[R] Can't load Rgraphviz on windows-based R

[Prof Brian Ripley]

Rgraphviz is a Bioconductor package, so please ask on the apporpriate 
mailing list (see the posting guide).

On Tue, 2 Dec 2008, Daren Tan wrote:

>
> Hi,
>
> I have problem loading Rgraphviz. Following the instructions specified by the README in Rgraphviz_1.20.3.tar.gz didn't help either.
>
> o. set the following Windows environment variables accordingly
>   (control panel -> systems -> Advanced -> Environment Variables ):
>   (a) create new user variables:
>     GRAPHVIZ_INSTALL_DIR   (e.g., C:\Graphviz-2.21) <-------------------------- I stated C:\Graphviz-2.21 (I also tried C:\/Graphviz-2.21)
>     GRAPHVIZ_INSTALL_MAJOR (e.g., 2)                <-------------------------- I stated 2
>     GRAPHVIZ_INSTALL_MINOR (e.g., 20)               <-------------------------- I stated 21
>     Notice the way "\/" are used for the paths above.
>   (b) add to user variable 'path': $GRAPHVIZ_INSTALL_DIR/bin
>     e.g., C:\Graphviz-2.21\bin                      <-------------------------- I stated C:\Graphviz-2.21\bin (I also tried C:\/Graphviz-2.21\/bin)

It should be 'PATH', not 'path': environment variables are case-sensitive 
(in general, not sure what happens with PATH if set there).

>> library("Rgraphviz")
> Error in inDL(x, as.logical(local), as.logical(now), ...) :
>  unable to load shared library 'D:/PROGRA~1/R/R-28~1.0/library/Rgraphviz/libs/Rgraphviz.dll':
>  LoadLibrary failure:  The specified module could not be found.

That does not mean Rgraphviz.dll: it means a dependent DLL.  You did 
actually install graphviz, I presume?

> In addition: Warning messages:
> 1: closing unused connection 4 (D:/PROGRA~1/R/R-28~1.0/library/Rgraphviz/libs/Rgraphviz.dll)
> 2: closing unused connection 3 (D:/PROGRA~1/R/R-2.8.0/library/Rgraphviz/libs/Rgraphviz.dll)
> Error : .onLoad failed in 'loadNamespace' for 'Rgraphviz'
> Error: package/namespace load failed for 'Rgraphviz'
>
>> file.exists("D:/PROGRA~1/R/R-28~1.0/library/Rgraphviz/libs/Rgraphviz.dll")
> [1] TRUE
>
>> sessionInfo()
> R version 2.8.0 (2008-10-20)
> i386-pc-mingw32
> locale:
> LC_COLLATE=English_United States.1252;LC_CTYPE=English_United States.1252;LC_MONETARY=English_United States.1252;LC_NUMERIC=C;LC_TIME=English_United States.1252
> attached base packages:
> [1] grid      stats     graphics  grDevices utils     datasets  methods   base
> other attached packages:
> [1] graph_1.20.0
> loaded via a namespace (and not attached):
> [1] cluster_1.11.11 tools_2.8.0
>
> ______________________________________________
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> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595