beldst.m

DS证据推理的置信函数（bel）的计算函数

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%   The coryright belongs to Yang Yang,Automation Institute,NPU,710072
%   Xi'an, China      
%   EDITION NUMBER: 1.0
%   Contract me : E-mail [e-mail] ,
%                 Mobile : [phone],
%                 Home :   029-82375332
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

function Bel=BelDST(mass)
%   calculate the Belief Function from bba m(.) in DST, the format is:
%   Bel=BelDST(mass)
%   mass: mass function,it is a vector for a  column.It have 4 elements
%        for two  class and 8 elements for three class ,the size is n*1.
%   Bel: output the Belief Function from gbba m(.),it have 4 elements
%        for two  class and 8 elements for three class ,the size is n*1.
% Interpretion:
%   The function can only calculate two or three classes for the Frame
%   within DSmT.If the Frame have 4 elements,  they are denoted in
%   Theta={A,B},and if it  have 8 elements,the Theta={A,B,C}. Then the
%   2^Theta={0,A,B,A|B} for  two dimensions ,2^Theta={0,A,B,A|B,C,A|C,B|C,A|B|C}
%   for three dimesions.  Then the Belief Function   from bba m(.) in DST
%   can be calculate in matrix .    

%   Do not hesitate to contract  me ,if you have any question.

[row,col]=size(mass);
%Judge the classes of the Frame
if row==4
    class=2;
    elseif row==8
            class=3;
    else disp(['The class number of the Frame is not two or three,the function can not be calculated']);
        return;    
end

if class==2
    Bel=[1,0,0,0;
         0,1,0,0;
         0,0,1,0;
         0,1,1,1;]*mass;
end
if class==3
    Bel=[1,0,0,0,0,0,0,0;
         0,1,0,0,0,0,0,0;
         0,0,1,0,0,0,0,0;
         0,1,1,1,0,0,0,0;
         0,0,0,0,1,0,0,0;
         0,1,0,0,1,1,0,0;
         0,0,1,0,1,0,1,0;
         0,1,1,1,1,1,1,1;            
         ]*mass;
end