuantumGIS: http://www.qgis.org. It is available for win/mac and linux. But maybe you prefer openjump a tool written in java, which has special strengths in editing, topology-checking: http://www.openjump.org/ Also take a look at: http://freegis.org/


The Gdal command line tools are quite useful. ogrinfo myshapefile.shp gdalinfo myrasterfile.tif ogr2ogr to convert files. Sometimes I also use the xpath tool (provided with the gnome libxml2 library) to inspect xml/xsd/kml files: cat my-insanely-complex-xml-file.xml | xpath "//Placename/text()" You get the idea.


I wonder why MAPNIK has not been mentioned yet. It is also pluged in to QGIS. Very nice tool for easily making astonishing looking maps.


Irfanview - for making simple image edits, such as cropping screenshots. Much more useful than MS Paint, and batch image processing! Free JavaScript Editor - for editing JS, but also CSS, HTML, etc. Contains some great error checking functions, including a direct link to JSLint Firebug - priceless when debugging a web application in FireFox PythonWin - ...


FugroViewer - Fantastic program for viewing LIDAR data saved in LAS files. It has 2D, 3D and profile view. You can symbolize dots with all attributes stored in LAS files along with RGB colors.


Update: Boundless no longer has a Community Edition of the OpenGeo Suite. It simply offers a download at : http://boundlessgeo.com/solutions/opengeo-suite/download/. They now have an Enterprise Edition which provides support and other features/tools (e.g Composer) According to their twitter account: You can do anything [with the download] you could have ...


For converting to las 1.2 from las 1.4, PDAL's translate command is an option: pdal translate --writers.las.minor_version=2 input-las14.las output-las12.las LAStools can also do the job: las2las -i input-las14.las -set_version 1.2 -o output-las12.las In general, las 1.4 support is patchy among free and open-source las-aware software, e.g. liblas doesn't ...


Self-link, but TileMill is very useful for exploring geodata, making pretty maps, doing analysis, etc. It's mainly for the presentation and exploration steps, while the heavy-lifting of analysis can be done in QGIS or similar.


Notepad++ as well as the extra settings from TWIAV.nl especially the code highlighting. Came in very handy after changing server structures as all our .wor files were broken. One short find and replace later and everything works!


You might want to try Orfeo Toolbox. OTB is based on the medical image processing library ITK and offers particular functionalities for remote sensing image processing in general and for high spatial resolution images in particular. Targeted algorithms for high resolution optical images (SPOT, Quickbird, Worldview, Landsat, Ikonos), hyperspectral ...


GDAL supports .img format, both the basic Imagine and the extended Imagine (greater than 2GB), thus any software that utilizes GDAL drivers would support ERDAS Imagine. The most workable and well documented that I have seen is QGIS. It is also open source and therefore free.


A great GIS that has a huge amount of functionality is QGIS. It is very easy to install especially if you use the osgeo4w installer (Windows). You can use it to view your GML file too. OSGeo is the place you want to look for OpenSource (free) GIS tools and libraries: http://www.osgeo.org/. You will find a ton of stuff here plus links to QGIS and other ...


Maybe these links will help you: How to build effective heat-maps? with QGIS: http://alexsciuto.com/blog/2010/11/how-to-make-your-own-heat-map-pt-1-gathering-the-materials/ Python script: http://www.sethoscope.net/heatmap/ http://sk53-osm.blogspot.com/2011/01/heat-maps-from-osm-pois.html Sorry for a non elaborated answer..


Here a generic soluion, that you can impĺement with PostGIS or any other OGC-compliant software. NOTE: as I say before, a key concept in FOSS and GIS is standardization: the best solutions adopt standards, like OGC ones. Your problem is to "find pseudo nodes"... But I think that it is a little more, "find non-pseudo nodes and join lines of pseudo nodes". ...


While Esri does have some freely available tools, the ArcObjects SDK (.NET or Java) is not one of them. ArcObjects is a licensed product, available from the same distribution mechanism as the rest of the ArcGIS platform. In general, the procedure for gaining access to Esri software is: Contact an Esri representative (via web site, US regional office or ...


There are two programs using the libgeotiff library that will let you export and import georeferencing info from GeoTIFFs (and other image file formats): listgeo for saving the georeferencing info into a file, and geotifcp for writing the info from that file back to the image file after it's been edited. Downloads for the libgeotiff library can be found here:...


Nobody mentioned about proj.4 Proj.4 is an open source cartograpic projection library and tool that works hidden in the most of desktop gis, spatial databases and gis service software (web stuff). You can use it also very effictive at the command line and beside of geotrans (which has military roots) it is IMO the open source tool to transform cooordinates ...

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