Displaying 20 results from an estimated 1000 matches similar to: "binding rows from different matrices"
2008 Sep 10
1
Computation of contour values - Speeding up computation
Dear R useRs,
i have the following code to compute values needed for a contour plot
############################################################
"myContour" <- function(a, b, plist, veca, vecb, dim)
{
tmpb <- seq(0.5 * b, 1.5 * b, length=dim)
tmpa <- seq(0.5 * a, 1.5 * a, length=dim)
z <- matrix(0, nrow=dim, ncol=dim)
for(i in 1:dim)
{
for(j in 1:dim)
2007 Jun 12
0
[PATCH] Combined checkFTB and capDirection into one checkOrientation function.
---
include/cube.h | 18 +++------
plugins/cube.c | 120 +++++++++++++++++--------------------------------------
2 files changed, 43 insertions(+), 95 deletions(-)
diff --git a/include/cube.h b/include/cube.h
index 0a87626..293bad1 100644
--- a/include/cube.h
+++ b/include/cube.h
@@ -87,16 +87,11 @@ typedef void (*CubePaintInsideProc) (CompScreen *s,
CompOutput *output,
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:
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 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 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
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
2011 Nov 17
3
.Call in R
Hi R developers,
I am new to this forum and hope someone can help me with .Call in R.
Greatly appreciate any help!
Say, I have a vector called "vecA" of length 10000, I generate a vector
called "vecR" with elements randomly generated from Uniform[0,1]. Both vecA
and vecR are of double type. I want to replace elements vecA by elements in
vecR only if sum of elements in
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
2004 Oct 01
1
cumsum over a list or an array
Hello list,
my question is related to svd of a matrix:
b=matrix(rnorm(50),10,5)
mysvd=svd(b)
I would like to compute each xi where xi = di* ui %*% t(vi). I do it by :
xlist=sapply(1:ncol(b), function(x1,y)
y$d[x1]*y$u[,x1]%*%t(y$v[,x1]),y=mysvd,simplify=F) # result is a list
xarray=array(sapply(1:ncol(b), function(x1,y)
y$d[x1]*y$u[,x1]%*%t(y$v[,x1]),y=mysvd),c(nrow(b),ncol(b),ncol(b))) #
2004 Feb 25
2
writing polygons/segments to shapefiles (.shp) or other ArCGIS compatible file
I am not sure a previous e-mail reached the list (no mail aknowledgement from R-boundle etc.). The question was how to write polygon
or segment coordinates into a shapefile set or any other ArcGIS supported format. The library shapefiles seems to do something but
the documentation is a bit beyond of my mind.... and I cannot get the meaning of the functions write**** and its application to the
case
2004 Jan 01
1
ade4
Dear All,
I am using the scatter.dudi finction in the 'ade4' package to produce
correspondence analysis (nice) plots.
I do not seem to figure out how to plot the raw coordinates only -- or column
coordinates only. I would appreciate any help in doing that.
Here is the example I am following -- from the package.
data(banque)
> banque.acm <- dudi.acm(banque, scann = FALSE, nf =
2004 Mar 16
2
bray-curtis?
Does R have a function to calculate Bray-Curtis distance measures, which is
probably one of the most frequently used and recommended dissimilarity
measures in ecology? It isn't mentioned in dist().
2004 Mar 22
1
Débutant R
Bonjour à tous,
Je débute dans l'utilisation de R, et suis à la recherche de toute piste me permettant l'introduction à ce logiciel.
J'ai pour le moment la fiche d'Emmanuel Paradis: "R pour les débutants", mais j'aimerais savoir où je peut trouver
d'autres documentations notamment pour le traitement statistique de données (Anova, modèle linéaire et
modèle
2004 Apr 29
1
problem with pca
Hello
I have some kind of problem with R.
I want to do a pca (I work on R and ade4 library) but R doesn't wan to
realize my pca because of my data:
I have some binary variable (presence/absence of birds, hole, vegetals...)
and metric variable (cliff 's size...) and each time I have an error message
because of the mix of the 2 type of variable.
So, what can I do?
Famille SALMON
2004 Dec 08
2
Clustering in R
Is there a command to get cluster criterion for the cluster methods? SAS has its criterion, but I prefer to do it in R. If there is not a command is there code to produce criteria to choose the number of clusters?
Adrian Katschke
Statistics Grad Student
University of Nebraska-Lincoln
[[alternative HTML version deleted]]
2004 Dec 31
3
Citation
Does anyone know R is to be cited in a publication? I've looked everywhere
on the website and cannot find this.
Thanks,
Heather
--
Heather Maughan
Department of Ecology and Evolutionary Biology
Biosciences West 310
University of Arizona
Tucson, AZ 85701
Phone: 520-626-5108
Fax: 520-621-9190
hmaughan at u.arizona.edu
2004 Mar 09
1
Package cclust error
Hello, here is my problem,
After looking at the mail archives, I found a
description of the error I get when I use this
package.
At first I even tought that they were showing how to solve it.
But the thing is that by saying "the programmer
forgot drop=FALSE" doesn't show me how I should
get rid of the problem
I have looked inside the package very quickly and
I found three
2004 Feb 02
3
ordering and plotting question
Hi,
I am trying to plot several rows out of a list of thousands. I have 40
columns, and about 16,000 rows with the following Df structure.
ID X01 X02 X03..X40
AI456 45 64 23...
AI943 14 3 45 ..
AI278 78 12 68..
BW768 -2 -7 34..
...
My question is, I have a list of 100 IDs generated elsewhere
(Df-"Ofinterest"), I would like to plot the 100 IDs from that data
frame over the 40 columns