They're pretty much completely different languages. If I have some free time (hah) I'll take a stab at converting it.
I think there is an R package that will do the integration. Would that be easier to implement than re-coding?
OK here's a JSL implementation of the Fortran code. The code runs, but you'll need to test it out to make sure the numbers are good. It's pretty much a straight conversion of the Fortran program. Interesting exercise!
This is incredible! It works flawlessly! This is certainly beer-worthy work, if you think of a way I can buy you one let me know