Displaying 20 results from an estimated 1000 matches similar to: "random uniform sample of points on an ellipsoid (e.g. WGS84)"
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
2006 Oct 18
1
conversion of LL coordenates to UTM problems (ED50-WGS84 format)
Hi R-Users,
I have plotted a region whose polygon coordinates are given in shp format ED50 UTM (zone=30) ) using "readShapePoly" in library(maptools).
Now I need to plot a set of points in that region (my.dataframe, with X and Y geographic coordinates), which have been read using GPS in Longitud-Latitud form (using WGS84 system), so I first need to convert these Longitud-Latitud data
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 Apr 03
1
which points within an ellipsoid? Sorting data in 3d
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
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
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
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
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
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
2002 May 01
1
"normal probability plot" with a percentile scale?
I'd like to generate some plots like you'd see on the old "normal
probability graph paper", like the first plot in:
<http://www.itl.nist.gov/div898/handbook/eda/section3/normprpl.htm>
except the horizontal scale would have 1%, 5%, 25%, 50%, 75%, 95%,
99%, or similar quantiles, with associated tick/grid lines. [still
hunting around for a good example...] something like
2002 Jul 06
2
cross-platform code: windows or gnu/linux?
I am writing some R code that generates some figures. I am primarily
developing on GNU/Linux, but will ultimately run the code on Windows
in order to get WMF files I can integrate in an existing document.
The win.metafile() function, of course, doesn't exist in the GNU/Linux
version of R. I am contemplating writing an abstraction layer that
runs the right thing, but I need to know how the
2002 May 02
2
coercing "numeric" components of data frame to "factor" or "ordered"?
I am getting ready to load a bunch of data into R. The data is all
numeric, but some of the numbers are integer codes representing
non-numeric semantics. What is the best way to "fix" the data frames
so that these compenents are recognized as "factors" or "ordered", as
appropriate?
Can I "assign" to some attribute of the data frame component, like the
2008 May 26
1
[PATCH] virtio_rng: dont use vmalloced addresses for virtio
If virtio_rng is build as a module, random_data is an address in vmalloc
space. As virtio expects guest real addresses, this can cause any kind of
funny behaviour, so lets allocate random_data dynamically with kmalloc.
Signed-off-by: Christian Borntraeger <borntraeger at de.ibm.com>
---
drivers/char/hw_random/virtio-rng.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
2008 May 26
1
[PATCH] virtio_rng: dont use vmalloced addresses for virtio
If virtio_rng is build as a module, random_data is an address in vmalloc
space. As virtio expects guest real addresses, this can cause any kind of
funny behaviour, so lets allocate random_data dynamically with kmalloc.
Signed-off-by: Christian Borntraeger <borntraeger at de.ibm.com>
---
drivers/char/hw_random/virtio-rng.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
2003 Oct 28
2
formula parsing, using parts ...
I am writing a little abstraction for a series of tests. For example,
I am running an anova and kruskal.test on a one-factor model. That
isn't a particular problem, I have an interface like:
my.function <- function(model,data) {
print(deparse(substitute(data)))
a <- anova(lm(formula,data))
print(a)
if(a$"Pr(>F)"[1] < 0.05) {
pairwise.t.test(???)
}
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
2002 May 10
1
qqnorm() with weighted data?
I've got a set of data that are weighted by a largish integer (ranging
from about 50K to 1.5 million). I'd like to plot CDF's for this data
taking into account the weighting. What do you recommend?
Thanks!
--
Russell Senior ``The two chiefs turned to each other.
seniorr at aracnet.com Bellison uncorked a flood of horrible
2003 Dec 20
1
why not link devices with --link-dest option?
I notice that devices are not hardlinked when using the --link-dest
option, for instance:
rsync -aH --link-dest=../bar/ foo/ baz/
When foo/zero is a device, baz/zero is not a hardlink to bar/zero. How
come?
$ rsync --version
rsync version 2.5.6 protocol version 26
on linux 2.4.x
--
Russell Senior ``I have nine fingers; you have ten.''
seniorr@aracnet.com
2003 Sep 14
1
estimating quantiles from binned data
Suppose I have a set of binned data, counts exceeding a series of
arbitrary thresholds, a total N, a minimum and maximum, those sorts of
things. Is there a "standard" method for estimating arbitrary
quantiles from this?
My initial thought is that the counts and min/max give me solutions at
various points along the empirical cdf. As the data are roughly
log-normal, I thought maybe I
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