From Greg.Snow at imail.org  Thu Feb  5 22:15:28 2009
From: Greg.Snow at imail.org (Greg Snow)
Date: Thu, 5 Feb 2009 14:15:28 -0700
Subject: [Rd] "open-ended" plot limits?
In-Reply-To: <498B528A.6080105@comcast.net>
References: <XFMail.090205204833.Ted.Harding@manchester.ac.uk>
	<498B528A.6080105@comcast.net>
Message-ID: <B37C0A15B8FB3C468B5BC7EBC7DA14CC61CA00CBC1@LP-EXMBVS10.CO.IHC.COM>

I use range( 0, y ) rather than c(0, max(y)), that way if there are any y values less than 0, the limits still include them (and it is slightly shorter :-).

This also extends to cases where you may know that you will be adding additional data using points or lines, so you can do ylim=range(0, y1, y2, y3) and it will give enough room to add the other y variables in latter.

Hope this helps, 

-- 
Gregory (Greg) L. Snow Ph.D.
Statistical Data Center
Intermountain Healthcare
greg.snow at imail.org
801.408.8111


> -----Original Message-----
> From: r-devel-bounces at r-project.org [mailto:r-devel-bounces at r-
> project.org] On Behalf Of Marc Schwartz
> Sent: Thursday, February 05, 2009 1:57 PM
> To: ted.harding at manchester.ac.uk
> Cc: R-Devel
> Subject: Re: [Rd] "open-ended" plot limits?
> 
> on 02/05/2009 02:48 PM (Ted Harding) wrote:
> > Hi Folks,
> > Maybe I've missed it already being available somehow,
> > but if the following isn't available I'd like to suggest it.
> >
> > If you're happy to let plot() choose its own limits,
> > then of course plot(x,y) will do it.
> >
> > If you know what limits you want, then
> >   plot(x,y,xlim=c(x0,x1),ylim(y0,y1)
> > will do it.
> >
> > But sometimes one would like to
> > a) make sure that (e.g.) the y-axis has a lower limit (say) 0
> > b) let plot() choose the upper limit.
> >
> > In that case, something like
> >
> >   plot(x,y,ylim=c(0,NA))
> >
> > would be a natural way of specifying it. But of course that
> > does not work.
> >
> > I would like to suggest that this possibility should be available.
> > What do people think?
> >
> > Best wishes,
> > Ted.
> 
> Ted,
> 
> Unless I am mistaken in what you are looking for:
> 
>   plot(x, y, ylim = c(0, max(y)))
> 
> would seem do what you want. If otherwise unspecified, plot() uses
> range(y) to define 'ylim'.
> 
> HTH,
> 
> Marc Schwartz
> 
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel



[Rd] "open-ended" plot limits?
Greg Snow