similar to: R_alloc vs. malloc

# The result I am after is the result after a substitution in an expression, such as substitute(expression(a+b+c), list(a=1)) expression(1 + b + c) # However, the way I want to do it is for a an expression "stored as a variable" as (expr <- expression(a+b+c)) expression(a + b + c) # a) The following does not work (expr2 <- substitute(expr, list(a=1))) expr # b) - whereas this

I have a .txt file obtained by saving a data frame in which the first four columns are factors (but represented as 1,2,3 etc). The first four lines are "Pig" "Evit" "Cu" "Litter" "Start" "Weight" "Feed" "Time" "4601" "1" "1" "1" 26.5 26.5 NA 1 "4601" "1"

Hi, I am trying to implement an algorithm in C which will be called via the .Call() interface. While reading the 'Writing R Extension' manual, I stumbled upon the R_alloc() function for allocating storage for C objects. The manual says it should be used to allocate storage if an C object is needed/created while manipulating R objects within a function called via the .Call() interface.

Dear list I have a function and a vector, say f <- function(a,b){a+b} x <- c(2,3) I want to "evaluate f on x" in the sense of computing f(x[1],x[2]). I would like it to be so that I can write f(x). (I know I can write a wrapper function g <- function(x){f(x[1],x[2])}, but this is not really what I am looking for). Is there a general way doing this (programmatically)?

Dear all, In SAS (GLM and MIXED) estimable functions (linear functions of the parameters) can be specified in the ESTIMATE and CONTRAST statements. Has anyone written a similar "utility" for use in connection with lm? Thanks in advance S?ren H?jsgaard -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read

Thanks. I wonder if there is a general way of extracting var(u) and var(e), which would be needed to simulate u and e. Clearly, one can get the estimated parameters, but is there a clever way of 'setting up' the matrices?? Best S??ren On 6/19/05, S??ren H??jsgaard <Soren.Hojsgaard at agrsci.dk> wrote: > I would like to draw a sample from a linear mixed model y=Xb+Zu+e which has

I want to write a little stand-alone C program that calls R_alloc, but I get a segmentation fault: int main(int argc, char** argv){ double* d = (double *)R_alloc(2, sizeof(double)); // <- segmentation fault! return 0; } gdb reveals that sizeof(double) evaluated to 0: > R_alloc (nelem=2, eltsize=0) at memory.c:1649 so it results in the segfault later. This is how I compile my

Dear All, In a package, I want to use some C code where I am using a structure (as the basic element of a linked list) with flexible array members. Basically, this is a structure where the last component is an incomplete array type (e.g., Harbison & Steel, "C, a reference manual, 5th ed.", p. 159) such as: struct Sequence { struct Sequence *next; int len; unsigned int

I am calling 'vmmin' several times from a C function (which is called via .C). It works very well, except for memory consumption. The cause is that vmmin allocates memory via R_alloc, and this memory is not freed as vmmin exits. Instead all the allocated memory is freed on return of the .C call. In one application, I have 2000 functions of 500 variables each to minimize. In each call to

>From time to time people request symbolic computations beyond what D() and deriv() etc can provide. A brief look at the internet shows that there are many more or less developed computer algebra packages freely available. Therefore, I wondered if it would be an idea to try to 'integrate' one of these packages in R, which I guess can be done in more or less elegant ways... I do not know

Full_Name: Wolfgang Huber Version: R-devel_2005-03-10 OS: alphaev68-dec-osf4.0f Submission from: (NULL) (62.253.128.15) This report concerns allocation of large (>2^31 byte) chunks of memory with R_alloc. I suspect it is a bug/typo but please don't hate me if it's actually a feature: In R, I can happily create large matrices: > a= matrix(0, nrow=191481, ncol=3063) > dim(a) [1]

Dear all; I would like to draw a graph with vertices and edges, and I guess tcl/tk would be appropriate. I don't know tcl/tk but have googled for a 10-page (or so) introduction to 'getting started with tcl/tk in R' but without any luck. - Does anyone know of the existence of such a document or any other web-based material on the subject? - Does anyone have an (informative) piece of

In xyplot, I would like to get the "data into the panel function" in the following sense: Consider xyplot(scc~time|cowidp, data=cow.s,type=c("l"), panel=function(x,y,subscripts,...){ panel.xyplot(x,y,...) vvv<-cow.s[which(!is.na(cow.s[subscripts,"mastreat"])),"time"] panel.abline(v=vvv,col="red",lwd=2) } ) If I want to use a

Dear all, I need to calculate tr(A B), tr(A B A B) and similar quantities **fast** where the matrices A, B are symmetrical. I've searched for built-in functions for that purpose, but without luck. Can anyone help? Thanks in advance Søren [[alternative HTML version deleted]]

I write a package foo which requires a package bar (from CRAN) to work. So in the DESCRIPTION file I write Depends: bar. I would like it to be so that when one installs foo, then it is automatically checked whether bar is installed, and if not then bar is also installed at the same time. I remember having seen packages which do so, but I can not figure out the mechanism 'Depends: bar' in

I would like to draw a sample from a linear mixed model y=Xb+Zu+e which has been fitted with lme(), i.e. a model y ~ N(Xb, C), where C=Z cov(u) Z' + cov(e). I've tried to figure out how to extract C from an lme object, because that would solve my problem when also using the predict() function, but without any luck. Can anyone help on that?

Hi, I would like to create a plot of y1,y2,y3,y4 against x for several subjects such that y1 and y2 are plotted against x in one panel and y3 and y4 against x in another panel. Thus if there are 3 subjects I should end up with 6 panels. Is there a simple way of doing so (i.e. without calling xyplot() several times, and then padding the results together)?? Regards S?ren

Dear List In a package I want to import the mApply function from the Hmisc package, and I would like to import only that function. 1) If I write "Depends: Hmisc" in the DESCRIPTION file I get the whole Hmisc package, so that is not the way to go ahead. 2) According to "Writing R extensions", sec 1.6.1 "Specifying imports and exports" I can (as I read it) simply

Hi! Consider d <- data.frame(x=1:10,y=5+1:10, yf=rnorm(10,5+1:10)) x y yf 1 1 6 5.268621 2 2 7 8.623896 3 3 8 8.114830 4 4 9 10.125955 5 5 10 9.977261 ... I plot y and yf against x with xyplot(y+yf~x,data=d,col=c('red','green'),pch=c("a","b")) BUT - I would like that the plot of y against x is with type='l' and the

Dear all, In S+, there are functions like create.ole.object call.ole.method release.ole.object for communicating with other programs which work as a COM server (on Windows). Is it possible to do something similar in R (I've studied the 'connections' facilities, but they do not seem to work). ========================================== S?ren H?jsgaard, PhD, Senior Scientist