image applied to a sparseMatrix object uses lattice functions to create the image. As described in R FAQ 7.22 you must use
print(image(x)) or show(image(x)) or even plot(image(x)) when a lattice function is called from within another function. On Wed, Apr 28, 2010 at 1:20 PM, Gildas Mazo <gildas.m...@curie.fr> wrote: > Hi, > > I'm getting crazy: > > This does work: > > library(Matrix) > a1<-b1<-c(1,2) > c1<-rnorm(2) > aDgt<-spMatrix(ncol=3,nrow=3,i=a1,j=b1,x=c1) > png("myImage.png") > image(aDgt) > dev.off() > > But this doesn't !!! > > f<-function(x){ > png("myImage.png") > image(x) > dev.off() > } > f(aDgt) > > My image is saved as a text file and contains nothing at all !!! > Thanks in advance, > > Gildas Mazo > > ______________________________________________ > 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-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.