Chi-Square random numbers
x = distfun_chi2rnd(k) x = distfun_chi2rnd(k,[m,n]) x = distfun_chi2rnd(k,m,n)
a matrix of doubles, the number of degrees of freedom, k>0 (can be non integer)
a 1-by-1 matrix of floating point integers, the number of rows of x
a 1-by-1 matrix of floating point integers, the number of columns of x
a matrix of doubles, the positive random numbers.
Generates random variables from the Chi-Square distribution function.
Any scalar input argument is expanded to a matrix of doubles of the same size as the other input arguments.
// Test with expanded k x = distfun_chi2rnd((1:6)') // Check x = distfun_chi2rnd(k,v) x = distfun_chi2rnd(2,[4 5]) // Check mean and variance N = 50000; k = 3; x = distfun_chi2rnd(k,[1 N]); Mx = mean(x) Vx = variance(x) [M,V] = distfun_chi2stat (k) // Compare histogram of random numbers // with PDF. k=5; scf(); x=distfun_chi2rnd(k,10000,1); histplot(30,x); x=linspace(0,25,1000); y=distfun_chi2pdf(x,k); plot(x,y,"b-"); xtitle("Chi-square random numbers","X","Density"); legend(["Empirical","PDF"]); | ![]() | ![]() |
http://en.wikipedia.org/wiki/Chi-squared_distribution