please note included graphic. The plot of Li2 is form software I wrote. The other of polylog (2,x) is a plot made from Anaconda data computed over the specified domain. The polylog looks like a bug to me. I checked the MPMATH code and found the analytic continuation boundary specified is 1.4 where coincidentally the polylog plot seems to go wrong. Please let me know if I have made mistakes or let know know thoughts of others. I have run tests several times so I think I have good analysis on this
my mistake, sorry… found my bug… oops