similar to: Can't reliably use RefClass methods in Snowfall

Dear all, I am trying to execute the simple example in snowfall http://cran.r-project.org/web/packages/snowfall/vignettes/snowfall.pdf ... require(snow) require(snowfall) sfInit( parallel=TRUE, cpus=2 ) sfLapply( 1:10, exp ) sfStop() I have installed the snow and snowfall packages in R on a machine with windows xp, however, after running the "sfInit( parallel=TRUE, cpus=2 )" line I

  Hi,   The code below does exactly what I want in sequential mode. But, it is slow and I want to run it in parallel mode. I examined some windows version packages (parallel, snow, snowfall,..) but could not solve my specific problem. As far as I understood, either I have to write a new function like sfRollapplyr or I have to change my code in a way that it utilizes lapply, or sapply instead of

Dear All, I have a question of how to export S4 class specification to clusters/workers in parallel computing. The package I used is snowfall. The problem is reproducible as follows. Any hint is greatly appreciated. Edwin Sun === begin =========== library(snowfall) sfInit(parallel = TRUE, cpus = 2) setClass("catt", representation(aa = "numeric")) setClass("dogg",

Sorry for wasting your time with an incorrect diagnosis in my previous mail! I'm running my script using mpirun -mp 4 and using snowfall+Rmpi on Linux 64bits. I receive the following error, that terminates the run. Any idea? I'm able to reproduce the problem with a minimal script (below). If n < 16371 it completes 9 iterations without problems. Already at 16371 it dies at iteration 7

I'm running my script using mpirun -mp 4 and using snowfall+Rmpi on Linux 64bits. I receive the following error, but apparently without consequences on the results. Any idea? I'm able to reproduce it with a minimal script (below). Seems the critical issue is the for loop. Without it no error. Thanks for your help! TERM: Undefined variable. TERM: Undefined variable. TERM: Undefined

R-helpers: What would be the absolute fastest way to make a large "empty" file (e.g. filled with all zeroes) on disk, given a byte size and a given number number of empty values. I know I can use writeBin, but the "object" in this case may be far too large to store in main memory. I'm asking because I'm going to use this file in conjunction with mmap to do parallel

Hello, Just wondering why I am unable to run this in parallel. A dput of my dataset is attached at the end. Please use to create my data object. I want to run this function in parallel (not sure if this is an efficient implementation): #Function to calculate the time to maturity for the option require(fCalendar,quietly=TRUE) #Trying to calculate the trading days

Dear all, I just wrote a script to have each of my three mcmc chins running on a different computer core to improve computation speed. To do it I use the function sfLapply from the package snowfall. Before using parallell computation, I did my diagnostic analyses just after the model updating, but now I have to save the coda before. Using the CODA package, it is possible to load the outputs in a

Hello dear R community. I just started playing with the snowfall package (a wrapper for the snow package), and found it very convenient. (See also this great website: http://www.imbi.uni-freiburg.de/parallel/ ) I was wondering if it is possible to connect snowfall with the foreach package (since it has some connection to snow). My final goal is to do some simple parallel simulations on my two

Dear users, I want to set up R to use one R-script directory and one R-library (directory for packages) for many end-users. I try to do this by using one network-share. This works fine as long as we don't use the snowfall package with parallel=TRUE (sfInit(parallel=TRUE, cpus=4, type="SOCK")). When running R with default settings (local library and local script directory)

Dear expeRts, I'm currently trying to get data from a PostgreSQL database _in parallel_. I tried two methods: * passing the DBI Connection object to the cluster nodes * connecting the the DB on each node (1) The execution of the first method looks like this: > result = sfClusterApplyLB(input, fun, dbiCon) and produces an "expired PostgreSQLConnection" error. (Of course the

Hello, I'm trying to run a code that uses the snowfall package. Here is the structure of my code. sfInit(parallel=T, cpus = 5, slaveOutfile="ErrorMessage.txt") sfExportAll() sfLibrary(rgdal) sfLibrary(raster) sfLibrary(sp) sfLibrary(rgeos) sfLibrary(snowfall) system.time( sfClusterApplyLB(1:10, function(k) { sfCat(paste("Iteration ", k),

Guys, Is anyone using snowfall? It seems that the last version is broken. sfinit contains test code: data("config", package = "snowfall") configM <- as.matrix(t(config)) config <- as.list(configM) names(config) <- dimnames(configM)[[2]] .sfOption$SERVER <<- as.character(config[["SERVER"]]) .sfOption$PORT <<-

Dear Ola, I cannot say anything about Windows 7, as we do not have any Win7 machines here in our institute and I even do not know someone who have Win7 on a private machine. I will try to find a machine with this OS and test it. Anybody having experiences with Win7 yet? Greetings Jo > -------- Original Message -------- > Subject: [R] snowfall on Win7 > Date: Tue, 15 Dec 2009 11:25:37

I'm using refClass for a complex multi-directional tree structure with possibly 100,000s of nodes. The refClass design is very impressive and I'd love to use it, but I've found that the size of refClass instances are very large and creation time is slow. For example, below is a RefClass and normal S4 class. The RefClass requires about 4KB per instance vs 500B for the S4 class --

Hi, does anyone know if it is possible to construct sets of S4 objects? It seems the constructor set does not like it: Error in as.vector(x, "character") : cannot coerce type 'environment' to vector of type 'character' Regards Johnny PS: by the way, does anyone know where I can find some examples using the cset class from the "sets" package, beside the

Hi, does anyone know if it is possible to construct sets of S4 objects? It seems the constructor set does not like it: Error in as.vector(x, "character") : cannot coerce type 'environment' to vector of type 'character' Regards Johnny [[alternative HTML version deleted]]

I've been trying to split a space delimited string with double-quotes in R for some time but without success. An example of a string is as follows: /rainfall snowfall "Channel storage" "Rivulet storage"/ It's important for us because these are column headings that must match the subsequent data. Here is some code I've been trying: str <- 'rainfall

Dear R-listers, I have been using Snowfall (version 1.84) for parallel computing on a quad-PC running Windows 7 for a month or so without much problem. I started having problems runnnig R with Snowfall over our network when a new Novell client was installed for Windows 7. I experinenced network mapping problem with this new client. Our network colleague provided a fix which worked but a little

Hello, I'm new to R and I'm building a system that uses a cluster of computers to parallelize computations. To handle cluster setup I'm using the R package Snowfall, but knowledge of Snowfall may not be necessary to answer my question. I'm using a socket-based approach to cluster setup, so all I need to do is give Snowfall a vector of hostnames and it handles the rest. The problem