similar to: Behaviour of very large numbers

Dear R-Gurus, I have ended up with a calculation problem where I need to use brobs. I have to work my way through a vector with a for loop to act on each element in a calculation (refering to the previous value in the new vector of results -- so as far as I know I can't use "apply") -- this produces a list of brobs. My problem is, how do I act on, plot this list, or do vector

Dear R, I have two questions: 1, Why both R and Matlab give 0*Inf==NaN? To my knowledge, it should be zero mathematically. Am I right? 2, I need to calculate e.g. exp(a)/(exp(b)+c), where both a and b are very large numbers (>>1000, e.g a=1000, b=1007, and c=5). R gives me NaN when I use the following command: > exp(1000)/(exp(1007)+5) [1] NaN I am pretty sure this should be close to

Hi If x <- 1:10 then x[5] <- 1i will promote x to be a complex vector. Suppose I have an S4 class "brob", and have functions is.brob(), as.brob(), as.numeric() and so forth (minimal self-contained code below). If x is numeric (1:10, say) and y is a brob, what is the best way to make x[5] <- y promote x to a brob in the same way as the complex example? Or is

Hello everybody R version 2.4.0 alpha (2006-09-15 r39323), MacOSX 10.4.7 Next S4 problem. I have "brob" objects that are large real numbers, and now I want "glub" numbers that are to be a pair of glubs that represent complex numbers. I want to define binary operator "+" so that if either the left or right argument are glubs, it uses .ArithGlub. If either

Hi I am having difficulty with setMethod(). I have a "brob" class of objects whose representation has two slots: "x" and "positive". Slot "x" (double) holds the log of a number and slot "positive" (logical) its sign. The idea is that large numbers can be handled. I'm trying to implement a log() method using an analogue of the

Dear all, I am not sure what I am doing wrong, but I have some unexplained behaviour when saving a lattice graph including text to a pdf file. The text seems to move around. It must have something to do with the way coordinates are set in devices other than jpg. Any suggestions would be helpful Willem Here is some example code setwd("c:/willem/research/misc") today <-

Hi everyone and thanks for being patient. I've used "!.foo"() et seq pro tem. Next problem: how to define "Summary" methods for brobs. ?max says 'max' and 'min' are generic functions: methods can be defined for them individually or via the 'Summary' group generic. For this to work properly, the arguments '...' should be

I am getting the following error message while using the as.brob function in some computations: Error in out.x[ss] <- pmax(x1[ss], x2[ss]) + log1p(+exp(-abs(x1[ss] - : NAs are not allowed in subscripted assignments Is there any obvious mistake I am making here that can resolve the above error message? Thanks for your help. Chow -- View this message in context:

Hi In V&R the "polynomial" class is explicitly specified to have no logical operators: setMethod("Logic", signature(e1="polynomial"), function(e1,e2){stop ("...")}) I too have a class of objects for which I want to specify that Logic operators do not work, but executing setClass("brob", representation = representation

Hi. I am having difficulty following section 1.6.6 of the R-extensions manual. I am trying to update the Brobdingnag package to include a NAMESPACE file (the untb package requires the Brobdingnag package). Without the NAMESPACE file, the package passes R CMD check cleanly. However, if I include a NAMESPACE file, even an empty one, R CMD check gives the following error in 00install.out:

Hi all, I am trying to do an inversion of electromagnetic data with non-negative least squares method (Tikhonov regularisation) and have got it programmed in S-Plus. However I am trying to move all my scripts from S-Plus to R. Is there an equivalent to nnls.fit in R? I think this can be done with pcls? Right? S-Plus script: A, L and data are matrices, lambda is a vector of possible lambda

Hi, I've been using the Matlab robustfit function for linear regressions where I suspect some data points are outliers. Is there an equivalent function in R? Take care, Darren PS, This is the Matlab help on robustfit: >> help robustfit ROBUSTFIT Robust linear regression B = ROBUSTFIT(X,Y) returns the vector B of regression coefficients, obtained by performing robust

Hi R version 2.4.0 alpha (2006-09-06 r39158) MacOSX 10.4.7 There was a thread some time ago as to whether the structure created by package.skeleton() would pass R CMD check. I have an example where package.skeleton() gives an R file that gives an error when sourced. If I type setClass("brob", representation = representation

Hello List. please find uploaded to CRAN a new package, Brobdingnag. This package does two things: (1) allows computation of very large numbers using a logarithmic representation. (2) provides a "Hello, World" example of S4 methods in use: there are two classes of object (brob and glub) and one virtual class (swift). The package includes a vignette that is a

I think Robin knows about FAQ 7.31/floating point (author of 'Brobdingnag', among other numerical packages). I agree that this is surprising (to me). To reframe this question: is there way to get an *exact* ASCII representation of a numeric value (i.e., guaranteeing the restored value is identical() to the original) ? .deparseOpts has ?"digits17"?: Real and finite complex

HI R Gurus, > This is my first foray into using c-code with R, so ... > I had a look at the archives and did not find anything on this, so > hopefully I am not doubling up. > I have previously used the following approach where I needed some very small numbers/large (using Brobdingnag): surfacewithdiff <- function(t, y, p) { const=p["const"] kay

Hi R used with C-code experts, I had a look at the archives and did not find anything on this, so hopefully I am not doubling up. I have previously used the following approach where I needed some very small/large numbers (using Brobdingnag): surfacewithdiff <- function(t, y, p) { const=p["const"] kay =p["kay"] psii=p["psii"]

Dear R-help list, I am trying to construct a lattice histogram using 3 factors. My dataframe looks like this: (simulating a waterbalance over groundwater with different salinities) s days model EC EC_max 0.4 1 "A" 10 9 0.42 2 "A" 10 9 0.44 3 "A" 10 9 : : : :

Thanks guys, I guess I should have referred to FAQ 7.31 (which I am indeed very familiar with) to avoid misunderstanding. I have always used dput() to clarify 7.31-type issues. The description in ?dput implies [to me at any rate] that there will be no floating-point roundoff in its output. I hadn't realised that 'deparsing' as discussed in dput.Rd includes precision roundoff issues.

Since this has come up already: It is a good idea to re-install all packages for a minor-version increment of R, e.g. 2.5.1 -> 2.6.0 (it is major.minor.patchlevel). This is most easily done by > update.packages(checkBuilt=TRUE, ask=FALSE) However, if you don't want to do that yet, be aware that - Certain S4-using packages must be reinstalled, and using old versions can make R