[R] effective way to return only the first argument of "which()"

Jeff Newmiller jdnewmil at dcn.davis.CA.us
Wed Sep 19 17:05:32 CEST 2012


?which.max
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Sent from my phone. Please excuse my brevity.

Mike Spam <ichmagspam at googlemail.com> wrote:

>Hi,
>
>I was looking for a function like "which()" but only returns the first
>argument.
>Compare:
>
>x <- c(1,2,3,4,5,6)
>y <- 4
>which(x>y)
>
>returns:
>5,6
>
>which(x>y)[1]
>returns:
>5
>
>which(x>y)[1] is exactly what i need. I did use this but the dataset
>is too big (~18 mio. Points).
>That's why i need a more effective way to get the first element of a
>vector which is bigger/smaller than a specific number.
>
>I found "match()" but this function only works for equal numbers.
>
>
>
>Thanks,
>Nico
>
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