Message-ID: <31493337-17E8-4D61-9774-B1E3CF1B71C8@exeter.ac.uk>
Date: 2009-05-05T18:20:47Z
From: Baptiste Auguie
Subject: quick square root axes
In-Reply-To: <4A007752.3030500@stats.uwo.ca>
On 5 May 2009, at 19:28, Duncan Murdoch wrote:
> On 5/5/2009 1:05 PM, Markus Loecher wrote:
>> Dear R users,
>> while I enjoy the built-in log argument to the plot() function, I
>> wished it
>> would be as easy to create more general custom transformed axes
>> such as
>> sqrt(), logit, etc...
>>
>> for example, instead of
>> plot(x=exp(rnorm(10)), y=(1:10)^4, log = "xy"), sth. along the
>> lines of
>> plot(x=exp(rnorm(10)), y=(1:10)^4, trans = list(x = log, y = sqrt))
>> to encode the desired transfomation.
>>
>> This involves just transforming the xy values and creating nice
>> tick marks
>> at the appropriate positions.
>> Before trying to write my own function, I wanted to see if that
>> functionality already exists in another package ?
>
Have you tried ggplot2? I think Hadley has given a lot of thinking on
this sort of issues.
http://had.co.nz/ggplot2/
http://had.co.nz/ggplot2/coord_trans.html
baptiste
> I don't know of such a thing, but it may well exist.
>
> If you do write your own, the hardest part will be picking the nice
> tick
> marks. They should be approximately evenly spaced, but at nice round
> values of the original variable: that's hard to do in general. R has
> the pretty() function for the linear scale, and doesn't do too badly
> on
> log axes, but you'll need to work out your own rules for the sqrt or
> other scales.
>
> Duncan Murdoch
>
> ______________________________________________
> 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.
_____________________________
Baptiste Augui?
School of Physics
University of Exeter
Stocker Road,
Exeter, Devon,
EX4 4QL, UK
Phone: +44 1392 264187
http://newton.ex.ac.uk/research/emag