% MGD file mgd.m  Moment generating function for compound demand
% Version of 5/19/97
% Uses m-functions csort, mgsum
disp('Do not forget zeros coefficients for missing')
disp('powers in the generating function for N')
disp(' ') 
g  = input('Enter COEFFICIENTS for gN  ');
y  = input('Enter VALUES for Y  ');
p  = input('Enter PROBABILITIES for Y  ');
n  = length(g);               % Initialization
a  = 0;
b  = 1;
D  = a;
PD = g(1);
for i = 2:n
  [a,b] = mgsum(y,a,p,b);
  D  = [D a];
  PD = [PD b*g(i)];
  [D,PD] = csort(D,PD);
end
r = find(PD>1e-13); 
D = D(r);                     % Values with positive probability
PD = PD(r);                   % Corresponding probabilities
mD = [D; PD]';                % Display details
disp('Values are in row matrix D; probabilities are in PD.')
disp('To view the distribution, call for mD.')