[R] Reducing the size of pdf graphics files produced with R

[Chabot Denis]

Hi,

Without trying to print 1000000 points (see <http:// 
finzi.psych.upenn.edu/R/Rhelp02a/archive/42105.html>), I often print  
maps for which I do not want to loose too much of coastline detail,  
and/or plots with 1000-5000 points (yes, some are on top of each  
other, but using transparency (i.e. rgb colors with alpha  
information) this actually comes through as useful information.

But the files are large (not as large as in the thread above of  
course, 800 KB to about 2 MB), especially when included in a LaTeX  
document by the dozen.

Acrobat (not the reader, the full program) has an option "reduce file  
size". I don't know what it does, but it shrinks most of my plots to  
about 30% or original size, and I cannot detect any loss of detail  
even when zooming several times. But it is a pain to do this with  
Acrobat when you generate many plots... And you need to buy Acrobat.

Is this something the pdf device could do in a future version? I  
tried the "million points" example from the thread above and the 55  
MB file was reduced to 6.9 MB, an even better shrinking I see on my  
usual plots.


Denis Chabot