On Fri, Aug 28, 2009 at 7:16 AM, Gábor Csárdi<csa...@rmki.kfki.hu> wrote: > On Fri, Aug 28, 2009 at 1:06 PM, Oliver Bandel<oli...@first.in-berlin.de> > wrote: > [...] >> The goal was to produce a picture in a web-environment. >> >> At the moment rpy2 will be used.... maybe there are way to achieve something >> like that in this way, but I'm also new to rpy2. >> >> When the graphic could be written to stdout, the calling environment could >> reead >> it from the forked process. >> >> But maybe rpy2 works different. >> >> Any ideas on that on-the-fly creation of pictures? >> If there would be no temporary files this would be fine. >> That's the reason why I looked for stdout as output channel. > > Oliver, > > I have a similar problem and had a similar question on the list about > a week ago.... all I could find out that some devices of the Cairo > package are supposed to support plotting to R connections (including > stdout), but it does not work in practice: > >> library(Cairo) >> tc <- textConnection("foo", "w") >> CairoPNG(file=tc) > Error in Cairo(width, height, type = "png", file = filename, pointsize > = pointsize, : > file must be a filename. to support writing to a connection, > recompile R and Cairo with the R Connection Patch. > > Information on the "R connection Patch" is welcome. Recompiling R and > Cairo is not a problem for me, I am putting together a special > environment anyway. > > Best, > Gabor > > [...] >
I could have used this functionality in a previous project as well; however, for Oliver's application just pass the filename to the python program use that in the <img src=...> tag (or have the python program pass the filename to the R program). If there is some aspect of this problem that has not been explained that truly does make passing the graphic file contents to the python program desirable then have R write out the graphic file and then have R read it back in. ______________________________________________ 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.