getneff.m

Non-parametric density estimation

function Neff = getNeff(dens)
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% getNeff(P)
%  returns an estimate of Neff, the 'effective' number of points in the NPDE
%   (= sum(1/weights^2) )
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% Copyright (C) 2003 Alexander Ihler; distributable under GPL -- see README.txt

  Neff = 1/sum(getWeights(dens).^2);