[R-sig-hpc] Parallel computation on vectorized function

[Megh Dal]

Thanks Brian for your reply. Would you mind to give me an example how you have achieved that with foreach package? I could then try with the snowfall package in windows.

Thanks,


----- Original Message -----
From: Brian G. Peterson <brian at braverock.com>
To: Megh Dal <megh700004 at yahoo.com>
Cc: "r-sig-hpc at r-project.org" <r-sig-hpc at r-project.org>
Sent: Saturday, August 27, 2011 8:14 PM
Subject: Re: [R-sig-hpc] Parallel computation on vectorized function

On Sat, 2011-08-27 at 07:41 -0700, Megh Dal wrote:
> Dear all, I am looking for some way on how to parallelize some computation on a vectorized function. I have a custom made vectorized function and also have a very length vector (of length some 2 million entries.)
> 
> There are equivalents for all apply family of functions however could not find any way how to apply some parallel computation on a single vectorized function. I have tried with making my vector to list (of same length) and then applying sfLapply() function. However this process is actually taking more time.
> 
> I am using windows vista machine and snowfall package.

take a look at the iterators package, it can chunk up your vector.
I use it with foreach, but there's no reason you couldn't use it to
chunk something up in snowfall.

-- 
Brian G. Peterson
http://braverock.com/brian/
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