Displaying 20 results from an estimated 2000 matches similar to: "R package to perform Horn's parallel analysis"
2005 Dec 14
1
CRAN task view: Multivariate
Hello,
I've assembled a Multivariate ctv (with a lot of help from Achim Zeleis,
who has now posted the view on CRAN).
I'd be grateful for comments regarding missing packages / functions.
Opinions on the organisation of the view would also be appreciated, as
well as having any errors pointed out. I've adopted a rather broad and
vague definition of "multivariate", which may
2004 Mar 24
7
binding vectors or matrix using their names
Hello list,
I have two vectors x and x2:
x=runif(10)
x2=runif(10)
and one vectors with their names :
my.names=c("x","x2")
I would like to cbind these two vectors using their names contained in the
vector my.names.
I can create a string with comma
ncomma=paste(my.names,collapse=",")
and now, I just need a function to transform this string into a adequate
2004 Sep 20
4
Multiple operations on list
Hello,
suppose I have a list with matrices:
a=list(x1=matrix(rnorm(10),5,2),x2=matrix(rnorm(10),5,2),x3=matrix(rnorm(10),5,2))
I want to compute for all combination of xi and xj (x1,x2 x1,x3 and x2,x3)
a value.
This value is given for the pair x1,x2 by trace(x1%*%t(x1)%*%x2%*%t(x2)) /
trace(x1%*%t(x1))*trace(x2%*%t(x2))
I know that product matrices t(xi)%*%xi can be obtained by:
2004 Feb 23
2
orthonormalization with weights
Hello List,
I would like to orthonormalize vectors contained in a matrix X taking into
account row weights (matrix diagonal D). ie, I want to obtain Z=XA with
t(Z)%*%D%*%Z=diag(1)
I can do the Gram-Schmidt orthogonalization with subsequent weighted
regressions. I know that in the case of uniform weights, qr can do the
trick. I wonder if there is a way to do it in the case of non uniform
2008 Apr 24
1
R and condor
Hello,
I would be extremely grateful if anyone is able to provide any (rather obscure) advice on using R with Condor. I think I'm following Xianhong Xie's instructions (R News 5(2) 13-15) correctly, but my job just stays held in the queue (for days / months). I've checked condor_status to make sure there are plenty of machines available, but can't see any way to attack the
2004 Dec 20
2
Producing "Editable" Graphs for PowerPoint
Hello,
(apologies, I'm not entirely sure whether this question is about R or my
limitations with PowerPoint). I've submitted a paper (which has been
accepted) but the journal now require me to submit graphs that are
"editable in PowerPoint". I would be grateful for suggestions as to
how I should do this.
The best route seems to be to copy-and-paste the figures from the
2003 Nov 04
2
real eigenvectors
Hello list,
Sorry, these questions are not directly linked to R.
If I consider an indefinte real matrix, I would like to know if the
symmetry of the matrix is sufficient to say that their eigenvectors are real ?
And what is the conditions to ensure that eigenvectors are real in the case
of an asymmetric matrix (if some conditions exist)?
Thanks in Advance,
St?phane DRAY
2004 Oct 22
4
Evaluate a function for various value of parameters
Hello list,
I have a problem ... and do not know how to solve it.
I would like create a function that estimate the quality of the fit of
different functions with different values of parameters.
This problem is related to the following one:
I would like to create a function "evaluatemyfunction" which evaluate a
function f for different values of parameters. For instance, if
2008 Apr 01
1
superimpose histogram on biplot
Hi all,
I've been trying to figure out how to superimpose a histogram on a
biplot that shows the relative contribution of each axis. I have
been using the NIPALS function (http://biomserv.univ-lyon1.fr/~dray/
files/softwares/nipals.R) to run principal component analyses. Here
is a toy example.
source("http://biomserv.univ-lyon1.fr/~dray/files/softwares/nipals.R")
2004 Jul 06
2
Generate a matrix Q satisfying t(Q)%*%Q=Z and XQ=W
Hello,
I have a question that is not directly related to R ... but I try to do it
in R ;-) :
I would like to generate a matrix Q satisfying (for a given Z, X and W) the
two following conditions:
t(Q)%*%Q=Z (1)
XQ=W (2)
where:
Q is m rows and r columns
X is p rows and m columns
D is p rows and r columns
C is r rows and r columns
with m>p,r
e.g:
m=6,
p=2
r=3
2004 Mar 31
3
scan seems to modify the data
Hello list,
I have used scan function to import data into R. I have done some analysis
and find strange results. I have found my problem : when importing data
with scan, this can slightly modify the data :
> write(c(0.251,3.399,-0.481,0.266),"essai.txt")
> scan("essai.txt")
Read 4 items
[1] 0.251 3.399 -0.481 0.266
> print(scan("essai.txt"),17)
Read
2005 Feb 19
16
Snom phone hint exten question
Hi,
I am sorry to be asking this but the wiki is down and has been for a
couple of days and I need to get this working before Monday to get my
live system setup.
Trying to get the Snom 190's and soon to arrive 3com 3102's to use the
function keys and for the life of me I can't work it out from the
conversations on the archive what I am going exactly wrong here?
The snom 190 with
2004 Jul 09
3
analytic solution for equation
Hello,
I have search on R website but do not find any solution.
I would like to know if R has some functionalities to produce analytical results
of equation. or more generally if it contains some functions to simplify equation.
For example:
I would like to obtain x1 from:
x1+x2=8 (x1=8-x2)
x1^2+x2=8 (x1=sqrt(8-x2))
Is is possible in R ? if not, do you know a (free) software that could do the
2006 Sep 27
1
Testing the equality of correlations
Dear All,
I wonder if there is any implemented statistical test in R to test the equality between many correlations. As an example, let X1, X2, X3 X4 be four random variables. let
Phi(X1,X2) , Phi(X1,X3) and Phi(X1,X4) be the corresponding correlations.
How to test Phi(X1,X2) = Phi(X1,X3) = P(X1,X4)?
Many thanks in advance,
Bernard
2005 Jun 28
1
enhanced multidimensional scaling?
Dear R list
Would anyone be able to tell me whether it is possible to do "enhanced
multidimensional scaling" (enhanced MDS) in R? In other words, something that
goes beyond "cmdscale" by iteratively improving the fit between observed
dissimilarities and inter-object distances, using the KYST algorithm
(Kruskal, 1964).
I have found several implementations of non-metric MDS
2007 Nov 16
1
Efficient way to compute power of a sparse matrix
Dear all,
I would like to compute power of a square non symmetric matrix. This is
a part of a simulation study. Matrices are quite large (e.g., 900 by
900), and contains many 0 (more than 99 %). I have try the function
mtx.exp of the Biodem package:
library(Biodem)
m <- matrix(0, 900, 900)
i <- sample(1:900, 3000, replace = T)
j <- sample(1:900, 3000, replace = T)
for(x in 1:3000)
2004 Jun 29
2
binding rows from different matrices
Hello list,
I have 3 matrices with same dimension :
> veca=matrix(1:25,5,5)
> vecb=matrix(letters[1:25],5,5)
> vecc=matrix(LETTERS[1:25],5,5)
I would like to obtain a new matrix composed by alternating rows of these
different matrices (row 1 of mat 1, row 1 of mat 2, row 1 of mat 3, row 2
of mat 1.....)
I have found a solution to do it but it is not very pretty and I wonder if
I
2002 Jun 11
1
NT user name doesn't match unix username when winbindd is runnin g
Samba team,
I posted the following message on May 30 to comp.protocols.smb, but no one
has responded to the posting as of yet, so I thought I'd try this email
list.
We are testing winbind and security=domain to authenticate NT users on
our UNIX box in samba (v2.2.3a). Winbind is working correctly. Wbinfo
shows
users as domainname+username (we are using "+" as the
2001 May 29
3
geary statistics
Hello,
i' m looking for a function to compute geary statistic for spatial correlation.
Thanks.
--
St?phane DRAY
---------------------------------------------------------------
Biom?trie et Biologie ?volutive - Equipe "?cologie Statistique"
Universite Lyon 1 - Bat 711 - 69622 Villeurbanne CEDEX - France
Tel : 04 72 43 27 56 Fax : 04 78 89 27 19
04 72 43 27 57 E-mail
2003 Apr 21
2
randomForest crash?
I am attempting to use randomForests to look for interesting genes in
microarray data with 216genes, 2 classes and 52 samples. My data.frame
is 52x217 with the last column, V217 being the class(1 or 2).
When I try
lung.rf <- randomForest(V217 ~ ., data=tlSA216cda, importance=
TRUE, proximity = TRUE)
the GUI crashes.
I am running R-1.6.2 under windo$e98, and most