[R] transparent colors

[Uwe Ligges]

See ?rgb and its alpha argument, for example.

Uwe Ligges



Markus Loecher wrote:
> Dear R graphics experts,
> Do you know of any way of plotting semi-transparent points in R ?
> I face this problem any time I want to e.g. plot thousands of points  
> that belong to two or three classes which I color code.
> With the default opaque colors, the plotting order matters and  
> basically the points I plot last completely dominate the picture. I  
> would much rather have the overlaying points mix in color..
> 
> Thanks a lot,
> Markus
> 
> ______________________________________________
> 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.