similar to: Single-threaded aspect

On 12 May 2016 at 13:11, Mark van der Loo wrote: | Charles, | | 1. Perhaps this question is better directed at the R-help or | R-pacakge-devel mailinglist. | | 2. It basically means that R itself can only evaluate one R expression at | the time. | | The parallel package circumvents this by starting multiple R-sessions and | dividing workload. | | Compiled code called by R (such as C++ code

Charles, 1. Perhaps this question is better directed at the R-help or R-pacakge-devel mailinglist. 2. It basically means that R itself can only evaluate one R expression at the time. The parallel package circumvents this by starting multiple R-sessions and dividing workload. Compiled code called by R (such as C++ code through RCpp or C-code through base R's interface) can execute

Thank you Simon for the detailed reply. That explains much more of what I was looking for from the R side. Dirk, I'm sorry if I seem hung up on anything here but I am trying to understand the details. My reply about XPtr or XPtr on arma/Eigen was to confirm my understanding was correct, which it appears it was. I was not aware the RVector/RMatrix objects don't connect to R as I am just

Thanks for the replies. Regarding the answer by Dirk, I didn't feel like I still understood the reasoning why mclapply or foreach cannot handle XPtr objects. Instead of cluttering the SO question with comments I was getting the impression that this was a limitation inherited with R objects (which XPtr is supposed to be a proxy for an R object according to Dirk's comment). If this is not

Thank you Dan but it isn't my tests that are failing (all of them pass without problem) but one of the examples from the inst/examples directory. I did try, however, to start R with the environmental variables as you suggest but it had no effect on my tests. Charles On Wed, May 13, 2015 at 1:51 PM, Dan Tenenbaum <dtenenba at fredhutch.org> wrote: > > > ----- Original Message

I have a function in R that takes another function as argument: f <- function(g, ...) { #g is expected to be a function } I want to see if there is a way to implement "f" in C and calling it from R using ".C" interface. I know that I can use function pointers for my C implementation, but I imagine it's going to be nearly impossible to pass a function from R to C. Are

Hi all, I'm not sure if I'm not supposed to do the following (the dyn.unload part, I mean) or this could be a bug (in R or Rcpp): ``` Rcpp::sourceCpp(code=' #include <Rcpp.h> class Object {}; //[[Rcpp::export]] SEXP new_object() { return Rcpp::XPtr<Object>(new Object()); }' ) new_object() dyn.unload(list.files(tempdir(), ".(so|dll)$",

This is strictly a curiosity question. I am aware the R doesn't possess a float data type. I also don't mean to request that such functionality be implemented as I'm sure it would require a large amount of work with potential back compatibility conflicts. But I wanted to know why R has never had a float data type available? Regards, Charles [[alternative HTML version deleted]]

Greetings, I am collaborating with developing the bigmemory package and have run in to a strange problem when we run R CMD CHECK. For some reason that isn't clear to us one of the examples crashes stating: Error: memory could not be allocated for instance of type big.matrix You can see the output on the Travis CI page at https://travis-ci.org/kaneplusplus/bigmemory where the error starts

Dear all, I have an R script that uses Rcpp, and I have been trying to parallelize it using mclapply (I tried with the multicore and the parallel library) Sometimes (not always, interestingly), the CPU use for each core drops, usually so that the total over all cores reaches 100%, i.e., as fast as if using just one single core fully. I tried my code directly from within emacs, and also using a

Hi Dirk, I didn't capture the output but using Focal I got an error with RcppParallel trying to open a file that wasn't found, and plotly::ggplot() would not render a ggplot graph. 20.10 is working well for me otherwise. Frank http://fharrell.com http://biostat.mc.vanderbilt.edu/FrankHarrell Twitter: @f2harrell ---- On Sun, 25 Oct 2020 11:52:43 -0500

Hello, I'm writing an R extension in C++. In the extension, I want to invoke an R function directly and it works when I use Rcpp in the serial code. But what I really want is to invoke the R function in parallel with openmp. When I do so, I got segmentation fault. I remember someone said that R isn't thread-safe. I think it's also understandable because an R function also has

Hi, I have been using R for close to two years now and have grown quite comfortable with the language. I am presently trying to implement an optimization routine in R (Newton Rhapson). I have some R functions that calculate the gradient and hessian (pre requisite matrices) fairly efficiently. Now, I have to call this function iteratively until some convergance criterion is reached. I think the

Dear R Devel, Since Linux moved away from using a file-system interface for audio, I think it is necessary to write special libraries to interface with audio hardware from various languages on Linux. In R, it seems like the appropriate datatype for a `snd_pcm_t` handle pointing to an open ALSA source or sink would be a "connection". Connection types are already defined in R for

Hi there, Although I'm a quite experienced R user and know my ways in C, I stumbled upon a problem I don't know how to solve. Therefore, I hope someone can provide me with the information or pointers I need in order to understand the way in which the communication between R and C occurs. I have the following C code which basicallly reflects what I want: typedef struct { float

I work with problems that have rather large data requirements -- typically a bunch of multigig arrays. Given how generous R is with using memory, the only way for me to work with R has been to use bigmatrices from bigmemory package. One thing that is missing a bit is interoperability of bigmatrices with C++ and possibly java. What i mean by that is API that would allow read and write filebacked

R's dyn.unload() will unconditionally unload the given shared object; it does not check whether there is any object (external pointer or weak reference) with a C finalizer pointing into the space of the shared object being unloaded. So it is expected that R will segfault later when such finalizer is run. Currently there is no other way than to handle this on the side of the shared

I made the mistake of updating to Ubuntu 20.10 from 20.04 before before debian repo supports 20.10.? This broke RcppParallel and plotly.? Any idea with 20.10 will be available for r-cran-* debian packages? Thanks Frank http://fharrell.com http://biostat.mc.vanderbilt.edu/FrankHarrell Twitter: @f2harrell

But you can easily fall back to R from within Julia; see http://juliastats.github.io/RCall.jl/latest/ On Aug 5, 2016 1:27 PM, "Hadley Wickham" <h.wickham at gmail.com> wrote: > No. > > Hadley > > On Fri, Aug 5, 2016 at 11:12 AM, Kenny Bell <kmbell56 at gmail.com> wrote: > > Is it conceivable that Julia could be ported to use R syntax in a way > that

Greetings, I have been exploring the use of the caret package to conduct some plsda modeling. Previously, I have come across methods that result in a R2 and Q2 for the model. Using the 'iris' data set, I wanted to see if I could accomplish this with the caret package. I use the following code: library(caret) data(iris) #needed to convert to numeric in order to do regression #I