[R] ploting an ellipse keeps giving errors

[Jari Oksanen]

On Wed, 2004-10-27 at 12:04, Jari Oksanen wrote:
> On Wed, 2004-10-27 at 11:34, Sun wrote:
> > library (ellipse)

Here's your problem! See below.

> > shape1 = c (1, 0, 0,1)
> > dim(shape1) = c(2,2)
> > ellipse (center = c(0,0), shape = shape1, radius = 1)
> > 
> > =============================
> > Error in plot.xy(xy.coords(x, y), type = type, col = col, lty = lty, ...) : 
> >         plot.new has not been called yet
> > 
> > 
> > It is really frustrating. Also what do the shape matrix, radius correspond to an ellipse function
> > 
> > (x-x0)^2/a + (y-y0)^2/b = 1
> > 
> > ? Please advise!
> 
> Sun, did you read the ?ellipse help page? I just read, but I didn't find
> arguments 'center', 'shape' or 'radius' there. It could be useful to use
> argument specified in the help page.  Section 'Details' of ?ellipse
> explains the parametrization.
> 
Sun,

Actually the problem seems to be that you loaded library(ellipse), but
follow the instructions for function ellipse in library(car). Would this
help? (One additional note: ellipse::ellipse.default uses British
spelling for 'centre', but 'cent' would work both in ellipse::ellipse
and car::ellipse.)

cheers, jari oksanen
-- 
Jari Oksanen <jarioksa at sun3.oulu.fi>