x = rf(n,df1,df2) Input n positive integer or a vector [lig,col] of integers df1,df2 degrees of freedom Output x n-vector or a n-matrix of random numbers chosen from Fisher-Snedecor distribution with df1 and df2 degrees of freedom (the F law with degrees of freedom df1 and df2 is the law of (X/df1)/(Y/df2) where X and Y are independent Chisquare random variables with one degree of freedom)