Greetings,
I'm trying to debug a simple two-line plot routine in R called test.R:
cor(swiss)
plot(swiss$Catholic, swiss$Examination)
These commands work fine when typed into R. They also work fine when
I invoke this routine by the following line into my terminal:
R --slave < /Library/WebServer/Documents/gsa/test.R
My ultimate goal is to send data to this R routine via a web interface
mediated by Ruby. However, I've run into a wall there -- the commands
that work fine when typed directly into the command line, fail when
sent via Ruby.
1. I start with a simple HTML page that calls a simple two-line Ruby
CGI program (gsa.cgi):
#!/usr/bin/ruby
system("R --slave < /Library/WebServer/Documents/gsa/test.R")
2. However, when I hit the submit button on the HTML page, I get the
following error messages on my Apache 2 server log:
[Tue Aug 11 01:22:41 2009] [error] [client ::1] Error in function
(file = ifelse(onefile, "Rplots.pdf", "Rplot%03d.pdf"), :
[Tue Aug 11 01:22:41 2009] [error] [client ::1] unable to start
device pdf
[Tue Aug 11 01:22:41 2009] [error] [client ::1] Calls: plot ...
plot.default -> plot.new -> <Anonymous> -> .External
[Tue Aug 11 01:22:41 2009] [error] [client ::1] In addition: Warning
message:
[Tue Aug 11 01:22:41 2009] [error] [client ::1] In function (file =
ifelse(onefile, "Rplots.pdf", "Rplot%03d.pdf"), :
[Tue Aug 11 01:22:41 2009] [error] [client ::1] cannot open 'pdf'
file argument 'Rplots.pdf'
[Tue Aug 11 01:22:41 2009] [error] [client ::1] Execution halted
3. If I comment out the line in test.R with the plot command, all
works fine.
FWIW, I'm running this on a MacBook Pro OS X 10.5.8 with Ruby 1.8.7
Any assistance would be gratefully accepted.
Regards,
Michael L. Richardson, M.D.
University of Washington Radiology
______________________________________________
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.
