Your code generates an error that has nothing to do with dopar. I have no idea what your function stack is supposed to do; you may be inadvertently calling utils::stack which would produce this kind of error:
> stack(1:25, RAT = FALSE) Error in data.frame(values = unlist(unname(x)), ind, stringsAsFactors = FALSE) : arguments imply differing number of rows: 25, 0 HTH, Peter On Wed, Dec 6, 2017 at 10:03 PM, Kumar Mainali <kpmain...@gmail.com> wrote: > I have used foreach() for parallel computing but in the current problem, it > is not working. Given the volume and type of the data involved in the > analysis, I will try to give below the complete code without reproducible > example. > > In short, each R environment will draw a set of separate files, perform the > analysis and dump in separate folders. > > splist <- c("juoc", "juos", "jusc", "pico", "pifl", "pipo", "pire", "psme") > covset <- c("PEN", "Thorn") > > foreach(i = 1:length(splist)) %:% > foreach(j = 1:length(covset)) %dopar% { > > spname <- splist[i]; spname > myTorP <- covset[j]; myTorP > > DataSpecies = data.frame(prsabs = rep(1, 10), lon = rep(30, 10), lat = > rep(80, 10)) > myResp = as.numeric(DataSpecies[,1]) > myRespXY = DataSpecies[, c("lon", "lat")] > # directory of a bunch of raster files specific to each R environment > rastdir <- paste0(rootdir, "Current/", myTorP); rastdir > rasterc = list.files(rastdir, pattern="\\.tif$", full.names = T) > print(rasterc) > myExplc = stack(rasterc, RAT=FALSE) > } > > I get the following error message that most likely generates while stacking > rasters because there are 25 rasters in the folder of each environment. > Also, in the normal for loop, this reads all fine. > Error in { : > task 1 failed - "arguments imply differing number of rows: 25, 0" > > Thank you. > ᐧ > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.