913 search results for "parallel"

Implementing mclapply() on Windows: a primer on embarrassingly parallel computation on multicore systems with R

July 14, 2014
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An easy way to run R code in parallel on a multicore system is with the mclapply() function. Unfortunately, mclapply() does not work on Windows machines because the mclapply() implementation relies on forking and Windows does not support forking. For me, this is somewhat of a headache because I am used to using mclapply(), and

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Parallel computing in R

July 1, 2014
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Parallel computing in R

Roughly a year ago I published an article about parallel computing in R here, in which I compared computation performance among 4 packages that provide R with parallel features once R is essentially a single-thread task package. Parallel computing is incredibly useful, but not every thing worths distribute across as many cores as possible. Actually,

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Summing a Vector in Parallel with RcppParallel

June 28, 2014
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Summing a Vector in Parallel with RcppParallel

The RcppParallel package includes high level functions for doing parallel programming with Rcpp. For example, the parallelReduce function can be used aggreggate values from a set of inputs in parallel. This article describes using RcppParallel to sum an R vector. Serial Version First a serial version of computing the sum of a vector. For this we use a simple call to the STL std::accumulate function: #include...

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Transforming a Matrix in Parallel using RcppParallel

June 28, 2014
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Transforming a Matrix in Parallel using RcppParallel

The RcppParallel package includes high level functions for doing parallel programming with Rcpp. For example, the parallelFor function can be used to convert the work of a standard serial “for” loop into a parallel one. This article describes using RcppParallel to transform an R matrix in parallel. Serial Version First a serial version of the matrix transformation. We take the square root of each...

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sugar in parallel

June 18, 2014
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sugar in parallel

I've been playing with parallelising Rcpp11 implementation of sugar. For example, we have a NumericVector variable x and we want to compute e.g. sqrt(exp(x)) + 2.0. With sugar, we can do: NumericVector y = sqrt(exp(x)) + 2.0 ; and this does not...

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Rth: a Flexible Parallel Computation Package for R

June 17, 2014
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Rth:  a Flexible Parallel Computation Package for R

I’ve been mentioning here that I’ll be discussing a new package, Rth, developed by me and Drew Schmidt, the latter of pbdR fame.  It’s now ready for use!  In this post, I’ll explain what goals Rth has, and how to use it. Platform Flexibility The key feature of Rth is in the word flexible in

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Rth: a Flexible Parallel Computation Package for R

June 17, 2014
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Rth:  a Flexible Parallel Computation Package for R

I’ve been mentioning here that I’ll be discussing a new package, Rth, developed by me and Drew Schmidt, the latter of pbdR fame.  It’s now ready for use!  In this post, I’ll explain what goals Rth has, and how to use it. Platform Flexibility The key feature of Rth is in the word flexible in

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Hyperthreading FTW? Testing parallelization performance in R.

March 7, 2014
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Hyperthreading FTW? Testing parallelization performance in R.

Alright, let's test some parallelization functionalities in R.The machine:MacBook Air (mid-2013) with 8 GB of RAM and the i7 CPU (Intel i7 Haswell 4650U). This CPU is hyper-threaded, meaning (at least that's my understanding of it) that it has two...

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Mumbai, Feb 2014 – HPC and Parallel R

February 17, 2014
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(This article was first published on Rmetrics blogs, and kindly contributed to R-bloggers) To leave a comment for the author, please follow the link and comment on his blog: Rmetrics blogs. R-bloggers.com offers daily e-mail updates about R news and tutorials on topics such as: visualization (ggplot2, Boxplots, maps, animation), programming (RStudio, Sweave, LaTeX, SQL, Eclipse, git, hadoop, Web...

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Parallelizing #RStats using #make

January 30, 2014
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In the current post, I'll show how to use R as the main SHELL of GNU-Make instead of using a classical linux shell like 'bash'. Why would you do this ? awesomeness Make-based workflow management Make-based execution with --jobs. GNU make knows how to ...

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