www.gusucode.com > mbcmodels 工具箱 matlab 源码程序 > mbcmodels/@xreglinear/det_xtx.m

    function d=det_xtx(m)
%DET_XTX   Determinant of X'X
%
%   d=DET_XTX(m) calculates |X'X| for the model m

%  Copyright 2000-2007 The MathWorks, Inc. and Ford Global Technologies, Inc.


if ~isfield(m.Store,'Q')
   error(message('mbc:xreglinear:InvalidState2'));
end

r=abs(diag(m.Store.R));

d=exp(2*sum(log(r)));