Creates a random inverse wishart distribution when given degrees of freedom and a sigma matrix.
riwishart(df, S)A matrix that is an inverse wishart distribution.
#Call with the following data:
riwishart(3, diag(2))
#> [,1] [,2]
#> [1,] 0.74992047 0.02469748
#> [2,] 0.02469748 0.31627187