Hey, i'm trying to set up an cgi web-application that produces maps and other graphics with R. for local testing i used my laptop which has an win xp OS. there everything works fine. now i try to move the whole system over on an unix machine, mainly because i want to establish a connection to a database. anyway, i'm using R 2.0.0 on an other computer in a local network. here comes my problem: i can't create jpeg-files, neither by starting R via my cgi-script nor by pasting the syntax directly into R. both ways i get the following error message: error in X11; unable to start device JPEG; could not open JPEG file. i found out that there is no interactive graphic device for the installed R-Version or it is not set correctly. as i tried dev.interactive(), the response was [1] FALSE. i'm a bit lost at the moment. i wonder if there is a chance to change or modify the interactive graphic device or if i really need to run Xvfb "device" as someone suggested before on the R-help mailing list. does someone has experience with this kind of trouble, any help available from somewhere? thanks in advance, lars
As far as I know, your options are (1) run Xvfb on the unix box, or (2) use the bitmap() device instead of jpeg(). Option 2 will require that ghostscript also be installed on the unix box. Strictly speaking, it doesn't have to to be Xvfb. The requirement is that an X server be running. The R on that unix box probably does have an installed interactive device, but it is not available unless an X server is running, hence your FALSE from dev.interactive(). -Don At 12:49 PM +0200 6/21/05, powdersoul at web.de wrote:>Hey, > >i'm trying to set up an cgi web-application that produces maps and >other graphics with R. for local testing i used my laptop which has >an win xp OS. there everything works fine. now i try to move the >whole system over on an unix machine, mainly because i want to >establish a connection to a database. anyway, i'm using R 2.0.0 on >an other computer in a local network. here comes my problem: > >i can't create jpeg-files, neither by starting R via my cgi-script >nor by pasting the syntax directly into R. both ways i get the >following error message: > >error in X11; unable to start device JPEG; could not open JPEG file. > >i found out that there is no interactive graphic device for the >installed R-Version or it is not set correctly. as i tried >dev.interactive(), the response was [1] FALSE. > >i'm a bit lost at the moment. i wonder if there is a chance to >change or modify the interactive graphic device or if i really need >to run Xvfb "device" as someone suggested before on the R-help >mailing list. does someone has experience with this kind of trouble, >any help available from somewhere? > >thanks in advance, lars > >______________________________________________ >R-help at 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-- -------------------------------------- Don MacQueen Environmental Protection Department Lawrence Livermore National Laboratory Livermore, CA, USA
lars, I use R CMD BATCH as a backend to perl and python CGI all the time. I usually allow R to create post-script (ps) graphics and then use ImageMagick to convert these to PNGs (or JPEGs if you desire). ImageMagick has some nice interfaces to both perl and python. This method produces very sharp looking images. Mark Larsen At 12:49 PM +0200 6/21/05, powdersoul at web.de wrote:>>Hey, >> >>i'm trying to set up an cgi web-application that produces maps and >>other graphics with R. for local testing i used my laptop which has >>an win xp OS. there everything works fine. now i try to move the >>whole system over on an unix machine, mainly because i want to >>establish a connection to a database. anyway, i'm using R 2.0.0 on >>an other computer in a local network. here comes my problem: >> >>i can't create jpeg-files, neither by starting R via my cgi-script >>nor by pasting the syntax directly into R. both ways i get the >>following error message: >> >>error in X11; unable to start device JPEG; could not open JPEG file. >> >>i found out that there is no interactive graphic device for the >>installed R-Version or it is not set correctly. as i tried >>dev.interactive(), the response was [1] FALSE. >> >>i'm a bit lost at the moment. i wonder if there is a chance to >>change or modify the interactive graphic device or if i really need >>to run Xvfb "device" as someone suggested before on the R-help >>mailing list. does someone has experience with this kind of trouble, >>any help available from somewhere? >> >>thanks in advance, lars >