[R-sig-Geo] shapefiles, images, iimagemaps, and removinginternalboundary lines

[Roger Bivand]

On Thu, 19 Oct 2006 matt.pettis at thomson.com wrote:

> Thanks! Got it to work.
> 
> However, the install of "imagemap" didn't work for me... I'm on Windows
> XP, and the souce comes in a .tar.gz file, which the 'Packages > Install
> packages(s) from local .zip files...' doesn't recognize.  Any alternate
> location for this, or a method for windows xp to import this module
> correctly?

The *.tar.gz is a source package. The *.zip are typically Windows binary 
packages, pre-built. Some Windows users with programming experience do 
build their own from source, the toolset is described in Appendix E of the 
R Installation and Administration manual, and package installation in Ch. 
6. If that isn't for you (or anybody nearby), say, and someone may have a 
go at building a Windows binary. Whether it is worth the trouble for 
spatial objects will however depend on the objects you want to make 
clickable, if they are simple, it'll work, but if they are polygons with 
very detailed boundaries (remember that the image map is raster while the 
boundaries are vector), it may not scale well. Probably worth trying, 
though.

Roger

> 
> Thanks,
> matt 
> 
> -----Original Message-----
> From: Roger Bivand [mailto:Roger.Bivand at nhh.no] 
> Sent: Thursday, October 19, 2006 11:14 AM
> To: Pettis, Matthew (TLR Corp)
> Cc: r-sig-geo at stat.math.ethz.ch
> Subject: RE: [R-sig-Geo] shapefiles, images, iimagemaps, and
> removinginternalboundary lines
> 
> On Thu, 19 Oct 2006 matt.pettis at thomson.com wrote:
> 
> > Hi Roger,
> > 
> > Thanks again for the response.  To answer your questions:
> > 
> > - I am currently running on R 2.3.1.  I was at 2.4.x, but some of the 
> > packages I thought I needed weren't available on the cran interface in
> 
> > the rgui (I was experimenting, and I can't remember what they were 
> > now, so that may no longer be true).  It sounds like you are fine 
> > running R at 2.4, though, and I could probably upgrade, as my sole 
> > purpose for having R right now is to deal with shapefiles and create
> image maps.
> > 
> > - Related to the above, I don't see the spgpc package on my mirror 
> > (USA (IA)), but that may be related to being at 2.3?
> 
> No, but it isn't on CRAN, only on the little sp extras repository on
> sourceforge:
> 
> rSpatial <- "http://r-spatial.sourceforge.net/R"
> install.packages("spgpc", repos=rSpatial)
> 
> so this should install it. In fact there isn't yet a Windows binary for
> 2.4, so 2.3 is OK.
> 
> > 
> > Also, I saw the 'unionSpatialPolygons' command in Debarchana Ghosh's 
> > code, but didn't know what it did.  I'll investigate the paths you 
> > have listed here.
> > 
> > Thanks again,
> > Matt
> > 
> > -----Original Message-----
> > From: Roger Bivand [mailto:Roger.Bivand at nhh.no]
> > Sent: Thursday, October 19, 2006 2:32 AM
> > To: Pettis, Matthew (TLR Corp)
> > Cc: r-sig-geo at stat.math.ethz.ch
> > Subject: Re: [R-sig-Geo] shapefiles, images, iimagemaps, and removing 
> > internalboundary lines
> > 
> > On Wed, 18 Oct 2006 matt.pettis at thomson.com wrote:
> > 
> > > I have sucessfully inputted a shapefile into a 
> > > SpatialPolygonsDataFrame object.  I would like to output this file 
> > > as a .gif/.png/.bmp/.jpeg image and generate an imagemap for the 
> > > outputted image.  Does anybody know the best way to approach this?
> > 
> > RSiteSearch("imagemap")
> > 
> > gets you to:
> > 
> > http://finzi.psych.upenn.edu/R/Rhelp02a/archive/28035.html
> > 
> > This installs on R 2.4.0 from source - which platform are you using 
> > and can you install source packages? The documentation in 
> > imagemap/inst/doc/imagemap-howto.pdf is clear, addRegion(im) <- for 
> > each clickable object. How to go from there depends on what you want 
> > to be clickable.
> > 
> > Alternatives might be Rpad:
> > 
> > http://finzi.psych.upenn.edu/R/Rhelp02a/archive/77952.html
> > 
> > or using ogr2ogr in FWTools (external software) to generate a KML for 
> > Google Earth (if the bubble that pops up is enough - I don't know how 
> > to put a link into it, though I guess it could be done), or writing 
> > the KML from R:
> > 
> > http://bbs.keyhole.com/ubb/showflat.php/Cat/0/Number/221682/Main/21913
> > 1
> > 
> > >  secondly (and i may need to start another thread for this), but is 
> > > there an easy function to remove the interior lines of aggregated 
> > > shapes (and generate an imagemap again, etc.)?  For example, If I 
> > > have
> > 
> > > a map of the U.S.'s with a polygon for each state, could I remove 
> > > all internal state boundaries to leave just the national border?
> > 
> > Using the objects you have now, you need to install the spgpc package:
> > 
> > rSpatial <- "http://r-spatial.sourceforge.net/R"
> > install.packages("spgpc", repos=rSpatial)
> > 
> > and install gpclib from CRAN. Then
> > 
> > ?unionSpatialPolygons
> > 
> > to dissolve internal boundaries. This is for arbitrary polygons, if 
> > you really just need to dissolve US states, perhaps using the CRAN 
> > maps package with its built-in database, and its own dissolve 
> > mechanism would save re-doing topology, but it only works for polygons
> in the database.
> > 
> > Roger
> > 
> > >  
> > > thanks,
> > > Matt
> > > 
> > > _______________________________________________
> > > R-sig-Geo mailing list
> > > R-sig-Geo at stat.math.ethz.ch
> > > https://stat.ethz.ch/mailman/listinfo/r-sig-geo
> > > 
> > 
> > --
> > Roger Bivand
> > Economic Geography Section, Department of Economics, Norwegian School 
> > of Economics and Business Administration, Helleveien 30, N-5045 
> > Bergen, Norway. voice: +47 55 95 93 55; fax +47 55 95 95 43
> > e-mail: Roger.Bivand at nhh.no
> > 
> 
> --
> Roger Bivand
> Economic Geography Section, Department of Economics, Norwegian School of
> Economics and Business Administration, Helleveien 30, N-5045 Bergen,
> Norway. voice: +47 55 95 93 55; fax +47 55 95 95 43
> e-mail: Roger.Bivand at nhh.no
> 
> 

-- 
Roger Bivand
Economic Geography Section, Department of Economics, Norwegian School of
Economics and Business Administration, Helleveien 30, N-5045 Bergen,
Norway. voice: +47 55 95 93 55; fax +47 55 95 95 43
e-mail: Roger.Bivand at nhh.no