Univariate Hensel lifting now uses upoly.

[ginac.git] / ginac / power.cpp

diff --git a/ginac/power.cpp b/ginac/power.cpp
index ec339b9a660afc6aac21fa9307b6bec5e26144ce..cbe63248afa6812b346f8c78c1c265cac73e8234 100644 (file)
--- a/ginac/power.cpp
+++ b/ginac/power.cpp
@@ -59,7 +59,7 @@ typedef std::vector<int> intvector;
 // default constructor
 //////////
 
-power::power() : inherited(&power::tinfo_static) { }
+power::power() { }
 
 //////////
 // other constructors
@@ -71,8 +71,9 @@ power::power() : inherited(&power::tinfo_static) { }
 // archiving
 //////////
 
-power::power(const archive_node &n, lst &sym_lst) : inherited(n, sym_lst)
+void power::read_archive(const archive_node &n, lst &sym_lst)
 {
+       inherited::read_archive(n, sym_lst);
        n.find_ex("basis", basis, sym_lst);
        n.find_ex("exponent", exponent, sym_lst);
 }
@@ -84,8 +85,6 @@ void power::archive(archive_node &n) const
        n.add_ex("exponent", exponent);
 }
 
-DEFAULT_UNARCHIVE(power)
-
 //////////
 // functions overriding virtual functions from base classes
 //////////
@@ -635,7 +634,7 @@ bool power::has(const ex & other, unsigned options) const
 }
 
 // from mul.cpp
-extern bool tryfactsubs(const ex &, const ex &, int &, lst &);
+extern bool tryfactsubs(const ex &, const ex &, int &, exmap&);
 
 ex power::subs(const exmap & m, unsigned options) const
 {      
@@ -651,9 +650,13 @@ ex power::subs(const exmap & m, unsigned options) const
 
        for (exmap::const_iterator it = m.begin(); it != m.end(); ++it) {
                int nummatches = std::numeric_limits<int>::max();
-               lst repls;
-               if (tryfactsubs(*this, it->first, nummatches, repls))
-                       return (ex_to<basic>((*this) * power(it->second.subs(ex(repls), subs_options::no_pattern) / it->first.subs(ex(repls), subs_options::no_pattern), nummatches))).subs_one_level(m, options);
+               exmap repls;
+               if (tryfactsubs(*this, it->first, nummatches, repls)) {
+                       ex anum = it->second.subs(repls, subs_options::no_pattern);
+                       ex aden = it->first.subs(repls, subs_options::no_pattern);
+                       ex result = (*this)*power(anum/aden, nummatches);
+                       return (ex_to<basic>(result)).subs_one_level(m, options);
+               }
        }
 
        return subs_one_level(m, options);
@@ -765,7 +768,7 @@ unsigned power::return_type() const
        return basis.return_type();
 }
 
-tinfo_t power::return_type_tinfo() const
+return_type_t power::return_type_tinfo() const
 {
        return basis.return_type_tinfo();
 }
@@ -864,7 +867,6 @@ ex power::expand_add(const add & a, int n, unsigned options) const
        intvector k(m-1);
        intvector k_cum(m-1); // k_cum[l]:=sum(i=0,l,k[l]);
        intvector upper_limit(m-1);
-       int l;
 
        for (size_t l=0; l<m-1; ++l) {
                k[l] = 0;
@@ -875,7 +877,7 @@ ex power::expand_add(const add & a, int n, unsigned options) const
        while (true) {
                exvector term;
                term.reserve(m+1);
-               for (l=0; l<m-1; ++l) {
+               for (std::size_t l = 0; l < m - 1; ++l) {
                        const ex & b = a.op(l);
                        GINAC_ASSERT(!is_exactly_a<add>(b));
                        GINAC_ASSERT(!is_exactly_a<power>(b) ||
@@ -890,7 +892,7 @@ ex power::expand_add(const add & a, int n, unsigned options) const
                                term.push_back(power(b,k[l]));
                }
 
-               const ex & b = a.op(l);
+               const ex & b = a.op(m - 1);
                GINAC_ASSERT(!is_exactly_a<add>(b));
                GINAC_ASSERT(!is_exactly_a<power>(b) ||
                             !is_exactly_a<numeric>(ex_to<power>(b).exponent) ||
@@ -904,7 +906,7 @@ ex power::expand_add(const add & a, int n, unsigned options) const
                        term.push_back(power(b,n-k_cum[m-2]));
 
                numeric f = binomial(numeric(n),numeric(k[0]));
-               for (l=1; l<m-1; ++l)
+               for (std::size_t l = 1; l < m - 1; ++l)
                        f *= binomial(numeric(n-k_cum[l-1]),numeric(k[l]));
 
                term.push_back(f);
@@ -912,12 +914,19 @@ ex power::expand_add(const add & a, int n, unsigned options) const
                result.push_back(ex((new mul(term))->setflag(status_flags::dynallocated)).expand(options));
 
                // increment k[]
-               l = m-2;
-               while ((l>=0) && ((++k[l])>upper_limit[l])) {
+               bool done = false;
+               std::size_t l = m - 2;
+               while ((++k[l]) > upper_limit[l]) {
                        k[l] = 0;
-                       --l;
+                       if (l != 0)
+                               --l;
+                       else {
+                               done = true;
+                               break;
+                       }
                }
-               if (l<0) break;
+               if (done)
+                       break;
 
                // recalc k_cum[] and upper_limit[]
                k_cum[l] = (l==0 ? k[0] : k_cum[l-1]+k[l]);
@@ -1051,4 +1060,6 @@ ex power::expand_mul(const mul & m, const numeric & n, unsigned options, bool fr
        return result;
 }
 
+GINAC_BIND_UNARCHIVER(power);
+
 } // namespace GiNaC