[Rd] How to link to vignette from .Rd file

[Dominick Samperi]

Duncan Murdoch wrote:
> On 11/7/2006 8:51 AM, Agner Fog wrote:
>   
>> I am building a package for various noncentral hypergeometric distributions.
>>
>> I want to include some heavy mathematical formulas. It appears that the 
>> build and INSTALL commands produce only .chm files and not .pdf files 
>> from my .Rd files under Windows. This means that it cannot show 
>> complicated mathematical formulas.
>>
>> The solution might be to include a .pdf file as a vignette. I tried 
>> that, but I can't find any way to link to the .pdf file or access it 
>> from any of the help facilities. The .pdf file is useless if the user 
>> can't find it.
>>     
>
> Yes, that's a major problem in the current R help system.  You can give 
> the user code that would work to show the vignette, but there's no way 
> to create a live link to it.
>   
The demo system can be used to compensate for limitations of the help 
system.
You can display PDF files from any package subdirectory using a demo file
like this (named demo/ReadPkgDoc.R, and documented in demo/00Index):

# ReadPkgDoc.R -- Displays a PDF file as a demo
#
isWindows <- (Sys.info()['sysname'] == 'Windows')
file <- system.file("doc", "PkgManual.pdf", package="PkgName")
if(isWindows) { # Windows automatically finds executable based on file type.
  system(paste("CMD /C ", file, "\n"))
} else { # Change this to use path to Adobe reader if desired.
  system(paste("xpdf ", file, "\n"))
}

To create the PDF file from the Rd file use R CMD Rd2dvi, and dvipdf.

ds