matrix indexing

Hi,

you might not consider this more elegant, but how about this

x[-apply(ind, 1, function(i) (i[1]-1)*nrow(x) + i[2])]

Ben
Dear R-users,

I was wondering for the following:

Let 'x' be a matrix and 'ind' and indicator matrix,
i.e.,

x <- array(1:20, dim = c(4, 5))
ind <- array(c(1:3, 3:1), dim = c(3, 2))

I'd like to get (as a vector) the elements of 'x'
which are not indexed by 'ind'. Since negative indices
are not allowed in index matrices I thought of using
something like:

x[ind] <- NA
x[!is.na(x)]

but are there any more elegant solutions.

Thanks in advance,
toka

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matrix indexing

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