Logarithmic legend
Hello,
I have been working on a suitable approach with lattice and raster. Now
you can use levelplot with a logarithmic scale both for the colorkey and
the contour lines.
First you have to install the 0.10-6 version of rasterVis from R-Forge:
install.packages("rasterVis", repos="http://R-Forge.R-project.org")
library(raster)
library(rasterVis) ## 0.10-6
f <- system.file("external/test.grd", package="raster")
r <- raster(f)
levelplot(r, zscaleLog=10, contour=TRUE, labels=TRUE)
Still in development!
Cheers,
Oscar.
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Oscar Perpi??n Lamigueiro
Dpto. Ingenier?a El?ctrica
EUITI-UPM
http://procomun.wordpress.com
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Hi, You could use ggplot: library(gstat) library(ggplot2) loadMeuse() meuse.grid.df = as.data.frame(meuse.grid) head(meuse.grid.df) # Create a dist + 1 for log transformation # prevents -Inf for 0 values meuse.grid.df$dist_plus1 = meuse.grid.df$dist + 1 ggplot(aes(x = x, y = y, fill = dist_plus1), data = meuse.grid.df) + geom_tile() + coord_equal() + scale_fill_continuous(trans="log") # Some theme changes I like theme_set(theme_bw()) ggplot(aes(x = x, y = y, fill = dist_plus1), data = meuse.grid.df) + geom_tile() + coord_equal() + scale_fill_continuous(trans="log") hope this helps, Paul On 10/05/2011 06:21 PM, Arnaud Mosnier wrote:
Dear Geo Users, Please, can someone explain me how to plot a raster using a logarithmic scale and obtaining the legend with this scale ? Thanks for any help, Arnaud [[alternative HTML version deleted]]
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