Thank you to Brian Ripley and Ray Brownrigg. Using NAs to fill the rectangle
worked. I misunderstood the help file. However, this solution leads to
"jagged" edges where the graph is cut off by NAs (see attachment). I guess I
will have to live with that.
Volker
----- Original Message -----
From: "Prof Brian Ripley" <ripley@stats.ox.ac.uk>
To: "Volker Bahn" <lochapoka@web.de>
Cc: <s-news@wubios.wustl.edu>
Sent: Monday, December 13, 2004 10:00
Subject: Re: [S] non-square persp plot?
|I believe you can fill the *rectangle* with NAs if you want to exclude
| part of the surface. From ?persp
|
| Missing values (NAs) are allowed, but should generally not occur in the
| convex hull of the non-missing values.
|
|
| On Mon, 13 Dec 2004, Volker Bahn wrote:
|
| > Dear list members,
| >
| > I want to create a 3D persp plot that does not cover a square. Is that
| > possible? I calculated predictions from a model for certain parameter
| > combinations of R (growth rate) and death (death rate). However, certain
| > parameter combinations do not lead to results in the model so that I
cannot
| > fill a square matrix with parameter combinations. The death rate cannot
be
| > higher than the growth rate leading to a diagonal cut off in the
possible
| > combinations. When I create a persp() plot from this, I get non-sense
| > extrapolations into the empty parameter space. Is it possible to turn
this
| > off or cut it off? I searched help files and s-news archives but found
| > nothing. The data is posted below (Istd is the model output).
| >
| > Thank you
| >
| > Volker
| >
| > R <- c(1.2, 1.4, 1.6, 1.8, 2, 1.4, 1.6, 1.8, 2, 1.4, 1.6, 1.8, 2, 1.6,
1.8,
| > 2, 1.6, 1.8, 2, 1.8, 2)
| >
| > death <- c(0.1, 0.1, 0.1, 0.1, 0.1, 0.2, 0.2, 0.2, 0.2, 0.3, 0.3, 0.3,
0.3,
| > 0.4, 0.4, 0.4, 0.5, 0.5, 0.5, 0.6, 0.6)
| >
| > Istd <- c(0.3973568, 0.3343699, 0.3183619, 0.3110495, 0.3068442,
0.3516840,
| > 0.3234086, 0.3129532, 0.3074797, 0.3960007, 0.3324119, 0.3162299,
0.3088287,
| > 0.3501716, 0.3216496, 0.3110916, 0.3950060, 0.3309720, 0.3146608,
0.3490352,
| > 0.3203271)
|
| --
| Brian D. Ripley, ripley@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
perspgraph.BMP
Description: Windows bitmap
|
