Oftentimes, I see graphs on the web that *look* like they've been produced by R, but I can never be sure. Or can I? I notice that PostScript files include a "%%%Creator: R Software" line, but do R graphics drivers encode any identifying information in GIF or PNG files more commonly used on the web? And of so, would such evidence necessarily be obliterated in post-processing (e.g cropping)? I'm trying to do an informal survey of R's use to create statistical graphics on the web, and if there's a way to identify graph files I see as coming from R it would help a lot. Thanks, # David Smith -- David M Smith <david at revolution-computing.com> Director of Community, REvolution Computing www.revolution-computing.com Tel: +1 (206) 577-4778 x3203 (Seattle, USA)
Hi,
I don't know the answer but here is how I would try to get it from the
source:
$ cd R-devel/src
$ grep -R "R Software" *
Binary file library/grDevices/src/grDevices.so matches
library/grDevices/src/devPS.c: fprintf(fp, "%%%%Creator: R
Software\n");
Binary file library/grDevices/src/devPS.o matches
$ wc library/grDevices/src/*.c
426 1928 10606 library/grDevices/src/chull.c
195 658 5395 library/grDevices/src/devNull.c
775 2771 24480 library/grDevices/src/devPicTeX.c
7592 26813 212324 library/grDevices/src/devPS.c
1375 5342 48939 library/grDevices/src/devQuartz.c
3401 12322 100782 library/grDevices/src/devWindows.c
75 273 2113 library/grDevices/src/init.c
189 807 7436 library/grDevices/src/qdBitmap.c
165 646 5416 library/grDevices/src/qdPDF.c
14193 51560 417491 total
Somewhere in the 14193 lines of code is your answer. Probably also worth
looking in the modules/X11/ and unix directories
Romain
--
Romain Francois
Independent R Consultant
+33(0) 6 28 91 30 30
http://romainfrancois.blog.free.fr
David M Smith wrote:> Oftentimes, I see graphs on the web that *look* like they've been
> produced by R, but I can never be sure. Or can I? I notice that
> PostScript files include a "%%%Creator: R Software" line, but do
R
> graphics drivers encode any identifying information in GIF or PNG
> files more commonly used on the web? And of so, would such evidence
> necessarily be obliterated in post-processing (e.g cropping)?
>
> I'm trying to do an informal survey of R's use to create
statistical
> graphics on the web, and if there's a way to identify graph files I
> see as coming from R it would help a lot.
>
> Thanks,
> # David Smith
>
> --
> David M Smith <david at revolution-computing.com>
> Director of Community, REvolution Computing www.revolution-computing.com
> Tel: +1 (206) 577-4778 x3203 (Seattle, USA)
>
Hi David M Smith wrote:> Oftentimes, I see graphs on the web that *look* like they've been > produced by R, but I can never be sure. Or can I? I notice that > PostScript files include a "%%%Creator: R Software" line, but do R > graphics drivers encode any identifying information in GIF or PNG > files more commonly used on the web? And of so, would such evidence > necessarily be obliterated in post-processing (e.g cropping)?I know that pdf() adds similar "Creator" information. I don't recall seeing anything like this for the raster devices, but I've worked less with them so I don't know for sure. Paul> I'm trying to do an informal survey of R's use to create statistical > graphics on the web, and if there's a way to identify graph files I > see as coming from R it would help a lot. > > Thanks, > # David Smith > > -- > David M Smith <david at revolution-computing.com> > Director of Community, REvolution Computing www.revolution-computing.com > Tel: +1 (206) 577-4778 x3203 (Seattle, USA) > > ______________________________________________ > R-devel at r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-devel-- Dr Paul Murrell Department of Statistics The University of Auckland Private Bag 92019 Auckland New Zealand 64 9 3737599 x85392 paul at stat.auckland.ac.nz http://www.stat.auckland.ac.nz/~paul/