Re: [R] Select.spatial on spplots
Charlie's reply is quite correct - without an example that others can reproduce, it is hard to offer help. Julius is also ignoring the fact that spplot() methods use lattice graphics, while select.spatial() uses base graphics. The spplot() method for SpatialPointsDataFrames objects does provide an identify= argument, but this is not the same as select.spatial(), which lets the user select points spatially by drawing a polygon around the ones to be selected. Roger Bivand cls59 wrote: Julius Tesoro wrote: Hi everyone. I posted this on R-sig-geo but got no response. Can select.spatial() be used in an existing spplot? I have tried selecting points (eq) from a plot generated from sp. However, when I invoke select.spatial(eq). It generates only the points without the background containing the faults. I need the background to select which earthquakes coalesce on which fault. Is there an alternative? eq.pts-list(sp.points,eq, col=blue, lwd=0.5, pch = 4) spplot(faults,Dip, xlim = c(11,12), ylim = c(376,389), sp.layout=list(eq.pts), col = heat.colors(3)) select.spatial(eq) Cheers, Julius Tesoro Unfortunately, it looks like select.spatial() wipes the plotting region by executing it's own call to plot(). However, the function it's self is very, very simple, just type: select.spatial To see what goes on inside. It looks like you could obtain point-wise selection by just calling identify(): identify( coordinates( eq )[,1], coordinates( eq )[,2] To use areas, call locator() and then process the results using point.in.polygon(). As for whether this will work using a spplot-- I really couldn't say. I was not able to reproduce a spplot using the information you provided-- lack of a working example may be a reason you got nothing but silence on R-sig-geo. Good luck! -Charlie -- View this message in context: http://www.nabble.com/Select.spatial-on-spplots-tp25632668p25652492.html Sent from the R help mailing list archive at Nabble.com. __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
[R] Select.spatial on spplots
Hi everyone. I posted this on R-sig-geo but got no response. Can select.spatial() be used in an existing spplot? I have tried selecting points (eq) from a plot generated from sp. However, when I invoke select.spatial(eq). It generates only the points without the background containing the faults. I need the background to select which earthquakes coalesce on which fault. Is there an alternative? eq.pts-list(sp.points,eq, col=blue, lwd=0.5, pch = 4) spplot(faults,Dip, xlim = c(11,12), ylim = c(376,389), sp.layout=list(eq.pts), col = heat.colors(3)) select.spatial(eq) Cheers, Julius Tesoro __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
Re: [R] Select.spatial on spplots
Julius Tesoro wrote: Hi everyone. I posted this on R-sig-geo but got no response. Can select.spatial() be used in an existing spplot? I have tried selecting points (eq) from a plot generated from sp. However, when I invoke select.spatial(eq). It generates only the points without the background containing the faults. I need the background to select which earthquakes coalesce on which fault. Is there an alternative? eq.pts-list(sp.points,eq, col=blue, lwd=0.5, pch = 4) spplot(faults,Dip, xlim = c(11,12), ylim = c(376,389), sp.layout=list(eq.pts), col = heat.colors(3)) select.spatial(eq) Cheers, Julius Tesoro Unfortunately, it looks like select.spatial() wipes the plotting region by executing it's own call to plot(). However, the function it's self is very, very simple, just type: select.spatial To see what goes on inside. It looks like you could obtain point-wise selection by just calling identify(): identify( coordinates( eq )[,1], coordinates( eq )[,2] To use areas, call locator() and then process the results using point.in.polygon(). As for whether this will work using a spplot-- I really couldn't say. I was not able to reproduce a spplot using the information you provided-- lack of a working example may be a reason you got nothing but silence on R-sig-geo. Good luck! -Charlie - Charlie Sharpsteen Undergraduate Environmental Resources Engineering Humboldt State University -- View this message in context: http://www.nabble.com/Select.spatial-on-spplots-tp25632668p25635166.html Sent from the R help mailing list archive at Nabble.com. __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
