I have a function doSomething() which runs in a foreach loop and as a result saves some calculations as .csv files. Hence I have no need for a return value of foreach, in fact I don't want a return...

I am running a parallelized calculation using foreach to work on a lot of time series simultaneously. Among those calculations (within a function called compute_slope() I do something like this lBd...

Another potential title for this post could be "When parallel processing in R, does the ratio between the number of cores, loop chunk size, and object size matter?" I have a corpus I am r...

I'm trying to train several random forests (for regression) to have them compete and see which feature selection and which parameters give the best model. However the trainings seem to take an ins...

I have an input csv file with 4500 rows. Each row has a unique ID and for each row, I have to read some data, do some calculation, and write the output in a csv file so that I have 4500 csv files w...

I'm trying to ensemble several neural networks using keras for R. In order to do so, I would like to parallelize the training of the different networks by using a "foreach" loop. models <- lis...

I have the following simple example Rmarkdown document (test.Rmd): --- title: "Test Knit Caret Paralell VerboseIter" output: html_document --- ```{r setup, include=FALSE} knitr::opts_chunk$set(ec...

I have a Threadripper 1950X based workstation with 16 cores and 32 threads and plenty of memory. Running 64-bit R 3.6.0 (patched) on Windows 10, I frequently run parallel code in R using the doPara...

I am creating a DocumentTermMatrix using create_matrix() from RTextTools and create container and model based on that. It is for extremely large datasets. I do this for each category (factor leve...

I read you had to use stopCluster() after running parallel function: foreach() in R. However, I can get away with registerDoParallel() and then running foreach() as many times as I want without eve...

I have a dataset with few numeric columns and over 100 millions of rows as a data.table object. I would like to do group operations on some of the columns based on other columns. For example, count...

I have a problem with Render_site using the dopar of foreach The code works perfectly using simple for. Whereas I have a problem when using dopar since the ouput is duplicated after using dopar in ...

How can I export the global environment for the beginning of each parallel simulation in foreach? The following code is part of a function that is called to run the simulations. num.cores <- d...

I'm trying to decrease run time of my code by using doParallel package in R. I'm calling a function awareRateSIR that some extra packages are used in the body of this function. I get some error li...

What is the difference between cluster and cores in registerDoParallel when using doParallel package? Is my understanding correct that on single machine these are interchangeable and I will get sa...

I have a function that contains a loop myfun = function(z1.d, r, rs){ x = z1.d[,r] or.d = order(as.vector(x), decreasing=TRUE)[rs] zz1.d = as.vector(x) r.l = zz1.d[or.d] y=vector() for (i ...

How to avoid "could not find function "%dopar%"" in a function of a package when only imports (not depends) foreach in DESCRIPTION of a package? is there a way like foreach::%dopar% as I use foreac...

I'm new to using foreach() %dopar% for paralleling, and I have some problems about how it handles errors or warnings. when I use try() with my customized error message within foreach() %dopar%, t...

I wrote a simple matrix multiplication to test out multithreading/parallelization capabilities of my network and I noticed that the computation was much slower than expected. The Test is simple : ...

This is a very simple example. df = c("already ","miss you","haters","she's cool") df = data.frame(df) library(doParallel) cl = makeCluster(4) registerDoParallel(cl) foreach(i = df[1:4,1], .comb...

I am currently working with some large datasets, so parallelizing the workflows is the only way to go. I need to load some packages to each thread once at the beginning (i.e: for(this.thread in t...

How would i go about running RSelenium in parallel. The following is an example using rvest in parallel library(RSelenium) library(rvest) library(magrittr) library(foreach) library(doParallel) U...

I'm running the following code (extracted from doParallel's Vignettes) on a PC (OS Linux) with 4 and 8 physical and logical cores, respectively. Running the code with iter=1e+6 or less, every thi...

I have a problem with foreach that I just can't figure out. The following code fails on two Windows computers I've tried, but succeeds on three Linux computers, all running the same versions of R a...

I have the following R-code: library(doParallel) cl <- makeCluster(detectCores()-4, outfile = "") registerDoParallel(cl) calc <- function(i){ ... #returns a dataframe } system.time( res&lt...