similar to: using optimize() correctly ...

Hello, which.max() only returns one index value, the one for the maximum value. If I want the two index values for the two largest values, is this a decent solution, or is there a nicer/better R'ish way? max2 <-function(v) { m=which.max(v) v[m] = -v[m] m2=which.max(v) result=c(m, m2) result } Seems to work ok. Thanks, Esmail

Hello, I have the following task I'd like to accomplish: A file contains 5 columns of data (several hundred rows), let's call them a, b, c, d and e (ie these are their column headers) I also have a set of definitions, e.g., f = a + b g = a * 3 h = c + d etc. I would like to write out a new .rda file that contains columns a b c d e f g h etc. I.e. , the original data plus new columns

Hello, Still a newbie with R, though I have learned a lot from reading this list. I'm hoping someone can help with this question: I have two vectors, one for variables, and one for bits. I want to build a string (really a formula) based on the values in my vector of 1s and 0s in bits. If I have a one, I want to include the corresponding entry in the vars vector, otherwise ignore it. Of

Hi, I have matrix of bits and a target vector. Is there an efficient way to search the rows of the matrix for the target? I am interested in the first row index where target is found. Example: > source("lookup.R") [,1] [,2] [,3] [,4] [,5] [1,] 1 0 1 1 0 [2,] 1 1 0 1 0 [3,] 0 0 1 0 0 [4,] 1 0 0 1 1 [5,]

Hola a tod en s, estoy intentando averiguar el número de modas en una distribución. Para ello utilizo diptest. Mi duda es que no acabo de entender cuando la información suministrada por los test suponen la existencia o no de unimodalidad/multimodalidad. Una parte de la salidad de diptest es la que pego a continuación (el resto esta en el fichero adjunto con las distribuciones kernels y las

Once again I need to tap into the collective knowledge here. Let's say I have the following columns and data below Y X1 X2 X3 X4 I would like to generate additional new columns and column names (ie the data would be squared - and I'd like the column names to reflect this) like: Y X1 X2 X3 X4 X1^2 X2^2 X3^2 X4^2 I believe I can compute the values correctly with the code below, but I

Hello all, I have a matrix of bit values. I compute certain values based on the bits in each row. There may be *duplicate* entries in the matrix, ie several rows may be identical. These rows change over time, and identical entries may not be next to each other. Computing these values is time consuming, so I would like a way to store a value once it's computed. That way I would be able to

Dear All, A method for the estimation is univariate unimodal densities (with unknown mode) is described in "Statistical Inference under Order Restrictions" by Barlow et al.. Would anyone know whether there is an R-implementation (preferably with reference) for the estimation of univariate discrete unimodal densities (with unknown mode)? Thanks in advance for your help. Kind

(sorry if this is a duplicate-problems with posting at my end) ---- Hello all, I need some help with a nice R-idiomatic and efficient solution to a small problem. Essentially, I am trying to eliminate randomly half of the entries in a vector that contains index values into some other vectors. More details: I am working with two strings/vectors of 0s and 1s. These will contain about 200

Hello all, I am trying to implement a simple Genetic Algorithm using some of the functions of R (such as lm). I am a total newbie with regard to R, but not programming or GAs. I thought I would have to do this in R but now it seems there are ways to call R functions from Java after all. (C++ would work for me too, having a compiled language should speed up the program.) Are there recommended

Dear All, Does anybody know if there is a functionality in R to break histograms that show a clear bi-modal (or multi-modal) distribution into a series of unimodal histograms that added up result in the original histogram? I was thinking of using QQ-plots (for which tools are available in R), and then observing the number of times the observed quantiles cross the 1:1 line, but this only gives an

Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Virus-Scanned: by amavisd-new X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on hypatia.math.ethz.ch X-Spam-Level: **** X-Spam-Status: No, hits=4.2 required=5.0 tests=MSGID_FROM_MTA_HEADER,RCVD_IN_BL_SPAMCOP_NET autolearn=no version=2.63 Dear r-help list, my question is about ordination technics:

Has a test for bimodality been implemented in R? Thanks, John NIWA is the trading name of the National Institute of Water & Atmospheric Research Ltd.

Colleagues, I have encountered behavior of random number generation that eludes me. I generate a random integer in a particular range using the following code: sample(1000:9999, size=1) This code exists within a script that starts with the command: remove(list=ls()) Each time that I run the script, it yields the same random number: 6420. I thought that the problem might result from

Dear List, I have a set of distributions recorded at an equal interval of time and I would like to plot them as series of horizontal histograms (with the x-axis representing time, and y-axis representing the bins) since the distribution shifts from unimodal to multimodal in several occasions. What I would like to see is something close to a violinplot, but I do not want a kernel density

Hello all, Using Ubuntu 9.04 and R 2.8.1. For a project I need to use the Zelig package, which in turn wants to use the lme4 package. When trying to use Zelig and it tries to its required packages I get the following error message. Error in dyn.load(file, DLLpath = DLLpath, ...) : function 'cholmod_start' not provided by package 'Matrix' Error in loadModelDeps(model) :

Hi all, I have the data from the posterior distribution for some parameter. I want to find the 95% credible interval. I think "t.test(data)" is only for the confidence interval. I did not fine function for the Bayesian credible interval. Could some one suggest me? Thanks [[alternative HTML version deleted]]

Dear all i could not estimate the optima value or range value in unimodal plot in glm please help me out thanking you regard madan _________________________________________________________________ Hotmail® has a new way to see what's up with your friends. orial_WhatsNew1_052009 [[alternative HTML version deleted]]

I'm not sure where to begin with this, but I was wondering if someone could refer me to an R package that would test to see if a distribution fits a bimodal distribution better than a unimodal distribution. Thanks, Andrew [[alternative HTML version deleted]]

Dear all, I new to r and I would like your help. I want to explore the patterns (unimodal, monotonically increased/decreased) of species richness~altitude using GAM in R. Although I run the gam function in mgcv package I do not know how to manually define knots and degrees of freedom. Any help would be greatly appreciated. Spyros -- View this message in context: