similar to: Adding a color bar to image

Hi! Some weeks ago I discovered R. Now, I have a somewhat complicated task and am not sure whether R is the right tool to solve it. I got data of several series or measurements where I have to find the two inflection points. I did a linear regression (with ^2 and ^3 arguments), the problem there was that I had to look only at a very narrow band of measurement in order to get the

Dear Users, I use Sgeostat to calculate co variogram (function est.variogram with two variables). If i inverse the 2 variables in the functions, the co variogram change! Normaly it is symmetric, isn't it? Someone could me explain why, or give me an idea to calculate co variogram in a easy way... Thanks in advance Laurent ps : sorry for my english Laurent William Dubroca Centre de

Hello, I discovered SAGA, an interesting free GIS, a few days ago and now, I would like to use it from within R 2.6.2 using the RSAGA package. I read the documentation for this package and thought that I understood it correctly for trying to call some of the SAGA modules. For getting the information on the usage of and arguments required by the SAGA command line "Import Binary Raw

I have to solve a clustering problem. My first step is to determinate the number of clusters, that's why I 'm using the Calinski index ( [tr(b)/(k-1)]/[tr(w)/(k-1)] ) which i try to maximize to have the best number of clusters. A function is already implemented in R to calculate this index : clustIndex(cl,x, index="calinski") where cl is the result of a clustering method ,

Hi R-users, I have to define a noise level function L and its energy in the various moment of the day by: if time is between 18:00:00 and 23:59:59 then L[j] <- L[j]+5 and W <- 10^((L+5)/10) if time is between 22:00:00 and 05:59:59 ==> L <- L+10 and W <- 10^((L+10)/10) else L=L and W = W Could someone help me to realize this function please? You will find my following

dear all, I would like to center and scale some columns of a data frame (these include NAs) according to the levels of an index (list of factors from the same data frame). I tried to code it using for loops but gave up. I guess there is a straightforward way to achieve this: any hint welcome! thanks a lot thomas -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-

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

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:

Recently, I have been working with some data that look like two overlapping gaussian distributions. I would like to either 1) determine the mean and SD for each of the two distributions OR 2) get some (bayesian ?) statistic that estimates how likely an observation is to belong to the left-hand or right-hand distribution In case I'm using the wrong language, my data looks something like

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

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

How to is possible this? > [root at lucatest ~]# ls -lid /var/log /var/log/ispconfig /var/log/ispconfig/httpd /var/log/ispconfig/httpd/prova.it /var/log/ispconfig/httpd/prova.it/test /var/www /var/www/clients /var/www/clients/client1 /var/www/clients/client1/web3 /var/www/clients/client1/web3/log /var/www/clients/client1/web3/log/test > 706 drwxr-xr-x. 15 root root 4096 29 mag 08:44

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

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

Hello, I would like to have any help with the function Kmeans of R.. I use this to do a classification of my data...I have chosen 12 classes but, I have always an error message: Error: empty cluster: try a better set of initial centers So, I don't understand the probleme with this function.. Thank you to help me!! All the Best Clothilde Clothilde Kussener CNRS - CEBC 79360 Villiers en bois

Hi, Does anyone know how to make the color of the lines all black when plotting groupedData with an outer factor: For example, library(nlme) plot(Dialyzer, outer=~QB, key=F) This generated colored curves in R.2.4.1. How to make all the curves black ? (or how to alter the color (type) of lines for the nlme groupedData plotting function in general?) Thanks Qiong

Hi, I have not been able to calculate residuals in the lme4 package. I've been trying the resid() function after I ran a GLMM with the lmer() function, but I get an error message that says "residuals are not inserted yet". I looked it up in the "help" history and I realized that several people have had this problem in the past, related to some bug in this function and

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 =

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().

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