[R] 300 dpi and eps:

Aldi Kraja aldi at wustl.edu
Wed Dec 15 16:47:44 CET 2010


I have come around several times from R to A. Illustrator, or A. 
photoshop, and between them with PowerPoint. It is possible that the 
last one I reported was from PowerPoint.
So from your postings it was made clear that postscript plot from R 
produces a vector graph.

Can someone recommend some paper that makes clear the relation and 
distinctions between vector and raster graphics, but especially with 
some practical examples in regard to what is the relation between page 
(height and width) and dpi.

For example if I plan to print high resolution graph in an image size of 
the A4 paper (8.5 inch x 11 inch) and from a journal it is required that 
the graph needs to have 300 dpi or more how one tells to the R graphical 
device to produce this setting?

In A. photoshop for example I can define for a graph width in inches, 
height in inches and resolution in pixels/inch color model CMYK and 8 
bit. How one works in R?

Or one saves the graph from postscript function as eps or tiff and you 
tell to the editor of the journal do whatever you want because I am 
done; I provided you already a vector graph that has infinite pixels?:-)

Thank you advance,

Aldi

On 12/15/2010 3:52 AM, Rainer M Krug wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> On 12/15/2010 09:31 AM, Philipp Pagel wrote:
>>> Everything works fine to place them in a pdf file , or eps file, but
>>> when it comes to have a high quality of 300 dpi these graphs are not
>>> good. For example I open the eps file with Adobe Illustrator (AI)
>>> and it shows that it is a 72dpi graph.
>> This is simply not true: it's an eps and thus of essentually infinite
>> resolution for all practial purposes.
> Just to clarify this: eps / ps are vector formats - i.e. it says in the
> file "draw a line from point x to point y". In contrast, bmp (and e.g.
> jpg, png, tiff) are raster formats: in these formats save the PICTURE of
> the line from point x to y.
> Consequently, only raster formats have dpi ("dots" per inch).
>
>> So your problem is not with
>> the R-generated eps but somewhere downstream from that. Any
>> postprocessing, conversion or editing?
> Or in Adobe illustrator? It strikes me, that 72dpi is usually the screen
> resolution.
>
> Cheers,
>
> Rainer
>
>> cu
>> 	Philipp
>>
>
> - -- 
> Rainer M. Krug, PhD (Conservation Ecology, SUN), MSc (Conservation
> Biology, UCT), Dipl. Phys. (Germany)
>
> Centre of Excellence for Invasion Biology
> Natural Sciences Building
> Office Suite 2039
> Stellenbosch University
> Main Campus, Merriman Avenue
> Stellenbosch
> South Africa
>
> Tel:        +33 - (0)9 53 10 27 44
> Cell:       +27 - (0)8 39 47 90 42
> Fax (SA):   +27 - (0)8 65 16 27 82
> Fax (D) :   +49 - (0)3 21 21 25 22 44
> Fax (FR):   +33 - (0)9 58 10 27 44
> email:      Rainer at krugs.de
>
> Skype:      RMkrug
> -----BEGIN PGP SIGNATURE-----
> Version: GnuPG v1.4.10 (GNU/Linux)
> Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/
>
> iEYEARECAAYFAk0Ij8gACgkQoYgNqgF2egolFwCfbcSKiB4xyc7B/mOzdRRu2/dr
> iOEAn1KoMR1C4RgYuRRIixUVtLbXN1zE
> =W0bk
> -----END PGP SIGNATURE-----
>
> ______________________________________________
> R-help at 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.

--



More information about the R-help mailing list