[Rd] help(clusterApply) (parallel package)

Viechtbauer Wolfgang (SP)
Wed, 25 Jan 2017 20:22:09 -0000

Hello,

In help(clusterApply) of the 'parallel' package, it says:

"clusterApply calls fun on the first node with arguments seq[[1]] and ...,
on the second node with seq[[2]] and ..., and so on, recycling nodes as
needed."

But the argument that is iterated over in clusterApply() is called 'x'
not 'seq', so shouldn't it read x[[1]], x[[2]], and so on?

Also, 'x' doesn't have to be a vector ("x - a vector for
clusterApply and clusterApplyLB, a matrix for parRapply and parCapply."),
it just needs to be an object for which x[[1]], x[[2]], ... works (e.g., a data
frame works just fine).

"clusterApplyLB is a load balancing version of clusterApply. If the length
p of seq is not greater than the number of nodes n, then a job is sent to p
nodes." Again, shouldn't that say "If the length p of x"?

And finally, "For clusterApply and clusterApplyLB, a list the same length
as seq." Again, 'x' instead of 'seq'?

Best,
Wolfgang

--
Wolfgang Viechtbauer, Ph.D., Statistician | Department of Psychiatry and
Neuropsychology | Maastricht University | P.O. Box 616 (VIJV1) | 6200 MD
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