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I can't find a commande to solve an implicit nonlinear equation. Does it exist please ?

Hi, I'm using the density() command for a given vector x and I would like to know how to get the estimated value of the density for each element of the vector x instead of values corresponding to points...

Hi everyone, I need some help to produce a random bistochastic matrix, that is a squared matrix of positive real numbers e_ij, with sum(e_i)=1 and sum(e_j)=1. Thanks Florent Bresson ___________________________________________________________________________ Demandez ? ceux qui savent...

I have to calculate some formula like: gamma(x)/(gamma(x+y) and I observed that for relatively big values of x, R returns infinity and so cannot compute the formula. Is it possible to force R to give the...

Dear R users, I would like to draw a plot with a custom scale for the axis. More precisely, instead of plotting y on x, I want to plot y on a monotone function of x (for instance a*x...

I'm dealing with a matrix like : "x" "y" "z" [1,] 2 4 1 [2,] 6 1 2 ... [n,] 7 3 1 For each row I would like to know the header of the column which corresponds to the minimum...

Please, I would like to generate a random bistochastic matrix, that is a squared matrix of non-negative numbers with each row and each column sum to 1, for example : .2 .3 .5 .6 .3 .1 .2 .4 .4 I...

Hi, I have to use a loop to perform a quite computer intensive estimation and I would like to know the progress of the loop during the process. I tried to include something like print(paste(k,date(),sep=" : ")) where...

I'm trying to run a nls on a subset of a data.frame. In the subset, one observation is NA. So I drop the observation but when I ask for : >sm <- nls(machin$revcum ~ Lc.singh(machin$popcum,p...

I' m trying to compute weighted mean on different groups but it only returns NA. If I use the following data.frame truc: x y w 1 1 1 1 2 2 1 3 1 1 4 2 0 2...

Hi, I've got a very simple problem but cannot find the solution. I'm using two data frames (say X and Y) and I want to get a subset of one according to the different levels of a variable...

Dear R-users, I would like to apply a function (more precisely sd()) over the third dimension of a three-dimension array. The function apply would be interesting but the chosen function can only be applied on the rows and...

I have to estimate the following model for several group of observations : y(1-y) = p[1]*(x^2-y) + p[2]*y*(x-1) + p[3]*(x-y) with constraints : p[1]+p[3] >= 1 p[1]+p[2...

I have succeded in defining the cdf of the generalized beta of the second kind, eg. pgbeta2 <- function(quint,b,a,p1,p2) { integrate(function(x) {exp(log(a)+(a*p1-1)*log(x)-(a*p1)*log(b)-log(beta...

I have defined a function to compute the value of a beta distribution of the second kind (the existing beta distribution of th stats package is the beta distribution of the first kind). It works perfectly for a single value...

I have to compute some standard errors using the delta method and so have to use the command "numericDeriv" to get the desired gradient. Befor using it on my complicated function, I've done a try with a simple exemple...

Dear R-users, I'm facing a problem with the import of data in R. I have a sav file that, I presume, uses some Arabic encoding (but I don't know which one) and I would like to read...

Maybe I do not explain well what I would like to do. I do not want to change the labels of the axis, but the scale. What I want is a general procedure for changing the scale. Its like using...

Yes, you're right. In fact, it's just an adaptation of a matlab command and the author advises using N^4 replications that's why it's the default in the function. The bistochastic matrix is not my subject...

Effectively, it's much better thanks --- Prof Brian Ripley <ripley at stats.ox.ac.uk> a ??crit??: > On Wed, 16 Nov 2005, Florent Bresson wrote: > > > I have to compute some standard errors using the > delta > > method and so have to...