Displaying 20 results from an estimated 3000 matches similar to: "which points within an ellipsoid? Sorting data in 3d"
2011 Nov 05
1
3-D ellipsoid equations
+
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
2007 Aug 13
2
help with scatterplot3d
Hello,
I am having a bit of trouble with scatterplot3d().
I was able to plot a 3d cloud of points using the following code:
>my.3dplot<-scatterplot3d(my.coords, pch=19, zlim=c(0,1), scale.y=0.5,
angle=30, box=FALSE)
where my.coords is a data frame that contains x, y, and z coordinates for
grid points whose elevation we sampled.
The problem occurs when I try to add points using points3d.
2007 Apr 04
1
rgl.postscript generating pdf: floating xlab, font size, transparency
Hello,
I very much enjoy rgl! But when converting the screen output to pdf
using rgl.postscript I have encountered three problems:
(1) I don't seem to have control over font sizes and point sizes (of
added points) in the pdf output. I tried cex from "plot" but that
does not have an effect. Initially I got some plots where fonts and
especially points were far too small. But now
2009 Sep 06
1
Concentration ellipsoid
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
2012 Feb 07
2
3D confidence ellipsoid with ellipse projections onto 2D plane
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
2002 Dec 05
1
How to plot a 3D ellipsoid in R?
Hey, all
I am going to plot several 3-dimensional ellipsoids
in R.
For example, A is such a ellipsoid with
mean u=[1 1 1]', covariance matrix C=[1 0 .5;0 1 .6;.5 .6 1];
So how can I plot such object in 3D space?
Is there some function to achieve this?
Thanks.
Fred
2002 Jan 04
1
[S] confidence ellipsoid for model parameters
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
2006 Apr 26
1
Minimum Volume Ellipsoid Estimator ("cov.mve"??)
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
2007 Feb 21
1
random uniform sample of points on an ellipsoid (e.g. WGS84)
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;
2002 Jan 01
3
confidence ellipsoid for model parameters
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
2013 Jan 18
2
How to re-project ease( Equal Area Scalable Earth) grid with a ~25 km cylindrical projection to WGS84 0.25 degree?
I have nc files for global soil moisture,here is one file
https://echange-fichiers.inra.fr/get?k=f9DDllPKdUKs5ZNQwfq
from the metadata ,the projection is cylindrical and the resolution is 25
km(it is based on authalic sphere based on International 1924 ellipsoid).As
I want to compare with other data, I have to make them identical.
- my other data are in WGS84 with 0.25*0.25 degree resolution
2012 Feb 16
1
Is there a function for scatter3d with Categorical responses?
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
2008 May 13
1
3dscatterplot -different colors for different factors of the same variable
Dear R users,
I was trying to do a 3d scatterplot for the following set of datas:
"obj" "time" "X" "Y"
"1" "yellow" "333" "388.7" "492.3"
"2" "yellow" "567" "388.7" "492.3"
"3" "green" "621" "135.5"
2011 Jan 31
1
rgl: draw multiple ellipsoids
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
2009 Jan 13
3
problem whit Geneland
I do the these passages:
library(Geneland)
set.seed(1)
data <- simdata(nindiv=200,
coord.lim=c(0,1,0,1) ,
number.nuclei=5 ,
allele.numbers=rep(10,20),
IBD=FALSE,
npop=2,
give.tess.grid=FALSE)
geno <- data$genotypes
coord <- t(data$coord.indiv)
path.mcmc <-
2005 Jun 28
1
3D ellipsoid confidence region
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
2010 Apr 05
1
Using pch with the RGL library
Hi,
I am trying to compare two 3D plots. For that, I am trying to use the
"pch" parameter in the "points3d" function, but it is not working. Is
it implemented? Any suggestion?
Here goes a reproducible code. I wanted the second plot having
different symbols for the points.
x <- rbind(matrix(rnorm(100, sd = 0.3), ncol = 2),
matrix(rnorm(100, mean = 1, sd = 0.3),
2012 Dec 07
1
points3d and ordirgl
Hello all, I have been using the function ordirgl to plot 3D dynamic
ordinations. The ordirgl function works just fine. IN fact, I was even
able to write a function that allows me to identify points in the 3D plot:
identify.rgl<-function(env_var,ord,dim1,dim2,dim3)
{
tmp<-select3d(button="left")
tmp.keep<-tmp(ord[,dim1],ord[,dim2],ord[,dim3])
2011 Jul 29
2
change pch in 3dplot, export graph
Hello I was wondering if anyone has been able to change the pch value for
points in 3dplot()? I am able to change point colors just not symbol types.
I have included a portion of my code below. I realize this won't work
outside of my script, but thought, maybe there is something obvious that I
am doing wrong. Also is it possible to utilize the interactive feature of
3dplot in a
2009 Feb 16
1
Help with rgl
Hi,
I don't know much about the RGL package, and I have read the
documentation and tried some parameters, with no luck... I would like
to generate a movie from a 3D object (code below), where the vortex A
is closer to the observer, and then the object rotates and the B
vortex gets closer. I would like to capture this movie to a file.
By the way, I am not being able to insert unicode text