RANDNF RANDNF Generate Noncentral F-Distribution Random Variable Usage Generates a vector of non-central F-distributed random variables with the specified parameters. The general syntax for its use is y = randnf(n,m,c) where n is the number of degrees of freedom in the numerator, and m is the number of degrees of freedom in the denominator. The vector c determines the non-centrality shift of the numerator.