dynare/nonlinear-filters/probability2.m

37 lines
1.1 KiB
Matlab

function [density] = probability2(mu,S,X)
%
% Multivariate gaussian density
%
% INPUTS
% n [integer] scalar, number of variables.
%
% OUTPUTS
% nodes [double] nodes of the cubature
% weigths [double] associated weigths
%
% REFERENCES
%
%
% NOTES
%
% Copyright © 2009-2017 Dynare Team
%
% This file is part of Dynare.
%
% Dynare is free software: you can redistribute it and/or modify
% it under the terms of the GNU General Public License as published by
% the Free Software Foundation, either version 3 of the License, or
% (at your option) any later version.
%
% Dynare is distributed in the hope that it will be useful,
% but WITHOUT ANY WARRANTY; without even the implied warranty of
% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
% GNU General Public License for more details.
%
% You should have received a copy of the GNU General Public License
% along with Dynare. If not, see <https://www.gnu.org/licenses/>.
dim = size(X,1) ;
normfact = bsxfun(@power,(2*pi),(dim/2)) ;
foo = S\(bsxfun(@minus,X,mu)) ;
density = exp(-0.5*sum(foo.*foo)')./abs((normfact*prod(diag(S)))) + 1e-99 ;