function [N] = Poisson(lambda,n);

%Generates a vector with n Poisson random variables, N, with mean lambda.

max=exp(-lambda);
N=ones(n,1);
for i=1:n
    u=rand;
    while(u>max)
        N(i)=N(i)+1;
        u=u*rand;
    end
    N(i)=N(i)-1;
end