R help - Feb 2012 - Writting to global variable in using doSNOW on multiple cores?

Hi all,

Is there a problem when accessing/writing to global variable in using
doSNOW package on multiple cores?

In the below program, each of the MyCalculations(ii) writes to the ii-th
column of the matrix "globalVariable"...

Do you think the result will be correct? Will there be hidden catches?

Thanks a lot!

p.s. I have to write out to the global variable because this is a simplied
example, in fact I have lots of outputs that need to be transported from
within the parallel loops... therefore, probably the only way is to write
out to global variables...

library(doSNOW)
MaxSearchSpace=44*5
globalVariable=matrix(0, 10000, MaxSearchSpace)
cl<-makeCluster(7)
registerDoSNOW(cl)
foreach (ii = 2:nMaxSearchSpace, .combine=cbind, .verbose=F) %dopar%
  {
   MyCalculations(ii)
  }

stopCluster(cl)

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