Displaying 20 results from an estimated 100 matches similar to: "Math Expression in 3D Plots"
2003 Apr 18
1
Help with nlme--freq weights, logit model, and more
Below you will find the output from a failed multi-level model run. I am
trying to estimate the following model:
Pr(PLFP=1)= logistic regression ->
B1_j * bm + B2_j * wm + B3_j bf + B4_j wf + B5 yrsed+ B6 age+ B7 age^2+e_ij
B1_j = G01 + G11 bmxd + d1
B2_j = G02 + G12 wmxd + d2
B3_j = G03 + G13 bfxd + d3
B4_j = G04 + G14 wfxd + d4
d1-d4 freely correlated
Note that there is no
2009 Oct 14
1
TFTP prefix in pxelinux.0 ?
Hello,
I wonder if it is possible to change pxelinux.0's tftp prefix...
I want to setup a repository like that:
|-- dist1
| |-- pxelinux.cfg
| | `-- default
| `-- pxelinux.0
|-- dist2
| |-- pxelinux.cfg
| | `-- default
| `-- pxelinux.0
|-- pxelinux.cfg
| |-- default
| `-- menu.c32
`-- pxelinux.0
The file /pxelinux.cfg/default would contain something like that:
>
2006 Mar 08
1
function gdist, dist and vegdist in mvpart
Dear R community,
I am analyzing plant communities with the function mvpart, using a
dissimilarit matrix as input. The matrix is calculated with the funtion
gdist.
fit <- mvpart(gdist (ba12[,18:29], meth="maximum", full=TRUE,
sq=F) ~ beers + slope_dem + elev_dem+ plc_dem + pr_curv+
+curv+max_depth+doc_rocks+ abandon+land_use+ca_old,
data=ba12, xv="p")
This
2004 Oct 01
3
Reading multiple files into R
I want to read data from a number of files into R.
Reading individual files one by one requires writing enormous amount of
code that will look something like the following.
****************
maptools:::dbf.read("wb-01vc.dbf")->dist1
maptools:::dbf.read("wb-02vc.dbf")->dist2
maptools:::dbf.read("wb-03vc.dbf")->dist3
2011 Aug 09
1
rgl how to plot a cylinder like arrow3d?
Dear List,
I'm trying to draw vector in XYZ with rgl under use of a cylinder3d.
Therefore I scale and rotate a basis-cylinder).
However, somehow the rotation is wrong as
verified by overplotting arrow3d().
Where is my mistake?
library(heplots)
library(rgl)
# ... 2 vectors
data=data.frame(row.names=c('X','Y','Z'), x1=c(2,1,5),y=c(4,3,2))
2013 Mar 10
1
Error with grad() for numerical differential of a function
Hello everyone,
I have programmed a function and, among other things, it has to compute the differential of a function. I have been using the function grad() and I have programmed some simulated studies. I have testes with 72,576 different combinations of the initial values and now I got an error in only 4 situations.
The error comes from the function grad() and I don't understand why. This
2006 Oct 11
1
Bug in stepAIC?
Hi,
First of all, thanks for the great work on R in general, and MASS in
particular. It's been a life saver for me many times.
However, I think I've discovered a bug. It seems that, when I use
weights during an initial least-squares regression fit, and later try to
add terms using stepAIC(), it uses the weights when looking to remove
terms, but not when looking to add them:
2007 May 29
1
rgl.postscript
Hi,
I am having an issue when creating a postscript file from RGL window. It
seems to cut off some of the axis labels. Here is the code I am using.
I created a 3D plot using RGL_0.71 with R 2.5 on Windows XP.
z1<-c(5,4,1,4.5,2,3,2,1,1)
z2<-c(6,8,7,7.5,5,3.5,4,1,1)
z3<-c(3,2,4,7,3,4.5,6,2,3)
x1<-seq(1,9)
x2<-seq(1,9)
x3<-seq(10,18)
y1<-seq(8,0)
y2<--1*y1
2005 Oct 06
1
Compare two distance matrices
Hi all,
I am trying to compare two distance matrices with R. I would like to
create a XY plot of these matrices and do some linear regression on
it. But, I am a bit new to R, so i have a few questions (I searched in
the documentation with no success).
The first problem is loading a distance matrix into R. This matrix is
the output of a the Phylip program Protdist and lookes like this:
5
2013 Jun 22
1
metaMDS Error, Nan similar or negative values
H
ello R-experts,
I want to do ordination plots using vegan metaMDS.
I have a where many cells have zero values.
Data structure:
X[1:10,1:14]
Height.1 Height.2 Height.3 Height.4 Height.5 Height.6 Height.7
Height.8 Height.9 Height.10 Height.11 Height.12 Height.13
D30I1A 46 0 0 0 0 0 0
0 0 0 39 0 98
D30I1B
2011 Sep 09
1
rgl: axis/viewport/box problems in persp3d()
Dear expeRts,
I am a new user of rgl, below is my first trial to plot a simple function in 3d.
I managed to put the axes in the right locations, but:
(1) The xlab, ylab, and zlab arguments are ignored; how can I put in axes labels?
(2) Since I removed the axes in persp3d() the viewport is too small; is it possible
to keep the size of the viewport?
(3) The box is not correctly drawn, there
2014 Jul 04
3
script de anomalias
Tengo una consulta, alguien tiene algun script en R para hacer graficos de
anomalias estandarizadas (precipitacion, temperatura, etc) y que me permita
pintar de rojo anomalias positivas y azules las negativas,
Muchas gracias de antemano
--
Luis Alfonso LOPEZ ALVAREZ
MSc- Meteorologia - Ing. Sistemas
PROFESIONAL ESPECIALIZADO (E)
METEOROLOGO - IDEAM
e-mail: llopez@ideam.gov.co
2012 Oct 01
6
nlme: spatial autocorrelation on a sphere
I have spatial data on a sphere (the Earth) for which I would like to run an gls model assuming that the errors are autcorrelated, i.e. including a corSpatial correlation in the model specification.
In this case the distance metric should be calculated on the sphere, therefore metric = "euclidean" in (for example) corSpher would be incorrect.
I would be grateful for help on how to
2005 Sep 30
0
p-value for non-linear variable in overdispersed glm()
Dear all,
I am fitting an nonlinear glm() using optim() by first minimising
glm(resp~ var1 + var2, family=binomial, data=data)$deviance
where var1= exp(-a1*dist1), and var2= exp(-a2*dist2), where a1 and a2 are
parameters and dist1 and dist2 are independent variables.
Next, I calculate the value of var1 (and var2) by plugging in the value of
al1 (and al2) that minimises deviance,
and fit
2001 Oct 22
2
OT: compare several graphs
Hi all,
this is OT, but maybe someone can give me a clue. I've got data from eye
tracker experiments (750 data points). These figures show how the data
lock like
|** * ***** |*** ******
| ** **** | * *
| | * *
| | *
|-------------- |---------------
Y axes display velocity, x axes display time, * are the data points.
2010 May 11
2
question about R
Hi,
At each iteration in my program,I need to generate tree vectors,X1,X2,X3,
from exponential distribution with parameters a1,a2,a3. Can you help me
please how can I do it such that it take a little time?
thank you
khazaei
2007 Jun 05
2
biplot package
Dears,
I've been learning biplot (Gabriel, 1971) and I found the function 'biplot', inside of the package 'stats',
useful but, a bit limited.
So, I'm thinking to start a colaborative package to enhance this methods to other multivariate methods. In this
way, I would like to start it, making public a new function (biplot.pca, still in development, but running)
that make
2004 Feb 23
2
plot(my.procrustes.model) from library {vegan}
Dear All,
I would like to ask how to customize the graph corresponding to a
procrustes analysis.
I have to distance matrices, that I transform to two set of coordinates
by means of muti dimensional scaling:
library(mva)
c1<-cmdscale(mat.dist1)
c2<-cmdscale(mat.dist2)
I vant to rotate c2 on c1, and I use the "procrustes" analysis from the
{vegan} library.
library(vegan)
2003 Nov 27
2
Getting rid of loops?
I wrote a function to calculate cosine distances between rows of a matrix.
It uses two loops and is slow. Any suggestions to speed this up? Thanks in
advance.
theta.dist <- function(x){
res <- matrix(NA, nrow(x), nrow(x))
for (i in 1:nrow(x)){
for(j in 1:nrow(x)){
if (i > j)
res[i, j] <- res[j, i]
else {
v1 <- x[i,]
v2 <- x[j,]
2006 Nov 30
3
newbie: new_data_frame <- selected set of rows
Hello,
this is probably trivial but I failed to find this
particular snippet of code.
What I got:
my_dataframe (contains say a 40k rows and 4 columns)
distances (vector with euclidean distances between a
query vector and each of the rows of my_dataframe)
What I do:
after scaling data my_dataframe I calculate distances.
order them then extract top five hits
my_dataframe <-