G_do_hoelder: fix the transformation of the imaginary part.

The G_do_hoelder function transforms the arguments as z -> 1-z.
If z has an imaginary part, the sign of the imagniary part transforms
as s -> -s.
In the special case where z is real and > 1, the transformed value is
real and < 0. For (transformed) real negative values of z the sign of
the imaginary part is not relevant (there are no branch cuts). The code
requires that in this case the sign takes the default value +1.
This is now fixed.

diff --git a/ginac/inifcns_nstdsums.cpp b/ginac/inifcns_nstdsums.cpp
index 62c6c62f2737cf6b87a34db73bc51060103c1ff5..9f1e2cf0a845e2005256533b76fbb1f45c82b7c5 100644 (file)
--- a/ginac/inifcns_nstdsums.cpp
+++ b/ginac/inifcns_nstdsums.cpp
@@ -1020,9 +1020,8 @@ G_do_hoelder(std::vector<cln::cl_N> x, /* yes, it's passed by value */
                std::vector<int> qlsts;
                for (std::size_t j = r; j >= 1; --j) {
                        qlstx.push_back(cln::cl_N(1) - x[j-1]);
-                       if (instanceof(x[j-1], cln::cl_R_ring) &&
-                           realpart(x[j-1]) > 1 && realpart(x[j-1]) <= 2) {
-                               qlsts.push_back(s[j-1]);
+                       if (instanceof(x[j-1], cln::cl_R_ring) && realpart(x[j-1]) > 1) {
+                               qlsts.push_back(1);
                        } else {
                                qlsts.push_back(-s[j-1]);
                        }