If you are willing to go to the bother of representing your data as a sparse matrix, the package SparseM has a version of image() that will do what you would like to do, I believe.
url: www.econ.uiuc.edu/~roger Roger Koenker email [EMAIL PROTECTED] Department of Economics vox: 217-333-4558 University of Illinois fax: 217-244-6678 Champaign, IL 61820 On Aug 17, 2007, at 1:51 PM, baptiste Auguié wrote: > Hi, > > New to R, I don't find a way to plot the following data with image(): > > x is a N * M matrix > y is a vector of length M > z is a N*M matrix > > I wish to plot z as a greyscale image, but my x axis is different for > every row of the z data. > > Here is a minimal example, > >> theta<-c(3:6) # N >> y<-c(1:5) # M >> >> x<-theta%*%t(y)# N * M >> z<-sin(x) # N * M >> >> image(z) > > This doesn't give what I want, as the x axis needs to be shifted as > we go from line to the following. (probably clearer if you plot > matplot(x,z): the curves are shifted) > > The way I see it, I need either to construct a bigger matrix with all > possible values of x giving the new dimension and arbitrary values > for the missing points, or find a plotting function that would plot > lines by lines. The ordering of the x and z values is giving me a > headache on the first idea, and I can't find any option / alternative > to image. > > Thanks in advance! > > baptiste > > ______________________________________________ > R-help@stat.math.ethz.ch 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-help@stat.math.ethz.ch 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.
