[R] display double dot over character in plotmath?

[Ranjan Maitra]

On Sun, 14 May 2017 09:08:46 -0700 David Winsemius <dwinsemius at comcast.net> wrote:

> 
> > On May 14, 2017, at 8:43 AM, Ranjan Maitra <maitra at email.com> wrote:
> > 
> > Thanks, Duncan!
> > 
> > This works for the particular case and is, to my mind, a great solution!
> > 
> > However, I was wondering: is it possible to use these double dots with another character, such as omega?  
> > 
> > I apologize for changing the question somewhat, but I did not realize earlier that there were separate codes for putting double dots over different letters and I thought that figuring out the simpler question would be enough for me to figure out the next step. 
> 
> I think you should be looking for a LaTeX solution. There is a tikzDevice-package.
> 
> This says you can assemble symbols with backspaces:
> 
> https://www.stat.berkeley.edu/~partha/symbols.pdf
> 
> For instance, LATEX defines \hbar (“~”) as a “¯” character (\mathchar’26) followed by a backspace of 9 math units (\mkern-9mu), followed by the letter “h”:
> 
> The second example in ?tikz, which could be a starting point for completing your task fails on my Mac by only displaying the names of the glyphs but not the glyphs themselves in the plot,  but it might have a better chance of succeeding on a Linux box.


Thanks! I was trying to avoid using tikz but I guess that there may well be no other alternative.

Best wishes,
Ranjan