On Fri, 25 Jun 2004, Anne Piotet wrote: > I'd like to compute the values > x(i)-x(n-i-1) for i=1 n/2 or similar (as way of testing distribution symmetry > hypothesis). It is very easy to do that with a loop but can that be avoided?
Is that really what you want (not x[n-i+1])? x - rev(x) gives you the latter for all i. Or try ind <- seq(1, floor(n/2)) (you don't need the floor, but it is clearer) x[ind] - x[n - ind + 1] (or -1 if you prefer). -- Brian D. Ripley, [EMAIL PROTECTED] Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272866 (PA) Oxford OX1 3TG, UK Fax: +44 1865 272595 ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
