]> www.ginac.de Git - ginac.git/blobdiff - ginac/inifcns_nstdsums.cpp
multiple zeta values: make crandall_Y_loop helper function reentrant.
[ginac.git] / ginac / inifcns_nstdsums.cpp
index b1f227d0c3be5179ff5beec7be805efb2c3005c1..d85044d04bd1f311b2d26ad5ab8ccf0572d1ebe7 100644 (file)
@@ -18,7 +18,7 @@
  *      [Cra] Fast Evaluation of Multiple Zeta Sums, R.E.Crandall, Math.Comp. 67 (1998), pp. 1163-1172.
  *      [ReV] Harmonic Polylogarithms, E.Remiddi, J.A.M.Vermaseren, Int.J.Mod.Phys. A15 (2000), pp. 725-754
  *      [BBB] Special Values of Multiple Polylogarithms, J.Borwein, D.Bradley, D.Broadhurst, P.Lisonek, Trans.Amer.Math.Soc. 353/3 (2001), pp. 907-941
- *      [VSW] Numerical evalutation of multiple polylogarithms, J.Vollinga, S.Weinzierl
+ *      [VSW] Numerical evaluation of multiple polylogarithms, J.Vollinga, S.Weinzierl, hep-ph/0410259
  *
  *    - The order of parameters and arguments of Li and zeta is defined according to the nested sums
  *      representation. The parameters for H are understood as in [ReV]. They can be in expanded --- only
@@ -47,7 +47,7 @@
  */
 
 /*
- *  GiNaC Copyright (C) 1999-2004 Johannes Gutenberg University Mainz, Germany
+ *  GiNaC Copyright (C) 1999-2008 Johannes Gutenberg University Mainz, Germany
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -61,7 +61,7 @@
  *
  *  You should have received a copy of the GNU General Public License
  *  along with this program; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  */
 
 #include <sstream>
@@ -320,7 +320,7 @@ cln::cl_N Lin_do_sum_Xn(int n, const cln::cl_N& x)
 
 
 // forward declaration needed by function Li_projection and C below
-numeric S_num(int n, int p, const numeric& x);
+const cln::cl_N S_num(int n, int p, const cln::cl_N& x);
 
 
 // helper function for classical polylog Li
@@ -371,7 +371,7 @@ cln::cl_N Li_projection(int n, const cln::cl_N& x, const cln::float_format_t& pr
                } else {
                        cln::cl_N result = -cln::expt(cln::log(x), n-1) * cln::log(1-x) / cln::factorial(n-1);
                        for (int j=0; j<n-1; j++) {
-                               result = result + (S_num(n-j-1, 1, 1).to_cl_N() - S_num(1, n-j-1, 1-x).to_cl_N())
+                               result = result + (S_num(n-j-1, 1, 1) - S_num(1, n-j-1, 1-x))
                                                  * cln::expt(cln::log(x), j) / cln::factorial(j);
                        }
                        return result;
@@ -379,15 +379,14 @@ cln::cl_N Li_projection(int n, const cln::cl_N& x, const cln::float_format_t& pr
        }
 }
 
-
 // helper function for classical polylog Li
-numeric Lin_numeric(int n, const numeric& x)
+const cln::cl_N Lin_numeric(const int n, const cln::cl_N& x)
 {
        if (n == 1) {
                // just a log
-               return -cln::log(1-x.to_cl_N());
+               return -cln::log(1-x);
        }
-       if (x.is_zero()) {
+       if (zerop(x)) {
                return 0;
        }
        if (x == 1) {
@@ -398,12 +397,11 @@ numeric Lin_numeric(int n, const numeric& x)
                // [Kol] (2.22)
                return -(1-cln::expt(cln::cl_I(2),1-n)) * cln::zeta(n);
        }
-       if (abs(x.real()) < 0.4 && abs(abs(x)-1) < 0.01) {
-               cln::cl_N x_ = ex_to<numeric>(x).to_cl_N();
-               cln::cl_N result = -cln::expt(cln::log(x_), n-1) * cln::log(1-x_) / cln::factorial(n-1);
+       if (cln::abs(realpart(x)) < 0.4 && cln::abs(cln::abs(x)-1) < 0.01) {
+               cln::cl_N result = -cln::expt(cln::log(x), n-1) * cln::log(1-x) / cln::factorial(n-1);
                for (int j=0; j<n-1; j++) {
-                       result = result + (S_num(n-j-1, 1, 1).to_cl_N() - S_num(1, n-j-1, 1-x_).to_cl_N())
-                               * cln::expt(cln::log(x_), j) / cln::factorial(j);
+                       result = result + (S_num(n-j-1, 1, 1) - S_num(1, n-j-1, 1-x))
+                               * cln::expt(cln::log(x), j) / cln::factorial(j);
                }
                return result;
        }
@@ -411,11 +409,11 @@ numeric Lin_numeric(int n, const numeric& x)
        // what is the desired float format?
        // first guess: default format
        cln::float_format_t prec = cln::default_float_format;
-       const cln::cl_N value = x.to_cl_N();
+       const cln::cl_N value = x;
        // second guess: the argument's format
-       if (!x.real().is_rational())
+       if (!instanceof(realpart(x), cln::cl_RA_ring))
                prec = cln::float_format(cln::the<cln::cl_F>(cln::realpart(value)));
-       else if (!x.imag().is_rational())
+       else if (!instanceof(imagpart(x), cln::cl_RA_ring))
                prec = cln::float_format(cln::the<cln::cl_F>(cln::imagpart(value)));
        
        // [Kol] (5.15)
@@ -441,7 +439,7 @@ numeric Lin_numeric(int n, const numeric& x)
                cln::cl_N add;
                for (int j=0; j<n-1; j++) {
                        add = add + (1+cln::expt(cln::cl_I(-1),n-j)) * (1-cln::expt(cln::cl_I(2),1-n+j))
-                                   * Lin_numeric(n-j,1).to_cl_N() * cln::expt(cln::log(-value),j) / cln::factorial(j);
+                                   * Lin_numeric(n-j,1) * cln::expt(cln::log(-value),j) / cln::factorial(j);
                }
                result = result - add;
                return result;
@@ -471,7 +469,13 @@ namespace {
 // performs the actual series summation for multiple polylogarithms
 cln::cl_N multipleLi_do_sum(const std::vector<int>& s, const std::vector<cln::cl_N>& x)
 {
+       // ensure all x <> 0.
+       for (std::vector<cln::cl_N>::const_iterator it = x.begin(); it != x.end(); ++it) {
+               if ( *it == 0 ) return cln::cl_float(0, cln::float_format(Digits));
+       }
+
        const int j = s.size();
+       bool flag_accidental_zero = false;
 
        std::vector<cln::cl_N> t(j);
        cln::cl_F one = cln::cl_float(1, cln::float_format(Digits));
@@ -480,19 +484,18 @@ cln::cl_N multipleLi_do_sum(const std::vector<int>& s, const std::vector<cln::cl
        int q = 0;
        do {
                t0buf = t[0];
-               // do it once ...
                q++;
                t[j-1] = t[j-1] + cln::expt(x[j-1], q) / cln::expt(cln::cl_I(q),s[j-1]) * one;
                for (int k=j-2; k>=0; k--) {
                        t[k] = t[k] + t[k+1] * cln::expt(x[k], q+j-1-k) / cln::expt(cln::cl_I(q+j-1-k), s[k]);
                }
-               // ... and do it again (to avoid premature drop out due to special arguments)
                q++;
                t[j-1] = t[j-1] + cln::expt(x[j-1], q) / cln::expt(cln::cl_I(q),s[j-1]) * one;
                for (int k=j-2; k>=0; k--) {
+                       flag_accidental_zero = cln::zerop(t[k+1]);
                        t[k] = t[k] + t[k+1] * cln::expt(x[k], q+j-1-k) / cln::expt(cln::cl_I(q+j-1-k), s[k]);
                }
-       } while (t[0] != t0buf);
+       } while ( (t[0] != t0buf) || cln::zerop(t[0]) || flag_accidental_zero );
 
        return t[0];
 }
@@ -515,16 +518,12 @@ cln::cl_N mLi_do_summation(const lst& m, const lst& x)
 lst convert_parameter_Li_to_H(const lst& m, const lst& x, ex& pf);
 
 
-// holding dummy-symbols for the G/Li transformations
-std::vector<ex> gsyms;
-
-
 // type used by the transformation functions for G
 typedef std::vector<int> Gparameter;
 
 
 // G_eval1-function for G transformations
-ex G_eval1(int a, int scale)
+ex G_eval1(int a, int scale, const exvector& gsyms)
 {
        if (a != 0) {
                const ex& scs = gsyms[std::abs(scale)];
@@ -541,7 +540,7 @@ ex G_eval1(int a, int scale)
 
 
 // G_eval-function for G transformations
-ex G_eval(const Gparameter& a, int scale)
+ex G_eval(const Gparameter& a, int scale, const exvector& gsyms)
 {
        // check for properties of G
        ex sc = gsyms[std::abs(scale)];
@@ -575,7 +574,7 @@ ex G_eval(const Gparameter& a, int scale)
                for (; it != a.end(); ++it) {
                        short_a.push_back(*it);
                }
-               ex result = G_eval1(a.front(), scale) * G_eval(short_a, scale);
+               ex result = G_eval1(a.front(), scale, gsyms) * G_eval(short_a, scale, gsyms);
                it = short_a.begin();
                for (int i=1; i<count_ones; ++i) {
                        ++it;
@@ -593,14 +592,14 @@ ex G_eval(const Gparameter& a, int scale)
                        for (; it2 != short_a.end(); ++it2) {
                                newa.push_back(*it2);   
                        }
-                       result -= G_eval(newa, scale);
+                       result -= G_eval(newa, scale, gsyms);
                }
                return result / count_ones;
        }
 
        // G({1,...,1};y) -> G({1};y)^k / k!
        if (all_ones && a.size() > 1) {
-               return pow(G_eval1(a.front(),scale), count_ones) / factorial(count_ones);
+               return pow(G_eval1(a.front(),scale, gsyms), count_ones) / factorial(count_ones);
        }
 
        // G({0,...,0};y) -> log(y)^k / k!
@@ -693,7 +692,7 @@ Gparameter prepare_pending_integrals(const Gparameter& pending_integrals, int sc
 
 
 // handles trailing zeroes for an otherwise convergent integral
-ex trailing_zeros_G(const Gparameter& a, int scale)
+ex trailing_zeros_G(const Gparameter& a, int scale, const exvector& gsyms)
 {
        bool convergent;
        int depth, trailing_zeros;
@@ -705,23 +704,23 @@ ex trailing_zeros_G(const Gparameter& a, int scale)
        if ((trailing_zeros > 0) && (depth > 0)) {
                ex result;
                Gparameter new_a(a.begin(), a.end()-1);
-               result += G_eval1(0, scale) * trailing_zeros_G(new_a, scale);
+               result += G_eval1(0, scale, gsyms) * trailing_zeros_G(new_a, scale, gsyms);
                for (Gparameter::const_iterator it = a.begin(); it != last; ++it) {
                        Gparameter new_a(a.begin(), it);
                        new_a.push_back(0);
                        new_a.insert(new_a.end(), it, a.end()-1);
-                       result -= trailing_zeros_G(new_a, scale);
+                       result -= trailing_zeros_G(new_a, scale, gsyms);
                }
 
                return result / trailing_zeros;
        } else {
-               return G_eval(a, scale);
+               return G_eval(a, scale, gsyms);
        }
 }
 
 
 // G transformation [VSW] (57),(58)
-ex depth_one_trafo_G(const Gparameter& pending_integrals, const Gparameter& a, int scale)
+ex depth_one_trafo_G(const Gparameter& pending_integrals, const Gparameter& a, int scale, const exvector& gsyms)
 {
        // pendint = ( y1, b1, ..., br )
        //       a = ( 0, ..., 0, amin )
@@ -752,15 +751,21 @@ ex depth_one_trafo_G(const Gparameter& pending_integrals, const Gparameter& a, i
                        result -= I*Pi;
                }
                if (psize) {
-                       result *= trailing_zeros_G(convert_pending_integrals_G(pending_integrals), pending_integrals.front());
+                       result *= trailing_zeros_G(convert_pending_integrals_G(pending_integrals),
+                                                  pending_integrals.front(),
+                                                  gsyms);
                }
                
                // G(y2_{-+}; sr)
-               result += trailing_zeros_G(convert_pending_integrals_G(new_pending_integrals), new_pending_integrals.front());
+               result += trailing_zeros_G(convert_pending_integrals_G(new_pending_integrals),
+                                          new_pending_integrals.front(),
+                                          gsyms);
                
                // G(0; sr)
                new_pending_integrals.back() = 0;
-               result -= trailing_zeros_G(convert_pending_integrals_G(new_pending_integrals), new_pending_integrals.front());
+               result -= trailing_zeros_G(convert_pending_integrals_G(new_pending_integrals),
+                                          new_pending_integrals.front(),
+                                          gsyms);
 
                return result;
        }
@@ -772,14 +777,16 @@ ex depth_one_trafo_G(const Gparameter& pending_integrals, const Gparameter& a, i
        //term zeta_m
        result -= zeta(a.size());
        if (psize) {
-               result *= trailing_zeros_G(convert_pending_integrals_G(pending_integrals), pending_integrals.front());
+               result *= trailing_zeros_G(convert_pending_integrals_G(pending_integrals),
+                                          pending_integrals.front(),
+                                          gsyms);
        }
        
        // term int_0^sr dt/t G_{m-1}( (1/y2)_{+-}; 1/t )
        //    = int_0^sr dt/t G_{m-1}( t_{+-}; y2 )
        Gparameter new_a(a.begin()+1, a.end());
        new_pending_integrals.push_back(0);
-       result -= depth_one_trafo_G(new_pending_integrals, new_a, scale);
+       result -= depth_one_trafo_G(new_pending_integrals, new_a, scale, gsyms);
        
        // term int_0^y2 dt/t G_{m-1}( (1/y2)_{+-}; 1/t )
        //    = int_0^y2 dt/t G_{m-1}( t_{+-}; y2 )
@@ -787,10 +794,12 @@ ex depth_one_trafo_G(const Gparameter& pending_integrals, const Gparameter& a, i
        new_pending_integrals_2.push_back(scale);
        new_pending_integrals_2.push_back(0);
        if (psize) {
-               result += trailing_zeros_G(convert_pending_integrals_G(pending_integrals), pending_integrals.front())
-                         * depth_one_trafo_G(new_pending_integrals_2, new_a, scale);
+               result += trailing_zeros_G(convert_pending_integrals_G(pending_integrals),
+                                          pending_integrals.front(),
+                                          gsyms)
+                         * depth_one_trafo_G(new_pending_integrals_2, new_a, scale, gsyms);
        } else {
-               result += depth_one_trafo_G(new_pending_integrals_2, new_a, scale);
+               result += depth_one_trafo_G(new_pending_integrals_2, new_a, scale, gsyms);
        }
 
        return result;
@@ -799,11 +808,13 @@ ex depth_one_trafo_G(const Gparameter& pending_integrals, const Gparameter& a, i
 
 // forward declaration
 ex shuffle_G(const Gparameter & a0, const Gparameter & a1, const Gparameter & a2,
-            const Gparameter& pendint, const Gparameter& a_old, int scale);
+            const Gparameter& pendint, const Gparameter& a_old, int scale,
+            const exvector& gsyms);
 
 
 // G transformation [VSW]
-ex G_transform(const Gparameter& pendint, const Gparameter& a, int scale)
+ex G_transform(const Gparameter& pendint, const Gparameter& a, int scale,
+              const exvector& gsyms)
 {
        // main recursion routine
        //
@@ -829,10 +840,12 @@ ex G_transform(const Gparameter& pendint, const Gparameter& a, int scale)
                if (a.size() == 0) {
                  result = 1;
                } else {
-                 result = G_eval(a, scale);
+                 result = G_eval(a, scale, gsyms);
                }
                if (pendint.size() > 0) {
-                 result *= trailing_zeros_G(convert_pending_integrals_G(pendint), pendint.front());
+                 result *= trailing_zeros_G(convert_pending_integrals_G(pendint),
+                                            pendint.front(),
+                                            gsyms);
                } 
                return result;
        }
@@ -841,12 +854,12 @@ ex G_transform(const Gparameter& pendint, const Gparameter& a, int scale)
        if (trailing_zeros > 0) {
                ex result;
                Gparameter new_a(a.begin(), a.end()-1);
-               result += G_eval1(0, scale) * G_transform(pendint, new_a, scale);
+               result += G_eval1(0, scale, gsyms) * G_transform(pendint, new_a, scale, gsyms);
                for (Gparameter::const_iterator it = a.begin(); it != firstzero; ++it) {
                        Gparameter new_a(a.begin(), it);
                        new_a.push_back(0);
                        new_a.insert(new_a.end(), it, a.end()-1);
-                       result -= G_transform(pendint, new_a, scale);
+                       result -= G_transform(pendint, new_a, scale, gsyms);
                }
                return result / trailing_zeros;
        }
@@ -854,15 +867,17 @@ ex G_transform(const Gparameter& pendint, const Gparameter& a, int scale)
        // convergence case
        if (convergent) {
                if (pendint.size() > 0) {
-                       return G_eval(convert_pending_integrals_G(pendint), pendint.front()) * G_eval(a, scale);
+                       return G_eval(convert_pending_integrals_G(pendint),
+                                     pendint.front(), gsyms)*
+                               G_eval(a, scale, gsyms);
                } else {
-                       return G_eval(a, scale);
+                       return G_eval(a, scale, gsyms);
                }
        }
 
        // call basic transformation for depth equal one
        if (depth == 1) {
-               return depth_one_trafo_G(pendint, a, scale);
+               return depth_one_trafo_G(pendint, a, scale, gsyms);
        }
 
        // do recursion
@@ -877,9 +892,10 @@ ex G_transform(const Gparameter& pendint, const Gparameter& a, int scale)
                Gparameter a1(a.begin(),min_it+1);
                Gparameter a2(min_it+1,a.end());
 
-               ex result = G_transform(pendint,a2,scale)*G_transform(empty,a1,scale);
+               ex result = G_transform(pendint, a2, scale, gsyms)*
+                       G_transform(empty, a1, scale, gsyms);
 
-               result -= shuffle_G(empty,a1,a2,pendint,a,scale);
+               result -= shuffle_G(empty, a1, a2, pendint, a, scale, gsyms);
                return result;
        }
 
@@ -890,9 +906,10 @@ ex G_transform(const Gparameter& pendint, const Gparameter& a, int scale)
        Gparameter new_pendint = prepare_pending_integrals(pendint, a[min_it_pos]);
        Gparameter new_a = a;
        new_a[min_it_pos] = 0;
-       ex result = G_transform(empty, new_a, scale);
+       ex result = G_transform(empty, new_a, scale, gsyms);
        if (pendint.size() > 0) {
-               result *= trailing_zeros_G(convert_pending_integrals_G(pendint), pendint.front());
+               result *= trailing_zeros_G(convert_pending_integrals_G(pendint),
+                                          pendint.front(), gsyms);
        }
 
        // other terms
@@ -901,29 +918,33 @@ ex G_transform(const Gparameter& pendint, const Gparameter& a, int scale)
        if (changeit != new_a.begin()) {
                // smallest in the middle
                new_pendint.push_back(*changeit);
-               result -= trailing_zeros_G(convert_pending_integrals_G(new_pendint), new_pendint.front())
-                       * G_transform(empty, new_a, scale);
+               result -= trailing_zeros_G(convert_pending_integrals_G(new_pendint),
+                                          new_pendint.front(), gsyms)*
+                       G_transform(empty, new_a, scale, gsyms);
                int buffer = *changeit;
                *changeit = *min_it;
-               result += G_transform(new_pendint, new_a, scale);
+               result += G_transform(new_pendint, new_a, scale, gsyms);
                *changeit = buffer;
                new_pendint.pop_back();
                --changeit;
                new_pendint.push_back(*changeit);
-               result += trailing_zeros_G(convert_pending_integrals_G(new_pendint), new_pendint.front())
-                       * G_transform(empty, new_a, scale);
+               result += trailing_zeros_G(convert_pending_integrals_G(new_pendint),
+                                          new_pendint.front(), gsyms)*
+                       G_transform(empty, new_a, scale, gsyms);
                *changeit = *min_it;
-               result -= G_transform(new_pendint, new_a, scale);
+               result -= G_transform(new_pendint, new_a, scale, gsyms);
        } else {
                // smallest at the front
                new_pendint.push_back(scale);
-               result += trailing_zeros_G(convert_pending_integrals_G(new_pendint), new_pendint.front())
-                       * G_transform(empty, new_a, scale);
+               result += trailing_zeros_G(convert_pending_integrals_G(new_pendint),
+                                          new_pendint.front(), gsyms)*
+                       G_transform(empty, new_a, scale, gsyms);
                new_pendint.back() =  *changeit;
-               result -= trailing_zeros_G(convert_pending_integrals_G(new_pendint), new_pendint.front())
-                       * G_transform(empty, new_a, scale);
+               result -= trailing_zeros_G(convert_pending_integrals_G(new_pendint),
+                                          new_pendint.front(), gsyms)*
+                       G_transform(empty, new_a, scale, gsyms);
                *changeit = *min_it;
-               result += G_transform(new_pendint, new_a, scale);
+               result += G_transform(new_pendint, new_a, scale, gsyms);
        }
        return result;
 }
@@ -932,27 +953,28 @@ ex G_transform(const Gparameter& pendint, const Gparameter& a, int scale)
 // shuffles the two parameter list a1 and a2 and calls G_transform for every term except
 // for the one that is equal to a_old
 ex shuffle_G(const Gparameter & a0, const Gparameter & a1, const Gparameter & a2,
-            const Gparameter& pendint, const Gparameter& a_old, int scale) 
+            const Gparameter& pendint, const Gparameter& a_old, int scale,
+            const exvector& gsyms) 
 {
        if (a1.size()==0 && a2.size()==0) {
                // veto the one configuration we don't want
                if ( a0 == a_old ) return 0;
 
-               return G_transform(pendint,a0,scale);
+               return G_transform(pendint, a0, scale, gsyms);
        }
 
        if (a2.size()==0) {
                Gparameter empty;
                Gparameter aa0 = a0;
                aa0.insert(aa0.end(),a1.begin(),a1.end());
-               return shuffle_G(aa0,empty,empty,pendint,a_old,scale);
+               return shuffle_G(aa0, empty, empty, pendint, a_old, scale, gsyms);
        }
 
        if (a1.size()==0) {
                Gparameter empty;
                Gparameter aa0 = a0;
                aa0.insert(aa0.end(),a2.begin(),a2.end());
-               return shuffle_G(aa0,empty,empty,pendint,a_old,scale);
+               return shuffle_G(aa0, empty, empty, pendint, a_old, scale, gsyms);
        }
 
        Gparameter a1_removed(a1.begin()+1,a1.end());
@@ -964,8 +986,8 @@ ex shuffle_G(const Gparameter & a0, const Gparameter & a1, const Gparameter & a2
        a01.push_back( a1[0] );
        a02.push_back( a2[0] );
 
-       return shuffle_G(a01,a1_removed,a2,pendint,a_old,scale)
-            + shuffle_G(a02,a1,a2_removed,pendint,a_old,scale);
+       return shuffle_G(a01, a1_removed, a2, pendint, a_old, scale, gsyms)
+            + shuffle_G(a02, a1, a2_removed, pendint, a_old, scale, gsyms);
 }
 
 
@@ -980,9 +1002,8 @@ ex G_numeric(const lst& x, const lst& s, const ex& y)
        for (lst::const_iterator it = x.begin(); it != x.end(); ++it) {
                if (!(*it).is_zero()) {
                        ++depth;
-                       if (abs(*it) - y < -pow(10,-Digits+2)) {
+                       if (abs(*it) - y < -pow(10,-Digits+1)) {
                                need_trafo = true;
-                               break;
                        }
                        if (abs((abs(*it) - y)/y) < 0.01) {
                                need_hoelder = true;
@@ -992,10 +1013,62 @@ ex G_numeric(const lst& x, const lst& s, const ex& y)
        if (x.op(x.nops()-1).is_zero()) {
                need_trafo = true;
        }
-       if (depth == 1 && !need_trafo) {
+       if (depth == 1 && x.nops() == 2 && !need_trafo) {
                return -Li(x.nops(), y / x.op(x.nops()-1)).evalf();
        }
        
+       // do acceleration transformation (hoelder convolution [BBB])
+       if (need_hoelder) {
+               
+               ex result;
+               const int size = x.nops();
+               lst newx;
+               for (lst::const_iterator it = x.begin(); it != x.end(); ++it) {
+                       newx.append(*it / y);
+               }
+               
+               for (int r=0; r<=size; ++r) {
+                       ex buffer = pow(-1, r);
+                       ex p = 2;
+                       bool adjustp;
+                       do {
+                               adjustp = false;
+                               for (lst::const_iterator it = newx.begin(); it != newx.end(); ++it) {
+                                       if (*it == 1/p) {
+                                               p += (3-p)/2; 
+                                               adjustp = true;
+                                               continue;
+                                       }
+                               }
+                       } while (adjustp);
+                       ex q = p / (p-1);
+                       lst qlstx;
+                       lst qlsts;
+                       for (int j=r; j>=1; --j) {
+                               qlstx.append(1-newx.op(j-1));
+                               if (newx.op(j-1).info(info_flags::real) && newx.op(j-1) > 1 && newx.op(j-1) <= 2) {
+                                       qlsts.append( s.op(j-1));
+                               } else {
+                                       qlsts.append( -s.op(j-1));
+                               }
+                       }
+                       if (qlstx.nops() > 0) {
+                               buffer *= G_numeric(qlstx, qlsts, 1/q);
+                       }
+                       lst plstx;
+                       lst plsts;
+                       for (int j=r+1; j<=size; ++j) {
+                               plstx.append(newx.op(j-1));
+                               plsts.append(s.op(j-1));
+                       }
+                       if (plstx.nops() > 0) {
+                               buffer *= G_numeric(plstx, plsts, 1/p);
+                       }
+                       result += buffer;
+               }
+               return result;
+       }
+       
        // convergence transformation
        if (need_trafo) {
 
@@ -1013,7 +1086,8 @@ ex G_numeric(const lst& x, const lst& s, const ex& y)
 
                // generate missing dummy-symbols
                int i = 1;
-               gsyms.clear();
+               // holding dummy-symbols for the G/Li transformations
+               exvector gsyms;
                gsyms.push_back(symbol("GSYMS_ERROR"));
                ex lastentry;
                for (std::multimap<ex,int>::const_iterator it = sortmap.begin(); it != sortmap.end(); ++it) {
@@ -1063,7 +1137,7 @@ ex G_numeric(const lst& x, const lst& s, const ex& y)
 
                // do transformation
                Gparameter pendint;
-               ex result = G_transform(pendint, a, scale);
+               ex result = G_transform(pendint, a, scale, gsyms);
                // replace dummy symbols with their values
                result = result.eval().expand();
                result = result.subs(subslst).evalf();
@@ -1071,58 +1145,6 @@ ex G_numeric(const lst& x, const lst& s, const ex& y)
                return result;
        }
 
-       // do acceleration transformation (hoelder convolution [BBB])
-       if (need_hoelder) {
-               
-               ex result;
-               const int size = x.nops();
-               lst newx;
-               for (lst::const_iterator it = x.begin(); it != x.end(); ++it) {
-                       newx.append(*it / y);
-               }
-               
-               for (int r=0; r<=size; ++r) {
-                       ex buffer = pow(-1, r);
-                       ex p = 2;
-                       bool adjustp;
-                       do {
-                               adjustp = false;
-                               for (lst::const_iterator it = newx.begin(); it != newx.end(); ++it) {
-                                       if (*it == 1/p) {
-                                               p += (3-p)/2; 
-                                               adjustp = true;
-                                               continue;
-                                       }
-                               }
-                       } while (adjustp);
-                       ex q = p / (p-1);
-                       lst qlstx;
-                       lst qlsts;
-                       for (int j=r; j>=1; --j) {
-                               qlstx.append(1-newx.op(j-1));
-                               if (newx.op(j-1).info(info_flags::real) && newx.op(j-1) > 1 && newx.op(j-1) <= 2) {
-                                       qlsts.append( s.op(j-1));
-                               } else {
-                                       qlsts.append( -s.op(j-1));
-                               }
-                       }
-                       if (qlstx.nops() > 0) {
-                               buffer *= G_numeric(qlstx, qlsts, 1/q);
-                       }
-                       lst plstx;
-                       lst plsts;
-                       for (int j=r+1; j<=size; ++j) {
-                               plstx.append(newx.op(j-1));
-                               plsts.append(s.op(j-1));
-                       }
-                       if (plstx.nops() > 0) {
-                               buffer *= G_numeric(plstx, plsts, 1/p);
-                       }
-                       result += buffer;
-               }
-               return result;
-       }
-       
        // do summation
        lst newx;
        lst m;
@@ -1197,7 +1219,12 @@ static ex G2_evalf(const ex& x_, const ex& y)
                if (*it != _ex0) {
                        all_zero = false;
                }
-               s.append(+1);
+               if ( !ex_to<numeric>(*it).is_real() && ex_to<numeric>(*it).imag() < 0 ) {
+                       s.append(-1);
+               }
+               else {
+                       s.append(+1);
+               }
        }
        if (all_zero) {
                return pow(log(y), x.nops()) / factorial(x.nops());
@@ -1233,7 +1260,12 @@ static ex G2_eval(const ex& x_, const ex& y)
                if (*it != _ex0) {
                        all_zero = false;
                }
-               s.append(+1);
+               if ( !ex_to<numeric>(*it).is_real() && ex_to<numeric>(*it).imag() < 0 ) {
+                       s.append(-1);
+               }
+               else {
+                       s.append(+1);
+               }
        }
        if (all_zero) {
                return pow(log(y), x.nops()) / factorial(x.nops());
@@ -1286,10 +1318,21 @@ static ex G3_evalf(const ex& x_, const ex& s_, const ex& y)
                if (*itx != _ex0) {
                        all_zero = false;
                }
-               if (*its >= 0) {
-                       sn.append(+1);
-               } else {
-                       sn.append(-1);
+               if ( ex_to<numeric>(*itx).is_real() ) {
+                       if ( *its >= 0 ) {
+                               sn.append(+1);
+                       }
+                       else {
+                               sn.append(-1);
+                       }
+               }
+               else {
+                       if ( ex_to<numeric>(*itx).imag() > 0 ) {
+                               sn.append(+1);
+                       }
+                       else {
+                               sn.append(-1);
+                       }
                }
        }
        if (all_zero) {
@@ -1333,10 +1376,21 @@ static ex G3_eval(const ex& x_, const ex& s_, const ex& y)
                if (*itx != _ex0) {
                        all_zero = false;
                }
-               if (*its >= 0) {
-                       sn.append(+1);
-               } else {
-                       sn.append(-1);
+               if ( ex_to<numeric>(*itx).is_real() ) {
+                       if ( *its >= 0 ) {
+                               sn.append(+1);
+                       }
+                       else {
+                               sn.append(-1);
+                       }
+               }
+               else {
+                       if ( ex_to<numeric>(*itx).imag() > 0 ) {
+                               sn.append(+1);
+                       }
+                       else {
+                               sn.append(-1);
+                       }
                }
        }
        if (all_zero) {
@@ -1376,12 +1430,18 @@ static ex Li_evalf(const ex& m_, const ex& x_)
        // classical polylogs
        if (m_.info(info_flags::posint)) {
                if (x_.info(info_flags::numeric)) {
-                       return Lin_numeric(ex_to<numeric>(m_).to_int(), ex_to<numeric>(x_));
+                       int m__ = ex_to<numeric>(m_).to_int();
+                       const cln::cl_N x__ = ex_to<numeric>(x_).to_cl_N();
+                       const cln::cl_N result = Lin_numeric(m__, x__);
+                       return numeric(result);
                } else {
                        // try to numerically evaluate second argument
                        ex x_val = x_.evalf();
                        if (x_val.info(info_flags::numeric)) {
-                               return Lin_numeric(ex_to<numeric>(m_).to_int(), ex_to<numeric>(x_val));
+                               int m__ = ex_to<numeric>(m_).to_int();
+                               const cln::cl_N x__ = ex_to<numeric>(x_val).to_cl_N();
+                               const cln::cl_N result = Lin_numeric(m__, x__);
+                               return numeric(result);
                        }
                }
        }
@@ -1495,7 +1555,10 @@ static ex Li_eval(const ex& m_, const ex& x_)
                }
        }
        if (m_.info(info_flags::posint) && x_.info(info_flags::numeric) && !x_.info(info_flags::crational)) {
-               return Lin_numeric(ex_to<numeric>(m_).to_int(), ex_to<numeric>(x_));
+               int m__ = ex_to<numeric>(m_).to_int();
+               const cln::cl_N x__ = ex_to<numeric>(x_).to_cl_N();
+               const cln::cl_N result = Lin_numeric(m__, x__);
+               return numeric(result);
        }
 
        return Li(m_, x_).hold();
@@ -1504,9 +1567,37 @@ static ex Li_eval(const ex& m_, const ex& x_)
 
 static ex Li_series(const ex& m, const ex& x, const relational& rel, int order, unsigned options)
 {
-       epvector seq;
-       seq.push_back(expair(Li(m, x), 0));
-       return pseries(rel, seq);
+       if (is_a<lst>(m) || is_a<lst>(x)) {
+               // multiple polylog
+               epvector seq;
+               seq.push_back(expair(Li(m, x), 0));
+               return pseries(rel, seq);
+       }
+       
+       // classical polylog
+       const ex x_pt = x.subs(rel, subs_options::no_pattern);
+       if (m.info(info_flags::numeric) && x_pt.info(info_flags::numeric)) {
+               // First special case: x==0 (derivatives have poles)
+               if (x_pt.is_zero()) {
+                       const symbol s;
+                       ex ser;
+                       // manually construct the primitive expansion
+                       for (int i=1; i<order; ++i)
+                               ser += pow(s,i) / pow(numeric(i), m);
+                       // substitute the argument's series expansion
+                       ser = ser.subs(s==x.series(rel, order), subs_options::no_pattern);
+                       // maybe that was terminating, so add a proper order term
+                       epvector nseq;
+                       nseq.push_back(expair(Order(_ex1), order));
+                       ser += pseries(rel, nseq);
+                       // reexpanding it will collapse the series again
+                       return ser.series(rel, order);
+               }
+               // TODO special cases: x==1 (branch point) and x real, >=1 (branch cut)
+               throw std::runtime_error("Li_series: don't know how to do the series expansion at this point!");
+       }
+       // all other cases should be safe, by now:
+       throw do_taylor();  // caught by function::series()
 }
 
 
@@ -1688,10 +1779,10 @@ cln::cl_N C(int n, int p)
                        if (k == 0) {
                                if (n & 1) {
                                        if (j & 1) {
-                                               result = result - 2 * cln::expt(cln::pi(),2*j) * S_num(n-2*j,p,1).to_cl_N() / cln::factorial(2*j);
+                                               result = result - 2 * cln::expt(cln::pi(),2*j) * S_num(n-2*j,p,1) / cln::factorial(2*j);
                                        }
                                        else {
-                                               result = result + 2 * cln::expt(cln::pi(),2*j) * S_num(n-2*j,p,1).to_cl_N() / cln::factorial(2*j);
+                                               result = result + 2 * cln::expt(cln::pi(),2*j) * S_num(n-2*j,p,1) / cln::factorial(2*j);
                                        }
                                }
                        }
@@ -1699,23 +1790,23 @@ cln::cl_N C(int n, int p)
                                if (k & 1) {
                                        if (j & 1) {
                                                result = result + cln::factorial(n+k-1)
-                                                                 * cln::expt(cln::pi(),2*j) * S_num(n+k-2*j,p-k,1).to_cl_N()
+                                                                 * cln::expt(cln::pi(),2*j) * S_num(n+k-2*j,p-k,1)
                                                                  / (cln::factorial(k) * cln::factorial(n-1) * cln::factorial(2*j));
                                        }
                                        else {
                                                result = result - cln::factorial(n+k-1)
-                                                                 * cln::expt(cln::pi(),2*j) * S_num(n+k-2*j,p-k,1).to_cl_N()
+                                                                 * cln::expt(cln::pi(),2*j) * S_num(n+k-2*j,p-k,1)
                                                                  / (cln::factorial(k) * cln::factorial(n-1) * cln::factorial(2*j));
                                        }
                                }
                                else {
                                        if (j & 1) {
-                                               result = result - cln::factorial(n+k-1) * cln::expt(cln::pi(),2*j) * S_num(n+k-2*j,p-k,1).to_cl_N()
+                                               result = result - cln::factorial(n+k-1) * cln::expt(cln::pi(),2*j) * S_num(n+k-2*j,p-k,1)
                                                                  / (cln::factorial(k) * cln::factorial(n-1) * cln::factorial(2*j));
                                        }
                                        else {
                                                result = result + cln::factorial(n+k-1)
-                                                                 * cln::expt(cln::pi(),2*j) * S_num(n+k-2*j,p-k,1).to_cl_N()
+                                                                 * cln::expt(cln::pi(),2*j) * S_num(n+k-2*j,p-k,1)
                                                                  / (cln::factorial(k) * cln::factorial(n-1) * cln::factorial(2*j));
                                        }
                                }
@@ -1777,10 +1868,20 @@ cln::cl_N b_k(int k)
 // helper function for S(n,p,x)
 cln::cl_N S_do_sum(int n, int p, const cln::cl_N& x, const cln::float_format_t& prec)
 {
+       static cln::float_format_t oldprec = cln::default_float_format;
+
        if (p==1) {
                return Li_projection(n+1, x, prec);
        }
-       
+
+       // precision has changed, we need to clear lookup table Yn
+       if ( oldprec != prec ) {
+               Yn.clear();
+               ynsize = 0;
+               ynlength = 100;
+               oldprec = prec;
+       }
+               
        // check if precalculated values are sufficient
        if (p > ynsize+1) {
                for (int i=ynsize; i<p-1; i++) {
@@ -1828,7 +1929,7 @@ cln::cl_N S_projection(int n, int p, const cln::cl_N& x, const cln::float_format
                                res2 = res2 + cln::expt(cln::cl_I(-1),r) * cln::expt(cln::log(1-x),r)
                                              * S_do_sum(p-r,n-s,1-x,prec) / cln::factorial(r);
                        }
-                       result = result + cln::expt(cln::log(x),s) * (S_num(n-s,p,1).to_cl_N() - res2) / cln::factorial(s);
+                       result = result + cln::expt(cln::log(x),s) * (S_num(n-s,p,1) - res2) / cln::factorial(s);
                }
 
                return result;
@@ -1839,7 +1940,7 @@ cln::cl_N S_projection(int n, int p, const cln::cl_N& x, const cln::float_format
 
 
 // helper function for S(n,p,x)
-numeric S_num(int n, int p, const numeric& x)
+const cln::cl_N S_num(int n, int p, const cln::cl_N& x)
 {
        if (x == 1) {
                if (n == 1) {
@@ -1875,15 +1976,15 @@ numeric S_num(int n, int p, const numeric& x)
        // what is the desired float format?
        // first guess: default format
        cln::float_format_t prec = cln::default_float_format;
-       const cln::cl_N value = x.to_cl_N();
+       const cln::cl_N value = x;
        // second guess: the argument's format
-       if (!x.real().is_rational())
+       if (!instanceof(realpart(value), cln::cl_RA_ring))
                prec = cln::float_format(cln::the<cln::cl_F>(cln::realpart(value)));
-       else if (!x.imag().is_rational())
+       else if (!instanceof(imagpart(value), cln::cl_RA_ring))
                prec = cln::float_format(cln::the<cln::cl_F>(cln::imagpart(value)));
 
        // [Kol] (5.3)
-       if ((cln::realpart(value) < -0.5) || (n == 0)) {
+       if ((cln::realpart(value) < -0.5) || (n == 0) || ((cln::abs(value) <= 1) && (cln::abs(value) > 0.95))) {
 
                cln::cl_N result = cln::expt(cln::cl_I(-1),p) * cln::expt(cln::log(value),n)
                                   * cln::expt(cln::log(1-value),p) / cln::factorial(n) / cln::factorial(p);
@@ -1892,9 +1993,9 @@ numeric S_num(int n, int p, const numeric& x)
                        cln::cl_N res2;
                        for (int r=0; r<p; r++) {
                                res2 = res2 + cln::expt(cln::cl_I(-1),r) * cln::expt(cln::log(1-value),r)
-                                             * S_num(p-r,n-s,1-value).to_cl_N() / cln::factorial(r);
+                                             * S_num(p-r,n-s,1-value) / cln::factorial(r);
                        }
-                       result = result + cln::expt(cln::log(value),s) * (S_num(n-s,p,1).to_cl_N() - res2) / cln::factorial(s);
+                       result = result + cln::expt(cln::log(value),s) * (S_num(n-s,p,1) - res2) / cln::factorial(s);
                }
 
                return result;
@@ -1909,7 +2010,7 @@ numeric S_num(int n, int p, const numeric& x)
                        for (int r=0; r<=s; r++) {
                                result = result + cln::expt(cln::cl_I(-1),s) * cln::expt(cln::log(-value),r) * cln::factorial(n+s-r-1)
                                                  / cln::factorial(r) / cln::factorial(s-r) / cln::factorial(n-1)
-                                                 * S_num(n+s-r,p-s,cln::recip(value)).to_cl_N();
+                                                 * S_num(n+s-r,p-s,cln::recip(value));
                        }
                }
                result = result * cln::expt(cln::cl_I(-1),n);
@@ -1945,12 +2046,18 @@ numeric S_num(int n, int p, const numeric& x)
 static ex S_evalf(const ex& n, const ex& p, const ex& x)
 {
        if (n.info(info_flags::posint) && p.info(info_flags::posint)) {
+               const int n_ = ex_to<numeric>(n).to_int();
+               const int p_ = ex_to<numeric>(p).to_int();
                if (is_a<numeric>(x)) {
-                       return S_num(ex_to<numeric>(n).to_int(), ex_to<numeric>(p).to_int(), ex_to<numeric>(x));
+                       const cln::cl_N x_ = ex_to<numeric>(x).to_cl_N();
+                       const cln::cl_N result = S_num(n_, p_, x_);
+                       return numeric(result);
                } else {
                        ex x_val = x.evalf();
                        if (is_a<numeric>(x_val)) {
-                               return S_num(ex_to<numeric>(n).to_int(), ex_to<numeric>(p).to_int(), ex_to<numeric>(x_val));
+                               const cln::cl_N x_val_ = ex_to<numeric>(x_val).to_cl_N();
+                               const cln::cl_N result = S_num(n_, p_, x_val_);
+                               return numeric(result);
                        }
                }
        }
@@ -1975,7 +2082,11 @@ static ex S_eval(const ex& n, const ex& p, const ex& x)
                        return Li(n+1, x);
                }
                if (x.info(info_flags::numeric) && (!x.info(info_flags::crational))) {
-                       return S_num(ex_to<numeric>(n).to_int(), ex_to<numeric>(p).to_int(), ex_to<numeric>(x));
+                       int n_ = ex_to<numeric>(n).to_int();
+                       int p_ = ex_to<numeric>(p).to_int();
+                       const cln::cl_N x_ = ex_to<numeric>(x).to_cl_N();
+                       const cln::cl_N result = S_num(n_, p_, x_);
+                       return numeric(result);
                }
        }
        if (n.is_zero()) {
@@ -1988,9 +2099,48 @@ static ex S_eval(const ex& n, const ex& p, const ex& x)
 
 static ex S_series(const ex& n, const ex& p, const ex& x, const relational& rel, int order, unsigned options)
 {
-       epvector seq;
-       seq.push_back(expair(S(n, p, x), 0));
-       return pseries(rel, seq);
+       if (p == _ex1) {
+               return Li(n+1, x).series(rel, order, options);
+       }
+
+       const ex x_pt = x.subs(rel, subs_options::no_pattern);
+       if (n.info(info_flags::posint) && p.info(info_flags::posint) && x_pt.info(info_flags::numeric)) {
+               // First special case: x==0 (derivatives have poles)
+               if (x_pt.is_zero()) {
+                       const symbol s;
+                       ex ser;
+                       // manually construct the primitive expansion
+                       // subsum = Euler-Zagier-Sum is needed
+                       // dirty hack (slow ...) calculation of subsum:
+                       std::vector<ex> presubsum, subsum;
+                       subsum.push_back(0);
+                       for (int i=1; i<order-1; ++i) {
+                               subsum.push_back(subsum[i-1] + numeric(1, i));
+                       }
+                       for (int depth=2; depth<p; ++depth) {
+                               presubsum = subsum;
+                               for (int i=1; i<order-1; ++i) {
+                                       subsum[i] = subsum[i-1] + numeric(1, i) * presubsum[i-1];
+                               }
+                       }
+                               
+                       for (int i=1; i<order; ++i) {
+                               ser += pow(s,i) / pow(numeric(i), n+1) * subsum[i-1];
+                       }
+                       // substitute the argument's series expansion
+                       ser = ser.subs(s==x.series(rel, order), subs_options::no_pattern);
+                       // maybe that was terminating, so add a proper order term
+                       epvector nseq;
+                       nseq.push_back(expair(Order(_ex1), order));
+                       ser += pseries(rel, nseq);
+                       // reexpanding it will collapse the series again
+                       return ser.series(rel, order);
+               }
+               // TODO special cases: x==1 (branch point) and x real, >=1 (branch cut)
+               throw std::runtime_error("S_series: don't know how to do the series expansion at this point!");
+       }
+       // all other cases should be safe, by now:
+       throw do_taylor();  // caught by function::series()
 }
 
 
@@ -2414,6 +2564,37 @@ ex trafo_H_1tx_prepend_zero(const ex& e, const ex& arg)
 }
 
 
+// do integration [ReV] (49)
+// put parameter 1 in front of existing parameters
+ex trafo_H_prepend_one(const ex& e, const ex& arg)
+{
+       ex h;
+       std::string name;
+       if (is_a<function>(e)) {
+               name = ex_to<function>(e).get_name();
+       }
+       if (name == "H") {
+               h = e;
+       } else {
+               for (int i=0; i<e.nops(); i++) {
+                       if (is_a<function>(e.op(i))) {
+                               std::string name = ex_to<function>(e.op(i)).get_name();
+                               if (name == "H") {
+                                       h = e.op(i);
+                               }
+                       }
+               }
+       }
+       if (h != 0) {
+               lst newparameter = ex_to<lst>(h.op(0));
+               newparameter.prepend(1);
+               return e.subs(h == H(newparameter, h.op(1)).hold());
+       } else {
+               return e * H(lst(1),1-arg).hold();
+       }
+}
+
+
 // do integration [ReV] (55)
 // put parameter -1 in front of existing parameters
 ex trafo_H_1tx_prepend_minusone(const ex& e, const ex& arg)
@@ -2509,6 +2690,107 @@ ex trafo_H_1mxt1px_prepend_one(const ex& e, const ex& arg)
 }
 
 
+// do x -> 1-x transformation
+struct map_trafo_H_1mx : public map_function
+{
+       ex operator()(const ex& e)
+       {
+               if (is_a<add>(e) || is_a<mul>(e)) {
+                       return e.map(*this);
+               }
+               
+               if (is_a<function>(e)) {
+                       std::string name = ex_to<function>(e).get_name();
+                       if (name == "H") {
+
+                               lst parameter = ex_to<lst>(e.op(0));
+                               ex arg = e.op(1);
+
+                               // special cases if all parameters are either 0, 1 or -1
+                               bool allthesame = true;
+                               if (parameter.op(0) == 0) {
+                                       for (int i=1; i<parameter.nops(); i++) {
+                                               if (parameter.op(i) != 0) {
+                                                       allthesame = false;
+                                                       break;
+                                               }
+                                       }
+                                       if (allthesame) {
+                                               lst newparameter;
+                                               for (int i=parameter.nops(); i>0; i--) {
+                                                       newparameter.append(1);
+                                               }
+                                               return pow(-1, parameter.nops()) * H(newparameter, 1-arg).hold();
+                                       }
+                               } else if (parameter.op(0) == -1) {
+                                       throw std::runtime_error("map_trafo_H_1mx: cannot handle weights equal -1!");
+                               } else {
+                                       for (int i=1; i<parameter.nops(); i++) {
+                                               if (parameter.op(i) != 1) {
+                                                       allthesame = false;
+                                                       break;
+                                               }
+                                       }
+                                       if (allthesame) {
+                                               lst newparameter;
+                                               for (int i=parameter.nops(); i>0; i--) {
+                                                       newparameter.append(0);
+                                               }
+                                               return pow(-1, parameter.nops()) * H(newparameter, 1-arg).hold();
+                                       }
+                               }
+
+                               lst newparameter = parameter;
+                               newparameter.remove_first();
+
+                               if (parameter.op(0) == 0) {
+
+                                       // leading zero
+                                       ex res = convert_H_to_zeta(parameter);
+                                       //ex res = convert_from_RV(parameter, 1).subs(H(wild(1),wild(2))==zeta(wild(1)));
+                                       map_trafo_H_1mx recursion;
+                                       ex buffer = recursion(H(newparameter, arg).hold());
+                                       if (is_a<add>(buffer)) {
+                                               for (int i=0; i<buffer.nops(); i++) {
+                                                       res -= trafo_H_prepend_one(buffer.op(i), arg);
+                                               }
+                                       } else {
+                                               res -= trafo_H_prepend_one(buffer, arg);
+                                       }
+                                       return res;
+
+                               } else {
+
+                                       // leading one
+                                       map_trafo_H_1mx recursion;
+                                       map_trafo_H_mult unify;
+                                       ex res = H(lst(1), arg).hold() * H(newparameter, arg).hold();
+                                       int firstzero = 0;
+                                       while (parameter.op(firstzero) == 1) {
+                                               firstzero++;
+                                       }
+                                       for (int i=firstzero-1; i<parameter.nops()-1; i++) {
+                                               lst newparameter;
+                                               int j=0;
+                                               for (; j<=i; j++) {
+                                                       newparameter.append(parameter[j+1]);
+                                               }
+                                               newparameter.append(1);
+                                               for (; j<parameter.nops()-1; j++) {
+                                                       newparameter.append(parameter[j+1]);
+                                               }
+                                               res -= H(newparameter, arg).hold();
+                                       }
+                                       res = recursion(res).expand() / firstzero;
+                                       return unify(res);
+                               }
+                       }
+               }
+               return e;
+       }
+};
+
+
 // do x -> 1/x transformation
 struct map_trafo_H_1overx : public map_function
 {
@@ -2822,6 +3104,7 @@ static ex H_evalf(const ex& x1, const ex& x2)
                        return filter(H(x1, xtemp).hold()).subs(xtemp==x2).evalf();
                }
                // ... and expand parameter notation
+               bool has_minus_one = false;
                lst m;
                for (lst::const_iterator it = morg.begin(); it != morg.end(); it++) {
                        if (*it > 1) {
@@ -2829,19 +3112,18 @@ static ex H_evalf(const ex& x1, const ex& x2)
                                        m.append(0);
                                }
                                m.append(1);
-                       } else if (*it < -1) {
+                       } else if (*it <= -1) {
                                for (ex count=*it+1; count < 0; count++) {
                                        m.append(0);
                                }
                                m.append(-1);
+                               has_minus_one = true;
                        } else {
                                m.append(*it);
                        }
                }
 
-               // since the transformations produce a lot of terms, they are only efficient for
-               // argument near one.
-               // no transformation needed -> do summation
+               // do summation
                if (cln::abs(x) < 0.95) {
                        lst m_lst;
                        lst s_lst;
@@ -2871,6 +3153,7 @@ static ex H_evalf(const ex& x1, const ex& x2)
                        }
                }
 
+               symbol xtemp("xtemp");
                ex res = 1;     
                
                // ensure that the realpart of the argument is positive
@@ -2884,14 +3167,8 @@ static ex H_evalf(const ex& x1, const ex& x2)
                        }
                }
 
-               // choose transformations
-               symbol xtemp("xtemp");
-               if (cln::abs(x-1) < 1.4142) {
-                       // x -> (1-x)/(1+x)
-                       map_trafo_H_1mxt1px trafo;
-                       res *= trafo(H(m, xtemp));
-               } else {
-                       // x -> 1/x
+               // x -> 1/x
+               if (cln::abs(x) >= 2.0) {
                        map_trafo_H_1overx trafo;
                        res *= trafo(H(m, xtemp));
                        if (cln::imagpart(x) <= 0) {
@@ -2899,17 +3176,25 @@ static ex H_evalf(const ex& x1, const ex& x2)
                        } else {
                                res = res.subs(H_polesign == I*Pi);
                        }
+                       return res.subs(xtemp == numeric(x)).evalf();
+               }
+               
+               // check transformations for 0.95 <= |x| < 2.0
+               
+               // |(1-x)/(1+x)| < 0.9 -> circular area with center=9.53+0i and radius=9.47
+               if (cln::abs(x-9.53) <= 9.47) {
+                       // x -> (1-x)/(1+x)
+                       map_trafo_H_1mxt1px trafo;
+                       res *= trafo(H(m, xtemp));
+               } else {
+                       // x -> 1-x
+                       if (has_minus_one) {
+                               map_trafo_H_convert_to_Li filter;
+                               return filter(H(m, numeric(x)).hold()).evalf();
+                       }
+                       map_trafo_H_1mx trafo;
+                       res *= trafo(H(m, xtemp));
                }
-
-               // simplify result
-// TODO
-//             map_trafo_H_convert converter;
-//             res = converter(res).expand();
-//             lst ll;
-//             res.find(H(wild(1),wild(2)), ll);
-//             res.find(zeta(wild(1)), ll);
-//             res.find(zeta(wild(1),wild(2)), ll);
-//             res = res.collect(ll);
 
                return res.subs(xtemp == numeric(x)).evalf();
        }
@@ -3132,13 +3417,6 @@ namespace {
 
 // parameters and data for [Cra] algorithm
 const cln::cl_N lambda = cln::cl_N("319/320");
-int L1;
-int L2;
-std::vector<std::vector<cln::cl_N> > f_kj;
-std::vector<cln::cl_N> crB;
-std::vector<std::vector<cln::cl_N> > crG;
-std::vector<cln::cl_N> crX;
-
 
 void halfcyclic_convolute(const std::vector<cln::cl_N>& a, const std::vector<cln::cl_N>& b, std::vector<cln::cl_N>& c)
 {
@@ -3153,44 +3431,39 @@ void halfcyclic_convolute(const std::vector<cln::cl_N>& a, const std::vector<cln
 
 
 // [Cra] section 4
-void initcX(const std::vector<int>& s)
+static void initcX(std::vector<cln::cl_N>& crX,
+                  const std::vector<int>& s,
+                  const int L2)
 {
-       const int k = s.size();
-
-       crX.clear();
-       crG.clear();
-       crB.clear();
-
-       for (int i=0; i<=L2; i++) {
-               crB.push_back(bernoulli(i).to_cl_N() / cln::factorial(i));
-       }
+       std::vector<cln::cl_N> crB(L2 + 1);
+       for (int i=0; i<=L2; i++)
+               crB[i] = bernoulli(i).to_cl_N() / cln::factorial(i);
 
        int Sm = 0;
        int Smp1 = 0;
-       for (int m=0; m<k-1; m++) {
-               std::vector<cln::cl_N> crGbuf;
-               Sm = Sm + s[m];
+       std::vector<std::vector<cln::cl_N> > crG(s.size() - 1, std::vector<cln::cl_N>(L2 + 1));
+       for (int m=0; m < s.size() - 1; m++) {
+               Sm += s[m];
                Smp1 = Sm + s[m+1];
-               for (int i=0; i<=L2; i++) {
-                       crGbuf.push_back(cln::factorial(i + Sm - m - 2) / cln::factorial(i + Smp1 - m - 2));
-               }
-               crG.push_back(crGbuf);
+               for (int i = 0; i <= L2; i++)
+                       crG[m][i] = cln::factorial(i + Sm - m - 2) / cln::factorial(i + Smp1 - m - 2);
        }
 
        crX = crB;
 
-       for (int m=0; m<k-1; m++) {
-               std::vector<cln::cl_N> Xbuf;
-               for (int i=0; i<=L2; i++) {
-                       Xbuf.push_back(crX[i] * crG[m][i]);
-               }
+       for (std::size_t m = 0; m < s.size() - 1; m++) {
+               std::vector<cln::cl_N> Xbuf(L2 + 1);
+               for (int i = 0; i <= L2; i++)
+                       Xbuf[i] = crX[i] * crG[m][i];
+
                halfcyclic_convolute(Xbuf, crB, crX);
        }
 }
 
 
 // [Cra] section 4
-cln::cl_N crandall_Y_loop(const cln::cl_N& Sqk)
+static cln::cl_N crandall_Y_loop(const cln::cl_N& Sqk,
+                                const std::vector<cln::cl_N>& crX)
 {
        cln::cl_F one = cln::cl_float(1, cln::float_format(Digits));
        cln::cl_N factor = cln::expt(lambda, Sqk);
@@ -3208,11 +3481,9 @@ cln::cl_N crandall_Y_loop(const cln::cl_N& Sqk)
 
 
 // [Cra] section 4
-void calc_f(int maxr)
+static void calc_f(std::vector<std::vector<cln::cl_N> >& f_kj,
+                  const int maxr, const int L1)
 {
-       f_kj.clear();
-       f_kj.resize(L1);
-       
        cln::cl_N t0, t1, t2, t3, t4;
        int i, j, k;
        std::vector<std::vector<cln::cl_N> >::iterator it = f_kj.begin();
@@ -3238,7 +3509,8 @@ void calc_f(int maxr)
 
 
 // [Cra] (3.1)
-cln::cl_N crandall_Z(const std::vector<int>& s)
+static cln::cl_N crandall_Z(const std::vector<int>& s,
+                           const std::vector<std::vector<cln::cl_N> >& f_kj)
 {
        const int j = s.size();
 
@@ -3279,6 +3551,8 @@ cln::cl_N zeta_do_sum_Crandall(const std::vector<int>& s)
        std::vector<int> r = s;
        const int j = r.size();
 
+       std::size_t L1;
+
        // decide on maximal size of f_kj for crandall_Z
        if (Digits < 50) {
                L1 = 150;
@@ -3286,6 +3560,7 @@ cln::cl_N zeta_do_sum_Crandall(const std::vector<int>& s)
                L1 = Digits * 3 + j*2;
        }
 
+       std::size_t L2;
        // decide on maximal size of crX for crandall_Y
        if (Digits < 38) {
                L2 = 63;
@@ -3312,7 +3587,8 @@ cln::cl_N zeta_do_sum_Crandall(const std::vector<int>& s)
                }
        }
 
-       calc_f(maxr);
+       std::vector<std::vector<cln::cl_N> > f_kj(L1);
+       calc_f(f_kj, maxr, L1);
 
        const cln::cl_N r0factorial = cln::factorial(r[0]-1);
 
@@ -3326,12 +3602,13 @@ cln::cl_N zeta_do_sum_Crandall(const std::vector<int>& s)
                Srun -= skp1buf;
                r.pop_back();
 
-               initcX(r);
+               std::vector<cln::cl_N> crX;
+               initcX(crX, r, L2);
                
                for (int q=0; q<skp1buf; q++) {
                        
-                       cln::cl_N pp1 = crandall_Y_loop(Srun+q-k);
-                       cln::cl_N pp2 = crandall_Z(rz);
+                       cln::cl_N pp1 = crandall_Y_loop(Srun+q-k, crX);
+                       cln::cl_N pp2 = crandall_Z(rz, f_kj);
 
                        rz.front()--;
                        
@@ -3345,9 +3622,11 @@ cln::cl_N zeta_do_sum_Crandall(const std::vector<int>& s)
        }
        rz.insert(rz.begin(), r.back());
 
-       initcX(rz);
+       std::vector<cln::cl_N> crX;
+       initcX(crX, rz, L2);
 
-       res = (res + crandall_Y_loop(S-j)) / r0factorial + crandall_Z(rz);
+       res = (res + crandall_Y_loop(S-j, crX)) / r0factorial
+               + crandall_Z(rz, f_kj);
 
        return res;
 }
@@ -3537,18 +3816,18 @@ static ex zeta1_eval(const ex& m)
                        if (y.is_zero()) {
                                return _ex_1_2;
                        }
-                       if (y.is_equal(_num1)) {
+                       if (y.is_equal(*_num1_p)) {
                                return zeta(m).hold();
                        }
                        if (y.info(info_flags::posint)) {
                                if (y.info(info_flags::odd)) {
                                        return zeta(m).hold();
                                } else {
-                                       return abs(bernoulli(y)) * pow(Pi, y) * pow(_num2, y-_num1) / factorial(y);
+                                       return abs(bernoulli(y)) * pow(Pi, y) * pow(*_num2_p, y-(*_num1_p)) / factorial(y);
                                }
                        } else {
                                if (y.info(info_flags::odd)) {
-                                       return -bernoulli(_num1-y) / (_num1-y);
+                                       return -bernoulli((*_num1_p)-y) / ((*_num1_p)-y);
                                } else {
                                        return _ex0;
                                }