search for: polynome

Hello, I have 3 columns : a, b and a*b I would like to find the pair (a,b) so that a*b is the minimum but not from the points I measured but from the fit of the curve (I have more points that the ones given below but I fit only on this part because I know that the minimum a*b is in this interval). I thought doing it this way : - to fit a*b=f(a) abfit<-lm(ab ~ poly(a,8,raw=T)) - to use the

Merci beaucoup, Jean, for the bug report -- which I'm no "completeing" to R-bugs >>>>> "Jean" == Jean Coursol <coursol@cristal.math.u-psud.fr> >>>>> on Thu, 24 Jun 2004 15:22:37 +0200 (CEST) writes: Jean> I was exploring the polynom library with students: <and found a segmentation fault from parsing a long expression>

Dear R people: I am trying to download the package polynom to R version 1.0.1.1. on Windows. Here are my commands and output: > install.packages("polynom",lib="c:\rw1011\library",CRAN="http://www.r-project.org/src/contrib/") Error in start[k]:(start[k + 1] - 1) : NA/NaN argument In addition: Warning message: Download had nonzero exit status in:

hi there, can anyone help me on the topic of frag polynoms? i just heard of a friend of mine, that i could build in a functioon called fragpoly (he was talking of such a function in the 'stata' language) in order to improve my process of finding an optimal linear model. instead of trying a vast amount of transformed inputdata to find the best fit and then step backwards down to e.g.

Hi, I can not comprehend the linear fitting results of polynoms. For example, given the following data (representing y = x^2): > x <- 1:3 > y <- c(1, 4, 9) performing a linear fit > f <- lm(y ~ poly(x, 2)) gives weird coefficients: > coefficients(f) (Intercept) poly(x, 2)1 poly(x, 2)2 4.6666667 5.6568542 0.8164966 However the fitted() result makes sense: >

Something strange is happening with update.packages on my machine (Win2000, R-1.5.0 installed from binaries). Some of the packages (see below) keep getting updated every time. When I issue update.packages() I get this every time for the last few days (I think since I installed 1.5 and the packages but I am not sure). This happens with CRAN shown below and also with CRAN set to

Dear R-users, is there any package that allows for a division of two polynomials? Regards, M. Fischer Dr. Matthias Fischer Friedrich-Alexander-Universit?t Erlangen-N?rnberg Lehrstuhl f?r Statistik und ?konometrie Lange Gasse 20 90403 N?rnberg Telefon: 0911 / 5302-271 Telefax: 0911 / 5302-277 E-Mail: Matthias.Fischer at wiso.uni-erlangen.de

I've packaged Bill's polynom add-on for R (i.e., converted man pages and took care of TITLE and INDEX). Apart from the missing poly() everything should be fine ... The package can be found in the CRAN src/contrib area. I've also added it to the Debian ix86 r-contrib package. -k =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- r-devel mailing list --

Good day everyone, I want to use the Gram-Charlier series expansion to model some data. To do that, I need functions to: 1) Calculate 'n' moments from given data 2) Transform 'n' moments to 'n' central moments, or 3) Transform 'n' moments to 'n' cumulants 4) Calculate a number of Hermite polynomials Are there R-functions to do any of the above?

Any better (more efficient, built-in) ideas for computing coef[1]+coef[2]*x+coef[3]*x^2+ ... than polynom <- function(coef,x) { n <- length(coef) sum(coef*apply(matrix(c(rep(x,n),seq(0,n-1)),ncol=2),1,function(z)z[1]^z[2])) } ? Ben -- 318 Carr Hall bolker at zoo.ufl.edu Zoology Department, University of Florida http://www.zoo.ufl.edu/bolker

Please, I'm a beginner with the R language. I'm looking for a function to compute a Polynomfit for simple x-y Data. Who can help? Many Greetings E.A. Welge -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in the

I'm one of the many who is far more interested in the reason for the request than in the numerical method to use. The way I see it, the methodology of, say, polyroot() suffices in a mathematical sense. If your coefficients are mathematically exact (as opposed to measured values), the near-singularities and such don't really matter, assuming infinite precision math. So, what

From: jypuppy36@hotmail.com To: r-help-bounces@r-project.org Subject: R programing help-newton iterations for the square root Date: Tue, 7 Dec 2010 12:00:01 -0800 NEWTON ITERATIONS FOR THE SQUARE ROOT Newton iterations to find the root of a real valued function f , i.e. a number x for which f (x) = 0, are of the form Example. To find the square root of a positive number y we can use

Hello, I'm trying to fit some points with a 8-degrees polynom (result of lm is stored in pfit). In most of the case, it is ok but for some others, some coefficients are "NA". I don't really understand the meaning of these "NA". And the problem is that I can't perform a derivation (pderiv<-as.function((deriv(polynomial(pfit$coefficients))))) on pfit due to the

Dear all, I'm looking for how can I estimate a linear model with ar(ma) errors : y(t)=a*X(t)+e(t) with P(B)e(t)=Q(B)u(t) where u is a white noise and P, Q are some polynomes. Could you help me ? Gr?gory Benmenzer

Hi, I would like to get the coefficient of polynomial expansion. For example, (1+ x)^2 = 1 + 2x + x^2, and the coefficients are 1, 2 and 1. (1 + x + x^2)^3 = 1 + 3*x + 6*x^2 + 7*x^3 + 6*x^4 + 3*x^5 + x^6, and the coefficients are 1, 3, 6, 7, 6, 3, and 1. I know that we can use polynom library. Is there any other way to do it without loading a library. Thanks a lot for your help. Peter

Full_Name: Jens Keienburg Version: 2.3.0 OS: Windows XP Submission from: (NULL) (193.174.53.122) I used the function lm() to calculate the coefficients of a polynome. If I used the function poly(t,2) to denote a polynome of form 1 + x + x^2, the coefficients are wrong. I appended an excerpt below: > t=1:100 > p=-20 - 10 * t + 2 * t^2 > p [1] -28 -32 -32 -28 -20 -8 8 28 52 80 112 148 188 232 280 332 388 448...

Hi, I am trying to estimate an ARIMA model in the case where I have some specific knowledge about the coefficients that should be included in the model. Take a classical ARIMA (or even ARMA) model: P(B) X(t) = Q(B) epsilon(t), where X(t) is the data, epsilon is a white noise, B is the backward operator and P and Q are some polynoms. Additionally, assume that you know in advance how P and Q

Awaiting some suggestion. Was my question not very understandable? Please let me know how can I offer more elaborate clarification. Additionally, I would like to solve the determinant of "p1" for the values of "z" (I am working with some multivariate time series modelling). When I use det() function, it am getting error that, that function is not for objects with class

Hi, I would like to get the coefficients of x^0, x^1, x^2, . , x^6 from expansion of (1+x+x^2)^3. The result should be 1, 3, 6, 7, 6, 3, 1; How can I calculate in R? You help will be greatly appreciated. Peter [[alternative HTML version deleted]]