[R] vectorize an expression

[Prof Brian Ripley]

On Wed, 2 Apr 2003 Simon.Gatehouse at csiro.au wrote:

> Dear listers,
> I'm having a bad R day.  I just can't think of the vectorized equivalent of:
> 
> for (ii in 1:n)   aa[ii]  =  bb[ii,cc[ii]]

aa <- bb[cbind(1:n, cc[1:n])]

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
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