Hi again everyone
I have an arbitrarily dimensional array "a" and a list "jj" of length length(dim(a)). The elements of jj are vectors of indexes.
How do I use do.call() to extract a[ jj[[1]], jj[[2]], jj[[3]], ...] ?
Toy example follows:
a <- matrix(1:30,5,6) jj <- list(5:1,6:1)
I want the following
a[ jj[[1]],jj[[2]] ]
How do I do this?
OBAttempts:
do.call("[",list(a,jj))
do.call("[",c(a,jj))
do.call("[",list(a,unlist(jj)))
Of course, the one that works is
do.call("[",list(a,jj[[1]],jj[[2]]))but I don't know how long jj is apriori so this won't do. -- Robin Hankin Uncertainty Analyst Southampton Oceanography Centre SO14 3ZH tel +44(0)23-8059-7743 [EMAIL PROTECTED] (edit in obvious way; spam precaution)
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