
Laura,
 
As far as i know RGDAL and maybe proj4 will help you with geotiff, but it may be tricky if you want to preserve the geotiff projection. Your safest bet is to use a GIS software and ESRI ArcGIS can do everything you want without using R. To calculate differences, mean, and so on is a simple task in ArcGIS, no need for R. Evem more advanced statistics can be done in ArcGIS in their "expanded" calculator. You also can do some geostatistics, analysis of variances, correlations, "hot spots" and local outliers.
 
I hope this helps,
 
Monica
 
------------------------------ Message: 110Date: Wed, 14 Nov 2007 09:22:52 +0100From: "Laura Poggio" <laura.poggio@gmail.com>Subject: [R] geotiff calculationsTo: r-help@r-project.orgMessage-ID:<e027b8750711140022i17f77522vb70a213cbc05760b@mail.gmail.com>Content-Type: text/plain Dear list,I have to compare two digital elevation models in raster format (geotiff).I then have to calculate the differences in altitude for each cell and makesome statistics (basic as mean, median, std, range but also more "advanced"as RMSE) on that.I do not know very much how to proceed:1) is it possible to import the geotiff in R? If so with which package? ifnot which is the best way to import such files?2) is it better to perform the calculations of the differences in a GISsoftware and then to use R only for statistical analysis? or it is better todo everything in R?3) is there any specific package for doing this kind of analysis? Thank you very much in advance Laura [[alternative HTML version deleted]]   ------------------------------
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