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Update unit tests
author | Daniele Nicolodi <nicolodi@science.unitn.it> |
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date | Wed, 07 Dec 2011 17:24:37 +0100 |
parents | f0afece42f48 |
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % % Compute inverse of the Chi square cumulative distribution function % % CALL % % x = Chi2inv(p,v); % % % INPUT % % - p, probability or significance level % - v, degrees of freedom of the distribution % % Example: If you want the 95% confidence interval for a chi2 variable you % should call % % x = utils.math.Chi2inv([0.05/2 1-0.05/2],v) % % References: % [1] M. Abramowitz and I. A. Stegun, "Handbook of Mathematical % Functions", Government Printing Office, 1964, 26.4. % % % L Ferraioli 14-02-2011 % % $Id: Chi2inv.m,v 1.2 2011/05/30 17:18:09 luigi Exp $ % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% function x = Chi2inv(p,v) a = v/2; b = 2; % Call the gamma inverse function. % x = gaminv(p,v/2,2); % uses statistic toolbox q = gammaincinv(p,a,'lower'); x = q.*b; end