[R] in axis() suppressing axis line but keeping tick marks

[Prof Brian Ripley]

I'm pretty sure that this is not Paul's design and he usually doesn't want 
to touch base graphics.

I've added arguments lwd.ticks and col.ticks in R-devel.  The simplest way 
to suppress the axis line become axis(..., lwd=0, lwd.ticks=1).

On Mon, 16 Jun 2008, Peter Dalgaard wrote:

> Andrew Yee wrote:
>> I've been trying to figure out a parameter that will let you separately
>> adjust the parameters for the axis line from the tick mark.
>> 
>> In the following example, I would like to suppress the axis line, but keep
>> the tick marks.
>> 
> The source code is the ultimate reference. We have in do_axis in 
> src/main/plot.c:
>
>   if (doticks) {
>       gpptr(dd)->col = col;/*was fg */
>       GLine(axis_low, axis_base, axis_high, axis_base, NFC, dd);
>       for (i = 0; i < n; i++) {
>           x = REAL(at)[i];
>           if (low <= x && x <= high) {
>               x = GConvertX(x, USER, NFC, dd);
>               GLine(x, axis_base, x, axis_tick, NFC, dd);
>           }
>       }
>   }
>
> and, as you see, there is no way the line parameters can change between the 
> GLine calls, no hope of finding a magical par() setting. So I'm afraid you 
> have to bite the bullet, do the relevant coordinate calculations, and use 
> segments() do draw the ticks. (Or try convincing Paul Murrell to change the 
> design, but that takes longer...).
>
> --
>  O__  ---- Peter Dalgaard             Øster Farimagsgade 5, Entr.B
> c/ /'_ --- Dept. of Biostatistics     PO Box 2099, 1014 Cph. K
> (*) \(*) -- University of Copenhagen   Denmark      Ph:  (+45) 35327918
> ~~~~~~~~~~ - (p.dalgaard at biostat.ku.dk)              FAX: (+45) 35327907
>
> ______________________________________________
> 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.
>

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595