similar to: S4 slot with NA default

Hi Suppose I have an S4 class "foo" and a validity checking function ".checkfoo()": setClass("foo", representation=representation("numeric")) setValidity("foo" , .checkfoo) is fine; in my application, .checkfoo() verifies that a bunch of necessary conditions are met. But .checkfoo() is very time consuming and I want to give users the option

Hello I am writing a replacement method for an S4 class and want to pass an additional argument to "[<-"() along the lines of "["()'s "drop" argument. Specifically, I have an S4 class, call it "foo", with a slot 'x' that is a vector and a slot 'NC' that is a scalar. I want to be able to pass a Boolean argument to the

Hi suppose I have two arrays x1,x2 of dimensions a1,b1,c1 and a2,b2,c2 respectively. I want x = x1 "+" x2 with dimensions c(max(a1,a2), max(b1,b2),max (c1,c2)) with x[a,b,c] = x1[a1,b1,c1] + x2[a2,b2,c2] if a <=min(a1,a2) , b<=min (b1,b2), c<=min(c1,c2) and the other bits either x1 or x2 or zero according to whether the coordinates are "in range" for

hits=1.0 tests=MANY_EXCLAMATIONS X-USF-Spam-Flag: NO Hi I am writing a package for multivariate polynomials ('multipols') using S3 methods. The package includes a Ops.multipol() function for the arithmetic methods; I would like to define some sort of user-specified Boolean option which, if set, would force results to be simplified as they are produced. Call this option

Hi [this after some considerable thought as to R-help vs R-devel] I want to write a (S3) method for as.function(); toy example follows. Given a matrix "a", I need to evaluate trace(ax) as a function of (matrix) "x". Here's a trace function: tr <- function (a) { i <- seq_len(nrow(a)) return(sum(a[cbind(i, i)])) } How do I accomplish the following:

In the Green Book, section 7.5 discusses new vector classes and uses quaternions as an example of a vector class that needs more than one number per element. I would like to define a new class that has a numeric vector and a logical vector of the same length that specifies whether the measurement was accurate. The following code does not behave as desired: >

Hi How do I test for an object having a particular virtual class? In the following, "onion" is a virtual class, and "octonion" is a non-virtual class contained in onion. The last call to inherits() gives FALSE [R-2.5.0], when inherits.Rd led me to expect TRUE. setClass("onion", representation = "VIRTUAL" )

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 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 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 have a factor and I want to extract just those elements that appear exactly once. How to do this? Toy example follows. > a <- as.factor(c(rep("oak",5) ,rep("ash",1),rep("elm",1),rep ("beech",4))) > a [1] oak oak oak oak oak ash elm beech beech beech beech Levels: ash beech elm oak > table(a) a ash beech elm oak

Hi If string <- "xyz" f <- function(x){1 + sin(cos(x)) + exp(x^2)} How do I manipulate "string" and f() to give the string "1 + sin(cos(xyz)) + exp(xyz^2)" ? -- Robin Hankin Uncertainty Analyst National Oceanography Centre, Southampton European Way, Southampton SO14 3ZH, UK tel 023-8059-7743

Hi. Is there a straightforward way to convert a character string containing comma-delimited numbers to a numeric vector? In my application, I use system(executable.string, intern=TRUE) which returns a string like "[0.E-38, 2.096751179214927596171268230, 3.678944959657480671183123052, 4.976528845643001020345216157, 6.072390165503099343887569007, 7.007958550337542210168866070,

Hi I have a little vector function that takes a vector A of strictly positive integers and outputs a matrix M each of whose columns is the vector, modified in a complicated combinatorical way. Now I want to generalize the function so that A can include zeroes. Given A, I want to strip out the zeroes, pass it to my function, and pad M with rows at positions corresponding to the zeroes

Hi In Sweave, how does one change the size of the plots? I tried using a hook: <<echo=FALSE, print=FALSE, fig=TRUE>>= options(SweaveHooks=list(fig=function() ps.options(width=1))) library(graphics) pairs(iris) @ but this didn't change the size of the figure. How to make the figures a different size? -- Robin Hankin Uncertainty Analyst National Oceanography Centre,

Hi has anyone coded up domain colouring for visualizing complex analytic functions (such as elliptic functions)? [ the idea is to depict a complex function f(z) using a filled.contour() variant in which the hue is given by Arg(f(z)), and the saturation by Mod(f(z)). ] -- Robin Hankin Uncertainty Analyst Southampton Oceanography Centre European Way, Southampton SO14 3ZH, UK tel

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

The following gotcha caught me off-guard just now. I have two matrices, a and b: a <- matrix(1,3,3) b <- matrix(1,1,1) (note that both "a" and "b" are matrices). I want them in a list: > B <- NULL > B[[1]] <- a > B[[2]] <- b > B [[1]] [,1] [,2] [,3] [1,] 1 1 1 [2,] 1 1 1 [3,] 1 1 1 [[2]] [,1] [1,] 1

Hi How do I generate all ways of ordering sets of indistinguishable items? suppose I have two A's, two B's and a C. Then I want AABBC AABCB AACBC ABABC . . .snip... BBAAC . . .snip... CBBAA [there are 5!/(2!*2!) = 30 arrangements. Note AABBC != BBAAC] How do I do this? -- Robin Hankin Uncertainty Analyst National Oceanography Centre, Southampton European Way, Southampton SO14

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