26 lines
624 B
R
26 lines
624 B
R
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# a simple parallel random forest
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library(foreach)
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library(randomForest)
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# generate the inputs
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nr <- 1000
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x <- matrix(runif(100000), nr)
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y <- gl(2, nr/2)
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# split the total number of trees by the number of parallel execution workers
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nw <- getDoParWorkers()
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cat(sprintf('Running with %d worker(s)\n', nw))
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it <- idiv(1000, chunks=nw)
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# run the randomForest jobs, and combine the results
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print(system.time({
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rf <- foreach(ntree=it, .combine=combine, .multicombine=TRUE,
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.inorder=FALSE, .packages='randomForest') %dopar% {
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randomForest(x, y, ntree=ntree, importance=TRUE)
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}
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}))
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# print the result
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print(rf)
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