Use the matrix of colours directly: nx <- 100 ny <- 100 m <- matrix(data = rep(seq(0,1, length = nx), ny), ncol = nx, nrow = ny, byrow = TRUE) plot(1:nx, 1:ny, type = "n") my.color <- matrix(data = (rainbow(100))[m*100], ncol = nx, nrow = ny, byrow = TRUE) rasterImage(my.color, 1, 1, nx, ny)
Also, you might want to check out image.SpatialGridDataFrame in package sp that provides a wrapper around rasterImage for SpatialGrids. I'm not aware of other examples, but I have not looked hard since the first release of rasterImage. library(sp) sp:::image.SpatialGridDataFrame Cheers, Mike. On Fri, Oct 1, 2010 at 12:50 PM, Ben Tupper <ben.bigh...@gmail.com> wrote: > Hello, > > I have been exploring the possibility to transition some code that currently > uses image() to use the new rasterImage(). To date, I haven't been able to > specify a color look-up strategy that works. For example... > > nx <- 100 > ny <- 100 > m <- matrix(data = rep(seq(0,1, length = nx), ny), ncol = nx, nrow = ny, > byrow = TRUE) > plot(1:nx, 1:ny, type = "n") > my.color <- matrix(data = (rainbow(100))[m*100], ncol = nx, nrow = ny, byrow > = TRUE) > rasterImage(m, 1, 1, nx, ny, col = my.color) > > This yields a greyscale image. Is it possible to create colored images using > rasterImage, and, if so, what is the correct way to generate a colored image > using rasterImage? > > Also, is there a vignette or tutorial on using the new rasterImage() and > related functions? > > Thanks! > Ben Tupper > Bigelow Laboratory for Ocean Science > www.bigelow.org > >> R.Version() > $platform > [1] "i386-apple-darwin9.8.0" > > $arch > [1] "i386" > > $os > [1] "darwin9.8.0" > > $system > [1] "i386, darwin9.8.0" > > $status > [1] "" > > $major > [1] "2" > > $minor > [1] "11.1" > > $year > [1] "2010" > > $month > [1] "05" > > $day > [1] "31" > > $`svn rev` > [1] "52157" > > $language > [1] "R" > > $version.string > [1] "R version 2.11.1 (2010-05-31)" > > ______________________________________________ > 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. > -- Michael Sumner Institute for Marine and Antarctic Studies, University of Tasmania Hobart, Australia e-mail: mdsum...@gmail.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.
