[R] Legend symbols mixed char and integer

[Mike Prager]

Dear Gurus,

R 2.11.1 on Windows XP.

This is a problem in interaction between R and pdftex.

I need to generate a plot with both open and filled circles. It is
simple enough, using pch=1 and pch=16.

The R pdf graphics output is going into pdftex 1.40.10 (MikTeX 2.8).

The R pdf is correct when viewed in other viewers. However, pdftex
fills the open circles.  I can work around this problem by using
pch="o" for the open circles. However, that messes up the figure
legend. 

Is it possible to use the pch argument of legend() to specify both a
symbol number and a character? I haven't found the way.

Or is there some known work-around for the pdftex bug?

Thanks!

--
Mike Prager, NC, USA