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revolution foreach oddity

2 messages · pdb, David Smith

pdb
# 
I know this is not a revolution support forum, but as anyone noticed the
following?

I have a foreach loop to generate random samples. If I run the exact code
below in normal r (2.14.1) it works as expected, but if I run it from
revolution 4.2.0 each loop returns the same numbers.

The only way I can get revolution to give different numbers is using 1
instead of 8 in
registerDoSNOW(makeCluster(8, type = "SOCK"))

but that seems to defeat the point. 




library(foreach)
library(doSNOW)
registerDoSNOW(makeCluster(8, type = "SOCK"))
getDoParWorkers()
getDoParName()
getDoParVersion()


mySamples <- foreach (jj = 1:4, .combine=cbind) %dopar% {
		return(sample(1:10,10,replace=TRUE))	
		}

mySamples 

##########
r 2.14.1
##########
[1] 8
[1] "doSNOW"
[1] "1.0.6"
+ return(sample(1:10,10,replace=TRUE))
+ }
result.1 result.2 result.3 result.4
 [1,]        5        3        1        4
 [2,]        1       10       10        3
 [3,]        7        9        4        9
 [4,]        2        5        9        3
 [5,]        2        7       10        1
 [6,]        7        8       10       10
 [7,]        6        9       10        4
 [8,]        8        6        6        2
 [9,]       10        7        9        4
[10,]        2        4        1        9
####################
# revolution r
####################
Loading required package: iterators
Loading required package: codetools
foreach: simple, scalable parallel programming from REvolution Computing
Use REvolution R for scalability, fault tolerance and more.
http://www.revolution-computing.com
Loading required package: snow
[1] 8
[1] "doSNOW"
[1] "1.0.3"
+ 		return(sample(1:10,10,replace=TRUE))	
+ 		}
result.1 result.2 result.3 result.4
 [1,]        4        4        4        4
 [2,]       10       10       10       10
 [3,]        4        4        4        4
 [4,]       10       10       10       10
 [5,]        5        5        5        5
 [6,]        5        5        5        5
 [7,]        9        9        9        9
 [8,]        2        2        2        2
 [9,]        6        6        6        6
[10,]        9        9        9        9
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