Inverse Gamma distribution
By tholscla on Thu, 12/05/2013 - 15:57
I hate loading whole libraries for quick one line distributions.
dinvgamma=function(x,a,b){exp(a*log(b) - lgamma(a) - (a+1)*log(x) - b*1.0/x)}
rinvgamma=function(n,a,b){1/rgamma(n,a,b)} #at one point the MCMCpack library has this function with different parameters for Windows and Unix