Poisson random numbers
R = distfun_poissrnd(lambda) R = distfun_poissrnd(lambda,[m,n]) R = distfun_poissrnd(lambda,m,n)
a matrix of doubles, the average rate of occurrence. lambda>0.
a 1-by-1 matrix of floating point integers, the number of rows of R
a 1-by-1 matrix of floating point integers, the number of columns of R
a matrix of doubles, the random numbers in the set {0,1,2,3,...}.
Generates random variables from the Poisson distribution function.
Any scalar input argument is expanded to a matrix of doubles of the same size as the other input arguments.
// set the initial seed for tests distfun_seedset(1); // Test with expanded lambda computed = distfun_poissrnd(1:6) expected = [1 7 4 7 0 3]; // Check expansion of lambda in R = distfun_poissrnd(lambda) distfun_seedset(1); computed = distfun_poissrnd([12 14 20]) expected = [11 24 20]; // Check R = distfun_poissrnd(lambda,v) computed = distfun_poissrnd(2,[4 5]) // Check mean and variance N = 50000; lambda = 13; computed = distfun_poissrnd(lambda,[1 N]); c = mean(computed(1:N)) d = st_deviation(computed(1:N) ) [M,V] = distfun_poissstat (lambda) // Check actual distribution lambda=12; N=10000; R=distfun_poissrnd(lambda,1,N); h=scf(); distfun_inthisto(R); h.children.children(1).children.background=-2; x=0:2*lambda; y=distfun_poisspdf(x,lambda); plot(x,y,"ro-"); xtitle("Poisson Random Numbers","X","Frequency") legend(["Empirical","Density"]); | ![]() | ![]() |
http://en.wikipedia.org/wiki/Poisson_distribution