Finding indices with a certain property

I want the indices  i  for which  x[i] < 0 (say):

x <- c(1, -1, 3, 3, -2)
where.negative(x)

[1] 2 5

Try "which(x<0)".

Jonathan Rougier                       Science Laboratories
Department of Mathematical Sciences    South Road
University of Durham                   Durham DH1 3LE

"[B]egin upon the precept ... that the things we see are to be 
 weighed in the scale with what we know"  (Meredith, 1879, The Egoist)

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