On Saturday 24 November 2007 08:31:33 pm tom sgouros wrote: > Thanks very much for the reply. I think a lot of my confusion is in not > knowing where the boundaries fall between the different applications. > Can you tell me roughly the division of labor among the software you > mentioned?
Sure. I use GRASS / PostGIS anytime I need to work with GIS data: raster, vector + attributes, etc. Importing, merging, subsetting, modification, and summarizing are best done within a GIS (I think). When I need graphical summaries (box and whisker plots and such) I will import the data into R and go from there. In other words, most of the heavy lifting of pushing pixels and vertices is done in the GIS. All of the analysis is done in R: summaries, hypothesis testing, and prediction using models. This nice thing about the GRASS-R bindings is that you can predict from GRASS data, and send the predicted values right back into a GRASS raster/vector . Lately I have been using R to produce some maps -- although mainly maps of purely vector data like thematic maps. The high quality PDF output from R makes for an ideal platform for producing press-ready vector graphics. Check out the spplot() function in the sp package for plotting a mixture of vector / raster data. When plotting raster data out to a PDF, be careful about generating gigantic files -- each pixel can be represented with a little rectangle, and for large grids can result in massive PDF files. I will try and post an examples of this.. in the mean time check out Roger's sp website- it should be in the manual page for the sp package. There are numerous mapping examples in there. For more complex maps I tend to favor GMT. Examples: http://casoilresource.lawr.ucdavis.edu/drupal/node/130 > > Dylan Beaudette <[EMAIL PROTECTED]> wrote: > > For most of my work GRASS, > > GMT, PostGIS, R, and Mapserver are a tough combination to beat. > > Do you know any identifying details about the books you speak of here? > (Are you writing one?) I had to look through some notes: i am reviewing one of them, and contributed a chapter (along with Markus Neteler and others) to the other. 1. Desktop GIS by Gary E. Sherman This one provides an excellent introduction to both GIS and the entire range of open source software which can be used. There isn't (as of now) anything in there about R, but is a great resource otherwise. 2. G.B. Hall (Ed), "Open Source Approaches to Spatial Data Handling", Springer, New York. In press. This one should have some material on R -- sprinkled into some of the relevant chapters. I know that the GRASS chapter has a bit on R, specifically that kriging example I sent last time. A Related example can be found here: http://casoilresource.lawr.ucdavis.edu/drupal/node/442 Those books should be out soon- I will post back when I hear from the authors / publisher. > > See above suggestions. There should be two books out soon which are > > dedicated to opensource GIS applications- I would keep an eye out for > > these. > > Thanks again, > > -Tom Cheers, Dylan _______________________________________________ R-sig-Geo mailing list R-sig-Geo@stat.math.ethz.ch https://stat.ethz.ch/mailman/listinfo/r-sig-geo