[R] subsetting from a vector or matrix

[andrew]

both the following will probably do the trick.

?subset
?"["

Basically on the second one, you want to come down to something that
looks like

x[L]

where x is a matrix/vector, and L is a logical vector that has the
same dimension as x, but is TRUE on the values of x that you want to
select.

for instance

x <- rnorm(100000)
L <- x > 3
x[L] will return all values of x that are greater than 3.

or you can just do

x[x>3]



On Sep 25, 9:45 am, "Jim Bouldin" <jrboul... at ucdavis.edu> wrote:
> I realize this should be simple but I'm having trouble subsetting vectors
> and matrices, for example extracting all values meeting a certain
> criterion, from a vector. Cannot seem to figure out the correct syntax and
> help page not very helpful.  Or should I be using some other function than
> subset.  Thanks for any help.
>
> Jim Bouldin
>
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