### Fixed branch cut of polylog again

```This fixes the problem of 3b2d170d and bdc545ff
for good.

In the previous version I had a conjg in there,
but that turned out to be nonsense. To see why,
see the comment in 3b2d170d (spoiler alert: it has
to do with a peculiarity of IEEE 754)```
parent ff2c22d0
 ... ... @@ -400,6 +400,19 @@ CONTAINS END FUNCTION FUNCTION MYLOG(x) complex(kind=prec) :: x, mylog if (abs(aimag(x)) < zero) then if (real(x) > 0) then mylog = cmplx(log(real(+x,kind=prec)), kind=prec) else mylog = cmplx(log(real(-x,kind=prec)), pi, kind=prec) endif else mylog = log(x) endif END FUNCTION RECURSIVE FUNCTION polylog1(m,x) result(res) ! computes the polylog ... ... @@ -433,7 +446,7 @@ CONTAINS else if (abs(x) .gt. 1) then inv = 1._prec/x res = (-1)**(m-1)*polylog(m,inv) & - (2._prec*pi*i_)**m * bernoulli_polynomial(m, 0.5_prec-i_*log(-x)/2._prec/pi) / factorial(m) - (2._prec*pi*i_)**m * bernoulli_polynomial(m, 0.5_prec-i_*mylog(-x)/2._prec/pi) / factorial(m) else if(m == 2) then res = dilog(x) else if(m == 3) then ... ... @@ -489,7 +502,7 @@ CONTAINS plog1 = plog1 - b%i0*i_*pi endif else plog1 = log(1.-a%c/b%c) plog1 = mylog(1.-a%c/b%c) endif END FUNCTION ... ...
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