[R-sig-hpc] Get identical results for parallel and sequential?

[Dirk Eddelbuettel]

On 11 February 2012 at 15:27, Libo Sun wrote:
| Hi All,
| 
| I have a question about R parallel computing by using snowfall.
| 
| How can I set the seeds on parallel workers to get the same result as
| sequential mode?
| 
| For example:
| 
| > sfSapply(c(1,1),rnorm)
| [1]  1.823082 -2.222052
| > rnorm(2)
| [1] -0.5179967 -1.0807196
| 
| How to get the identical result?

By making sure the RNG streams are initialised identically on all nodes.

Dirk

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