search for: legendre

Hi All, I need to evaluate a series expansion using Legendre polynomials. Using the 'orthopolinom' package I can get a list of the first n Legendre polynomials as character strings. > library(orthopolynom) > l<-legendre.polynomials(4) > l [[1]] 1 [[2]] x [[3]] -0.5 + 1.5*x^2 [[4]] -1.5*x + 2.5*x^3 [[5]] 0.375 - 3.75*x^2 + 4.375*x^4...

Hello everyone, I would like to find out if there are already implemented function for legendre polynomials. I tried google but returns nothing. How do you suggest me to search for that? Regards Alex [[alternative HTML version deleted]]

I stumbled across this link and was wondering if this has any relation to the R project. http://www.fas.umontreal.ca/BIOL/Casgrain/en/labo/R/index.html -jennifer ----------------------------------- J. Steinbachs, Ph.D. Computational Biologist http://compbiology.org ----------------------------------- -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing

...tegrate(function(y) { sapply(y, function(y) { integrate(function(x) x*y, 0, 1)$value }) }, 0, 1) but I would like to use Gauss Quadrature to do it. I have written the following code (using R's statmod package) which works fine for one integral but it doesn't work for a double one: # Gauss-Legendre abscissas nodes <- gauss.quad.prob(25,dist="uniform",l=-1,u=1)$nodes # and weights weights <- gauss.quad.prob(25,dist="uniform",l=-1,u=1)$weights weights <- weights*2 # Approximate integral of f from a to b using Gauss-Legendre gauss_legendre<-function(f,a,b,nodes,...

Dear R-Help Does "The R Package for Multivariate and Spatial Analysis Version 4.0 (Casgrain and Legendre, 2001)" exist on CRAN and under what name? It supposedly has a chronological clustering program ,CHRONO, that I would like to use. Alternatively, I would ask if there is a R based program that performs chronological clustering? Thanks Alex Alex Hanke Department of Fisheries and Oceans St....

Hola a todos, Por casualidad alguno que tenga el libro de Legendre de Numerical Ecology with R sabe dónde o cómo bajar los data sets que se mencionan para seguir los ejemplos? Muchas gracias por su ayuda! ---- *Angela Andrea Camargo Sanabria* Estudiante Doctorado en Ciencias Biológicas Laboratorio de Ecología de poblaciones y comunidades tropicales Centro de Inve...

Pierre Legendre has developed a beta version of a new redundancy analysis package called RdaTest that is available on his web page at the Universit® de Montréal. The test example that is included with the package is based on the example provided in his book (Numerical Ecology, Chapter 11 (Legendre & Legendre...

Dear list, This is quite a specific question requiring the package orthopolynom. This package provides a nice implementation of the Legendre polynomials, however I need the associated Legendre polynomial which can be readily expressed in terms of the mth order derivative of the corresponding Legendre polynomial. (For the curious, I'm trying to calculate spherical harmonics [*]). Because legendre.polynomials(l) returns a lis...

...lyse genetic distance data ( provided as a dist object calculated using dist.genpop in package adegenet) with geographic distance partialled out ( provided as a distance object using dist function in veganthis method is attempting to follow the method used by Geffen et al 2004 as suggested by Legendre and . FORTIN (2010). I cannot see how to introduce the Conditioning ( partialled) second dist matrix. as you can see from the code snippet below, the two dist objects are of the same dimensions. - I get an error using capscale: Error in qr.fitted(Q, Xbar) : 'qr'...

...> know if there's a reason other than blind-spec-compliance. Pointers? > > Regards, > > --dkg One reason the generator of the full (Z/pZ)* is avoided is because knowledge of g^a and g^b (both known to Mallory) leaks information about the shared secret g^(ab) via their legendre symbols. This is particularly troublesome in the context of El Gamal. I don't have a reference to recommend off-hand but you might want to google for "decisional diffie hellman assumption". --mancha -------------- next part -------------- A non-text attachment was scrubbed... Nam...

Hi, I'm trying to find out what threshold of indicator value in labadsv should be used to accept a specie as an indicator one? So far I assumed that indval=0.5 is high enough to avoid any mistakes but it was based only in my intuition. I'd be greatful for any advise best regards Agnieszka

Dear all, Has anyone written R code for partial Mantel Tests- as described for instance in Legtendre & Legendre (1998) ? In other words, in a community ecology analysis, I would like to calculate the correlation between two dissimilarity matrices, controlling for a third distance matrix representing geographical distances between sites. Thanks! Christophe Bouget Biodiversité et gestion des forêts de plaine...

Hi every body: I need some help with kendall.global. The example in the manual seems not working well, and cannot used with my data, always the same error. data(mite) > mite.hel <- decostand(mite, "hel") > > # Reproduce the results shown in Table 2 of Legendre (2005), a single group > mite.small <- mite.hel[c(4,9,14,22,31,34,45,53,61,69),c(13:15,23)] > kendall.global(mite.small) Errore in FUN(newX[, i], ...) : .Random.seed is not an integer vector but of type 'list' > kendall.post(mite.small, mult="holm") Errore in sample...

Hi, I hope someone knows the answer to this or has a real good reference about it (I am using Legendre & Legendre, Numerical Ecology, 1998).... My data is a data.frame with locations as rows and vegetation assemblages / species as columns. I've done a PCA, a correspondance analysis (CA) using ca in ca package and a detrended correspondance analysis (DCA) using decorana from vegan package. As...

Does anybody know of any R functions to perform chronological clustering as explained in: Legendre, P., S. Dallot & L. Legendre. 1985. Succession of species within a community: chronological clustering, with applications to marine and freshwater zooplankton. American Naturalist 125: 257-288. http://www.fas.umontreal.ca/BIOL/legendre/reprints/succession_of_species.pdf Thanks, Angel

Hi, I'd like to perform Dufrene-Legendre Indicator Species Analysis for a multivariate regression tree. However I have problems with arguments of duleg(veg,class,numitr=1000)function. How to obtain a vector of numeric class memberships for samples, or a classification object returned from mvpart? thanks in advance -- Best regards, Agn...

...The orthogonal polynomial is summarized by the coefficients, which can be used to evaluate it via the three-term recursion given in Kennedy & Gentle (1980, pp. 343–4), and used in the predict part of the code. My question: which type of orthogonal polynomials are used by this function? Hrmite, legendre.. TIA Giovanni [[alternative HTML version deleted]]

I get tables with millions of rows. For plotting to a screen-size jpg, obviously just about 1000 points are enough. Instead of feeding plot() the original millions of rows, I'd rather shrink the original dataframe, using some kind of the following interpolation: -- split dataframe into chunks of N rows each, e.g. 1000 rows each -- compute average for each column -- issue one new row

...he tree representation to evalute the fitting. (stress, cophenetic correlation (pearson's correlation)...) "The cophenetic similarity of two objects a and b is defined as the similarity level at wich objects a and b become members of the same cluster during the course of clustering" Legendre, P and Legendre, L Numeri Ecology, 1998. I've made a (tricky) function to compute this cophenetic matrix. But now I need some help to evaluate my function with your data. Because for little matrix (as Legendre's example), I found the same cophenetic correlation as Matlab do (direct calcu...

Dear R-users I applied vegan's varpart function to partition the effects of explanatory matrices. Adj. R square for the unique fraction [a] is 0.25. Does anyone know why the decomposition by hand using rda gives me a different result for [a] (constrained proportion is 0.32)? I used cbind() for the conditional fractions, but it should be similar to condition()? Thanks very much