similar to: How to plot a 3D ellipsoid in R?

I have a 3xN matrix of parameters obtained from N regressions where the 3 parameters are jointly statistically significant. I would like to reproduce a 3D confidence ellipsoid projecting 2D ellipses onto the XY plane as in Figure 5.2 in this

Dear all, Has anyone written functions to compute (and ideally project / plot onto a plane) confidence ellipsoids for q linear model parameters, q > 2 ? Greetings and best wishes, Renaud -- Dr Renaud Lancelot, v?t?rinaire CIRAD, D?partement Elevage et M?decine V?t?rinaire (CIRAD-Emvt) Programme Productions Animales http://www.cirad.fr/presentation/programmes/prod-ani.shtml ISRA-LNERV

Hello, in a three dimensional coordinate system, I'd like to find all my experimental data points that fall within an ellipsoid around a fixed coordinate. The fixed point is defined by (x.coord.point, y.coord.point, z.coord.point). The coordinates of the ellipsoid are given by the three vectors x,y,z. In a previous version of my code, I simply used a box instead of an ellipsoid to sort

Dear all, I would like to draw a 3-D horizontal cylinder preferably in RGL device (because this gives the look from different angles). Basic idea is from http://www.tau.ac.il/cc/pages/docs/sas8/insight/chap18/sect3.htm. Below is the description exactly what I want to do. Please see at figure 18.6, 1st plot. Here it is an confidence ellipsoid. Suppose now you put another 4 same ellipsoids on top

+ Hello, The parametric equations of an ellipsoid can be written in terms of spherical coordinates. The three spherical coordinates are converted to Cartesian coordinates by X=a cos (α) sin(θ) Y=b sin(α) sin(θ) Z=c cos(θ) for α and θ The parameter α varies from 0 to 2 π and θ varies from 0 to π . Here ( X o , Y o ,Z o ) is the center of the ellipsoid, and θ is the angle

Hi all, How do I visualize a contour of a tri-variate normal distribution? I just like to see the ellipsoid very much. I hope there is a easy way or existing method in R. Thank you a lot! Michael. [[alternative HTML version deleted]]

Hi all, Can anyone please guide me how to draw a Concentration ellipsoid for a bivariate system with a bivariate normal dist. having a VCV matrix : Sigma <- matrix(c(1,2,2,5), 2, 2) I would like to draw in using GGPLOT. Your help will be highly appreciated. Thanks, -- View this message in context: http://www.nabble.com/Concentration-ellipsoid-tp25315705p25315705.html Sent from the R help

Dear list, I'm trying to visualise some ellipsoidal shapes in 3D. Their position, axes, and angular orientation can be arbitrary. I saw an ellipse3d function in rgl; however it is heavily oriented towards the statistical concept of ellipse of confidence, whilst I am just concerned with the geometrical object. Below is my current implementation. It is quite slow when creating many shapes, so

John Fox wrote: >The confidence ellipse for a pair of coefficients is just (with an >adjustment for size) the perpendicular shadow of the joint ellipsoid, in >the same sense that the confidence intervals for individual coefficients >are shadows of the joint ellipsoid or ellipse. The usual confidence ellipse >for 2 of q coefficients uses qf(.95, 2, df.error) to scale the ellipse; if

For a paper dealing with generalized ellipsoids, I want to illustrate in 3D an ellipsoid that is unbounded in one dimension, having the shape of an infinite cylinder along, say, z, but whose cross-section in (x,y) is an ellipse, say, given by the 2x2 matrix cov(x,y). I've looked at rgl:::cylinder3d, but don't see any way to make it accomplish this. Does anyone have any ideas? thx,

Hello, I'm working with a series (30+) of hydrologic metrics and 10 vegetation communities and I need to determine which of the metrics provide the best separability for each of the vegetation communities. The hydrologic metrics are highly correlated, therefore the need to reduce the number of them considered is critically important. I've been looking at the scatter3d function in the

Dear All, The Minimum Volume Ellipsoid estimator ("cov.mve") was part of S+ but I cannot find it in R. Where can I find it? Why was it excluded? Cheers, Patrik Sweden

I am interested in making a random sample from a uniform distribution of points over the surface of the earth, using the WGS84 ellipsoid as a model for the earth. I know how to do this for a sphere, but would like to do better. I can supply random numbers, want latitude longitude pairs out. Can anyone point me at a solution? Thanks very much. -- Russell Senior ``I have nine fingers;

Dear list, I've generated a list of 3D coordinates representing ellipsoids in arbitrary orientations. I'm now trying to obtain a 2D projection of the scene, that is to draw the silhouette of each object on a plane (x,y). The only way I could think of is to compute the convex hull of the (x,y) coordinates of each object and use this as the outline of the object. This is clearly

I am curious if there is code developed to plot confidence regions in 3D. The scatterplot3d function generates the plot I want, but would like an 3D equivalent to the data.ellipse function. Any help in this direction would be appreciated, be it theoretical, graphical, or otherwise. Melanie Edwards Senior Statistician Exponent 15375 SE 30th PL, Suite 250 Bellevue, WA 98007 Tel: (425) 519-8714

Dear Subscribers, I am using R for quite a while nowadays on Ubuntu 10.04 LTS. I a using R for doing my statistics. Furthermore I am using it as a tool to generate the graphics for my publications. I am currently working on a project which involves nls-fits of three dimensional surfaces such as ellipsoids or even more complex. I have been searching R help and the manuals for a possibility to

Dear all, I write to the community to know if other people expierenced the same problem. I want to save a rgl scene where I plotted a 3d cloud of spheres whose radius is set proportional to a given variable and coloured by another group variable and with 95% ellipsoids for distribution of any group. I had no problem at all for coding but I had two problem when saving the scene (in any format)

Hi, does anyone know how to plot 3D parametric surface,e.g ellipsoid: x=a*cos(s)*cos(t), y=b*sin(s)*cos(t), z=sin(t); s in [0,2*pi], t in [-pi,pi]. Vytautas Maniusis, Vilnius University, Lithuania

hello, I wish to create some 3d scatter diagrams visualising different grouped data set by a given field in the database. I tried the scatterplot3d package, as well as the plot3d and scatter3d functions (both within the rgl resp. Rcmdr package). My first question is, whether is it possibe to group data in the scatterplot3d and plot3d, because I did not succeed to use the groups = ...

Dear R-help, Can some one tell me how to do the following (if it's possible)? Suppose I have a function like this: f <- function(x, y, ...) { ## some code g(x, y, ...) ## some more code } The problem is that g() may not understand everything that comes through in "...". Is there a way to delete some component of "..." and then pass it to g()? Here's