I'll look into fixing this popular problem. Robert

On Tue, Nov 22, 2011 at 6:11 AM, Boris Leroy <leroy.boris@gmail.com> wrote:

> >> Hi all,
> >>
> >> I am trying to plot different rasters (same extent, different
> >> resolutions), with the same color scale.
> >>
> >> I have read the different threads aiming at specifying a single color
> >> scale for different rasters and the simplest one seem to specify
> >> zlim() when plotting.
> >> I tried with the example I found in the help page of plot {raster}.
> >>
> >> r <- raster(nrows=10, ncols=10)
> >> r <- setValues(r, 1:ncell(r))
> >> r[] <- runif(ncell(r))
> >> r2 <- r/2
> >> brks <- seq(0, 1, by=0.1)
> >> nb <- length(brks)-1
> >> par(mfrow=c(1,2))
> >> plot(r, breaks=brks, col=rev(terrain.colors(nb)), lab.breaks=brks,
> >> zlim=c(0,1))
> >> plot(r2, breaks=brks, col=rev(terrain.colors(nb)), lab.breaks=brks,
> >> zlim=c(0,1))
> >>
> >> It does not work as I expected: the scales are different between graphs.
> >> The first graph has a scale from 0 to 1, and the second one has a
> >> scale from 0 to 0.5. I expected to get a scale from 0 to 1 on both
> >> graphs.
> >> Is this a bug?  Or am I missing something?
> >>
> >> Many thanks,
> >>
> >> Boris
> >>
> >>
> >Hi Boris,
> >
> >During my musings I found this :
> >
> http://stackoverflow.com/questions/4316692/how-can-i-create-raster-plots-with-the-same-colour-scale-in-r
> >
> >This looks strangely similar to your problem...
> >
> >I hope this helps.
> >
> >Best,
> >Arthur
>
>
> Hi Arthur,
>
> thank you for your answer.
> Unfortunately I had also found this thread, but the solution proposed
> doesn't work either.
> The solution proposed in stackoverflow was to define the scale through
> the breaks argument, which was already defined in my previous example.
>
> It is strange because breaks and zlim() seemed to work for a lot of
> people as I could see in several threads, but not here, or not
> anymore.
> Even the example given in the help of ?raster::plot does not seem to work.
>
>
> Maybe my sessionInfo() could help:
>
> R version 2.14.0 (2011-10-31)
> Platform: i386-pc-mingw32/i386 (32-bit)
>
> locale:
> [1] LC_COLLATE=French_France.1252  LC_CTYPE=French_France.1252
> LC_MONETARY=French_France.1252
> [4] LC_NUMERIC=C                   LC_TIME=French_France.1252
>
> attached base packages:
> [1] stats     graphics  grDevices utils     datasets  methods   base
>
> other attached packages:
> [1] raster_1.9-44 sp_0.9-91
>
> loaded via a namespace (and not attached):
> [1] grid_2.14.0    lattice_0.20-0 tools_2.14.0
>
> Thanks for your help,
>
> Boris
>
> _______________________________________________
> R-sig-Geo mailing list
> R-sig-Geo@r-project.org
> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>

	[[alternative HTML version deleted]]

