similar to: modeling language for optimization problems

Hi all, Thanks for the wonderful forum with all the valuable help and comments here. I have been a splus user for the past 7 to 8 years and now crossing the mind of changing over to R. Have been doing a lot of reading and one of the main reasons is being an open source and the wonderful things that comes with that. My question is though, is it possible to export any of the function or librarys

Recently, a package for convex optimization was announced for Python, based upon the LP solver GLPK, the SDP solver in DSDP5, and the LP and QP solvers in MOSEK. I'm aware GLPK is available for R, but wondered if anyone had good packages for convex optimization along these lines for R. TIA.

From: Prof Brian Ripley [mailto:ripley at stats.ox.ac.uk] > On Wed, 28 Nov 2001, Janusz Kawczak wrote: > > > R-users and R-developers: > > > > do you know of any package in R (or for R) that can perform optimizations > > for a linear and non-linear systems? I am aware of the NUOPT module in > > S-Plus that provides an optimizer engine to do just that and more.

Dear all, I am a relative newcomer to the R language, and am sussing out the possibilities of using R to do integer programming (which I am also new to). Is there something along the lines of the NUOPT S- PLUS package that is available, or on the way, for R? Are there other options for integer programming in R? Thanks very much in advance, Robin Naidoo University of Alberta Edmonton, AB,

Hello, I'm trying to get percentiles (PERCENTRANK for excel users) by factor in the following data.frame: myExample <- data.frame(Ret=seq(-2, 2.5, by=0.5),PE=seq(10,19),Sectors=rep(c("Financial","Industrial"),5)) myExample <- na.omit(myExample) Thanks to Patrick I I managed to put together the following lines which does it for the "Ret" column: myecdf

I have a piece of code (from Xie et al. 2009 Autophagy 5:217) that runs in R and requires the glpk package. A year or so ago, I was able to download and install the glpk package directly from insider the R program (for Windows), and everything worked fine. Now I have installed R for Windows on a new computer, and I cannot find the glpk package on the list of available packages on my local

Hi. I am aware of three different R packages for linear programming: glpk, linprog, lpSolve. From what I can tell, if there are N variables and M constraints, all these solvers require the full NxM constraint matrix. Some linear solvers I know of (not in R) have a sparse matrix input format. Are there any linear solvers in R that have a sparse matrix input format? (including the

Hello everybody, I am looking for a function (or package) which can solve a integer optimization problem. I have found the glpk package but I don't known very well how to use it. Someone has another solution ? thx

In my post at https://stat.ethz.ch/pipermail/r-help/2011-October/292019.html I included an undefined term "ej". The problem code should be as follows. It seems like a simple linear programming problem, but for some reason my code is not finding the solution. obj <- c(rep(0,3),1) col1 <-c(1,0,0,1,0,0,1,-2.330078923,0) col2 <-c(0,1,0,0,1,0,1,-2.057855981,0) col3

Can optimisation (simplex etc) be done through R?

Dear listers, a central problem in conservation biology is the selection of sites in reserve network design. many algorithms have been published, and I was wondering any have been implemented in R. I did not seen anything on CRAN or R-help, or on the web in general. Best regards, Eric Eric Pante ---------------------------------------------------------------- College of Charleston, Grice

Hi All, I am looking for references on R as a programming language (apart form the standard R-lang.pdf and the other manuals), reference that would cover _in_depth_ things like loops, code optimisation, debugging tools etc... and is as up-to-date as possible. Can anyone suggest any book or other reference apart from the "green book" and the V&R "S-programming"? Cheers,

Dear list members, I am trying to get information on how to fit a linear regression with constrained parameters. Specifically, I have 8 predictors , their coeffiecients should all be non-negative and add up to 1. I understand it is a quadratic programming problem but I have no experience in the subject. I searched the archives but the results were inconclusive. Could someone provide suggestions

I am currently the only use-R at my company, but they are considering buy a more powerful server and letting multiple people use it. They asked me if R supports client-server setups. I know S+ has a server version that does that. I didn't find anything about that on CRAN, but hopefully someone can correct me. I did see some stuff about R web servers

I would like to call C routines from Fortran under linux as suggested in section 5.6 of the "Writing R extensions" documentation. I'm familiar with Fortran but not with C. I understand the example provided in Fortran: subroutine testit() double precision normrnd, x call rndstart() x = normrnd() call dblepr("X was", 5, x, 1) call rndend() end but I don't understand

Hi, Does anyone know if R has the functionality to calculate a simple moving average. I cant seem to find it in the help menu. thanks, Wayne Dr Wayne R. Jones Statistician / Research Analyst KSS Group plc St James''s Buildings 79 Oxford Street Manchester M1 6SS Tel: +44(0)161 609 4084 Mob: +44(0)7810 523 713 KSS Ltd A division of Knowledge Support Systems Group plc Seventh

Hi, It is my understanding that the eigenvectors of a circulant matrix are given as follows: 1,omega,omega^2,....,omega^{p-1} where the matrix has dimension given by p x p and omega is one of p complex roots of unity. (See Bellman for an excellent discussion on this). The matrix created by the attached row and obtained using the following commands indicates no imaginary parts for the

Assume we have a function like: foo <- function(x, y) how is it possible to define a binary indexing operator, denoted by $, so that x$y functions the same as foo(x, y)

Dear everyone, I don't know much about Integer Programming but am afraid I am facing a problem that can only be solved via Integer Programming. I was wondering if those of you who have experience with it could recommend an R package. I found the following R packages: Rglpk glpk lpSolve lpSolveAPI Are there any others? Are some of them easier to use than others for a beginner? Any advice

On 08/04/2011 11:35, FlyLanguage wrote: > Do your own benchmarking, on the stuff that matters to you. It's the > only fair benchmark you'll ever see. I agree, but this is somewhat extreme point of view. Some general comparisons could also be of interest. For example, performance comparison of some deterministic software like GLPK solver, or compiler itself would be interesting to