[R] How to set up multiple spawns of R?

[Dirk Eddelbuettel]

On 1 March 2008 at 09:19, Guy Perry wrote:
| Sorry: resending this; didn't have a title on it.
| 
| Trying to set up multiple spawns of R
| -------------------------------------------
| 
| Hi.  I'm new to the list but I have a small problem with R.  I'm trying to
| set up multiple spawns of R active at the same time on an AMD with a dual
| core in Vista so that I can cut down my permutation processing time.  
| 
| I've installed R in multiple places, which I thought was the correct way to
| do it but whether I use installs at "C:\Program Files\R1" and "C\...\R2", or
| even separately on the C: and D: drive, whenever I try to load my package
| (qtl), it gives me the error message:
| 
| Error in library(qtl) : there is no package called 'qtl'
| 
| The thing is, I've installed the packagen in both places (C\...\R1 and
| C\...\R2, or both the C: and D: drives) and it still gives me the message. 
| Does anyone know how to set up a simultaneous R spawn?  Clearly I'm wrong
| about how to get it started.

Afraid so. What made you think you needed to _install R multiple times_ in
order to _run R multiple times_ ?  In short, you don't.

R's core engine is single-threaded, so there is no obvious shortcut. That
said, yopu can of course use parallel coding toolkits like Rmpi to spawn
multiple R session -- which may be beneficial even if you don't have multiple
cores.   These things have been discussed a few times, so some focused Google
queries (or RSiteSearch() queries) may help.

Hth, Dirk

-- 
Three out of two people have difficulties with fractions.