[Rd] text(x, y, labels) - recycling problems and RFC (PR#7084)

[Prof Brian Ripley]

On Thu, 19 Aug 2004 maechler at stat.math.ethz.ch wrote:

> I didn't get any feedback on this posting,
> 
> so I will commit my proposal to recycle the coordinates (x,y) to
> the length of 'labels' if the latter is longer  (instead of
> silently dropping the extra labels[] entries).

I'd suggest only doing non-fractional recycling (or at the very least 
warning against fractional recycling).  I would expect almost all 
occurrences of your example would be unintended.


> 
> Martin Maechler
> 
> >>>>> "MM" == Martin Maechler <maechler at stat.math.ethz.ch>
> >>>>>     on Tue, 13 Jul 2004 18:22:05 +0200 (CEST) writes:
> 
>     MM> Not a bug necessarily, in text(), but at least an inconsistency,
>     MM> and a need for more documentation:  Contrary to e.g., plot(),
>     MM> text(x,y,labels) *does* recycle it's arguments to some extent --
>     MM> and probably has always in S.
> 
>     MM> However it doesn't do all I think it should, i.e.,
> 
>     MM> plot(1:7); text(1:2, 1+ 1:3, LETTERS[1:4])
> 
>     MM> does recycle 'x' to c(1:2, 1) {length 3} to match 'y'
>     MM> but doesn't recycle to length 4 in order to match 'labels'.
> 
>     MM> While one can well accept this, I believe it should give a
>     MM> warning since it silently 'drops' the "d".
> 
>     MM> However, I'm proposing to consider S(-plus) compatibility here.
>     MM> In S-PLUS 6.1, the result of the above is
>     MM> identical to
>     MM> plot(1:7); text(rep(1:2,length=4), rep(1+ 1:3, length=4), LETTERS[1:4])
>     MM> i.e. (x,y) is recycled to length 4, the length of 'labels'.
> 					
>     MM> Further note that in
>     MM> plot(1:7); text(1:2, 1+ 1:3, LETTERS[1:2], col=2:6)
>     MM> the 'labels' *are* recycled to length 3, matching (x,y) -- but
>     MM> not to length 5 of 'col' which is fine -- just not the other way around.
> 
>     MM> I'd propose that R should recycle all three (x,y,labels)
>     MM> [but not more] to common length.
> 
>     MM> BTW, "grid" graphics do recycle as well, at least  
>     MM> grid.text(labels, x, y) does --- and as I see it does also
>     MM> recycle at least the 'rotation'.
> 
>     MM> Martin Maechler
> 
>     MM> ______________________________________________
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>     MM> https://www.stat.math.ethz.ch/mailman/listinfo/r-devel
> 
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> 

-- 
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