Michael That did the trick. Thanks for your help, and I agree with your praise for Prof Ripley.
David On 1/22/2012 1:56 PM, R. Michael Weylandt wrote: > CRAN suggests it's not available for windows since the build can't be > automated: http://cran.r-project.org/bin/windows/contrib/r-release/ReadMe > > but it suggests builds are available from Prof Ripley (to whom be > honor and praise for ever and ever, amen!) here: > http://www.stats.ox.ac.uk/pub/RWin/bin/windows/contrib/2.14/ > > Michael > > On Sun, Jan 22, 2012 at 3:52 PM, David Stevens<david.stev...@usu.edu> wrote: >> I'm following this thread and got curious about Ryacas. After installing >> yacas and Ryacas, I was alerted to the missing XML package for Windows. >> I couldn't find in on a couple of mirrors so I tried >> http://www.omegahat.org/RSXML/ and >> >> install.packages("XML", repos = "http://www.omegahat.org/R";) >> >> but got >> >> Installing package(s) into 'D:/Users/David >> Stevens/Documents/R/win-library/2.14' >> (as 'lib' is unspecified) >> Warning message: >> In getDependencies(pkgs, dependencies, available, lib) : >> package 'XML' is not available (for R version 2.14.1) >> >> for my troubles. The date on the omegahat site is 17 Jan 2012. Am I missing >> something? >> >> David Stevens >> >> >> >> On 1/22/2012 12:39 PM, Gabor Grothendieck wrote: >>> On Sun, Jan 22, 2012 at 1:25 PM, Eliano<eliano.m.marq...@gmail.com> >>> wrote: >>>> People, >>>> >>>> I'm researching some Bayesian statistic topics and in the midle of my study >>>> i found a very simple problem and i'm trying to find a simple package to >>>> solve this type of equations: >>>> >>>> Lets say that i need to compute beta values for the beta distribution and i >>>> now for example: >>>> >>>> E(teta)=a/(a+b) = 0,5 >>>> Var(teta)=ab/((a+b)^2(a+b+1))=0.05 >>>> >>>> So if i want to solve this to non-linear system to find a,b for the beta >>>> distribution wich pack should i use? >>>> >>> The equations giving a and b as a function of m and v are: >>> >>>> library(Ryacas) >>>> a<- Sym("a"); b<- Sym("b") >>>> m<- Sym("m"); v<- Sym("v") >>>> Solve( List(a/(a+b) == m, a*b/((a+b)^2*(a+b+1)) == v), List(a, b) ) >>> expression(list(list(a == m^2 * (1 - m)/v - m, b == a/m - a))) >>> >>> Based on the above we write this R function: >>> >>> beta.parms<- function(m, v) { >>> a<- m^2 * (1-m)/v - m >>> b<- a/m - a >>> c(a = a, b = b) >>> } >>> >>> and run it: >>> >>>> beta.parms(m = 0.5, v = 0.05) >>> a b >>> 2 2 >>> >> -- >> David K Stevens, P.E., Ph.D., Professor >> Civil and Environmental Engineering >> Utah Water Research Laboratory >> 8200 Old Main Hill >> Logan, UT 84322-8200 >> 435 797 3229 - voice >> 435 797 1363 - fax >> david.stev...@usu.edu >> >> >> >> >> [[alternative HTML version deleted]] >> >> ______________________________________________ >> R-help@r-project.org mailing list >> https://stat.ethz.ch/mailman/listinfo/r-help >> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html >> and provide commented, minimal, self-contained, reproducible code. -- David K Stevens, P.E., Ph.D., Professor Civil and Environmental Engineering Utah Water Research Laboratory 8200 Old Main Hill Logan, UT 84322-8200 435 797 3229 - voice 435 797 1363 - fax david.stev...@usu.edu [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
