On Sat, 3 Nov 2012, Ben Gamari wrote:
My digamma package[1] implements an approximation to the digamma function (due to Tom Minka). Considering that the math-functions package already has a gamma implementation, it seems it would be natural to merge digamma into this package. Alternatively (or additionally), James Cook's gamma package also has a variety of gamma implementations and is also a candidate for merging digamma into.
I don't mind maintaining digamma, but it might be easier for others if there were a single package providing all of these functions. Do others have an opinion on this? Are either (or both) of you interested in picking up a digamma implementation?
Btw. I did some experiments with approximating the inverse of digamma and (exp . digamma). Just in case someone is interested in it: http://code.haskell.org/~thielema/htam/src/Numerics/Digamma.hs http://code.haskell.org/~thielema/htam/src/Numerics/Digamma/Inverse.hs http://code.haskell.org/~thielema/htam/src/Numerics/Digamma/Exponential.hs