]> www.ginac.de Git - ginac.git/blobdiff - ginac/pseries.cpp
Remove 'level' argument of evalf().
[ginac.git] / ginac / pseries.cpp
index 99eed8a20cbdbe896571e46cad519f303c97ff83..2ea4365f57324d868b6e956e9e6d940b92c52fa6 100644 (file)
@@ -4,7 +4,7 @@
  *  methods for series expansion. */
 
 /*
- *  GiNaC Copyright (C) 1999-2015 Johannes Gutenberg University Mainz, Germany
+ *  GiNaC Copyright (C) 1999-2016 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
@@ -68,8 +68,43 @@ pseries::pseries() { }
  *  @param rel_  expansion variable and point (must hold a relational)
  *  @param ops_  vector of {coefficient, power} pairs (coefficient must not be zero)
  *  @return newly constructed pseries */
-pseries::pseries(const ex &rel_, const epvector &ops_) : seq(ops_)
+pseries::pseries(const ex &rel_, const epvector &ops_)
+  : seq(ops_)
 {
+#ifdef DO_GINAC_ASSERT
+       auto i = seq.begin();
+       while (i != seq.end()) {
+               auto ip1 = i+1;
+               if (ip1 != seq.end())
+                       GINAC_ASSERT(!is_order_function(i->rest));
+               else
+                       break;
+               GINAC_ASSERT(is_a<numeric>(i->coeff));
+               GINAC_ASSERT(ex_to<numeric>(i->coeff) < ex_to<numeric>(ip1->coeff));
+               ++i;
+       }
+#endif // def DO_GINAC_ASSERT
+       GINAC_ASSERT(is_a<relational>(rel_));
+       GINAC_ASSERT(is_a<symbol>(rel_.lhs()));
+       point = rel_.rhs();
+       var = rel_.lhs();
+}
+pseries::pseries(const ex &rel_, epvector &&ops_)
+  : seq(std::move(ops_))
+{
+#ifdef DO_GINAC_ASSERT
+       auto i = seq.begin();
+       while (i != seq.end()) {
+               auto ip1 = i+1;
+               if (ip1 != seq.end())
+                       GINAC_ASSERT(!is_order_function(i->rest));
+               else
+                       break;
+               GINAC_ASSERT(is_a<numeric>(i->coeff));
+               GINAC_ASSERT(ex_to<numeric>(i->coeff) < ex_to<numeric>(ip1->coeff));
+               ++i;
+       }
+#endif // def DO_GINAC_ASSERT
        GINAC_ASSERT(is_a<relational>(rel_));
        GINAC_ASSERT(is_a<symbol>(rel_.lhs()));
        point = rel_.rhs();
@@ -84,12 +119,12 @@ pseries::pseries(const ex &rel_, const epvector &ops_) : seq(ops_)
 void pseries::read_archive(const archive_node &n, lst &sym_lst) 
 {
        inherited::read_archive(n, sym_lst);
-       archive_node::archive_node_cit first = n.find_first("coeff");
-       archive_node::archive_node_cit last = n.find_last("power");
+       auto first = n.find_first("coeff");
+       auto last = n.find_last("power");
        ++last;
        seq.reserve((last-first)/2);
 
-       for (archive_node::archive_node_cit loc = first; loc < last;) {
+       for (auto loc = first; loc < last;) {
                ex rest;
                ex coeff;
                n.find_ex_by_loc(loc++, rest, sym_lst);
@@ -104,11 +139,9 @@ void pseries::read_archive(const archive_node &n, lst &sym_lst)
 void pseries::archive(archive_node &n) const
 {
        inherited::archive(n);
-       epvector::const_iterator i = seq.begin(), iend = seq.end();
-       while (i != iend) {
-               n.add_ex("coeff", i->rest);
-               n.add_ex("power", i->coeff);
-               ++i;
+       for (auto & it : seq) {
+               n.add_ex("coeff", it.rest);
+               n.add_ex("power", it.coeff);
        }
        n.add_ex("var", var);
        n.add_ex("point", point);
@@ -129,7 +162,7 @@ void pseries::print_series(const print_context & c, const char *openbrace, const
        if (seq.empty())
                c.s << '0';
 
-       epvector::const_iterator i = seq.begin(), end = seq.end();
+       auto i = seq.begin(), end = seq.end();
        while (i != end) {
 
                // print a sign, if needed
@@ -170,7 +203,7 @@ void pseries::print_series(const print_context & c, const char *openbrace, const
                                }
                        }
                } else
-                       Order(power(var-point,i->coeff)).print(c);
+                       Order(pow(var - point, i->coeff)).print(c);
                ++i;
        }
 
@@ -274,8 +307,8 @@ ex pseries::op(size_t i) const
                throw (std::out_of_range("op() out of range"));
 
        if (is_order_function(seq[i].rest))
-               return Order(power(var-point, seq[i].coeff));
-       return seq[i].rest * power(var - point, seq[i].coeff);
+               return Order(pow(var-point, seq[i].coeff));
+       return seq[i].rest * pow(var - point, seq[i].coeff);
 }
 
 /** Return degree of highest power of the series.  This is usually the exponent
@@ -283,25 +316,17 @@ ex pseries::op(size_t i) const
  *  series is examined termwise. */
 int pseries::degree(const ex &s) const
 {
-       if (var.is_equal(s)) {
-               // Return last exponent
-               if (seq.size())
-                       return ex_to<numeric>((seq.end()-1)->coeff).to_int();
-               else
-                       return 0;
-       } else {
-               epvector::const_iterator it = seq.begin(), itend = seq.end();
-               if (it == itend)
-                       return 0;
-               int max_pow = std::numeric_limits<int>::min();
-               while (it != itend) {
-                       int pow = it->rest.degree(s);
-                       if (pow > max_pow)
-                               max_pow = pow;
-                       ++it;
-               }
-               return max_pow;
-       }
+       if (seq.empty())
+               return 0;
+
+       if (var.is_equal(s))
+               // Return last/greatest exponent
+               return ex_to<numeric>((seq.end()-1)->coeff).to_int();
+
+       int max_pow = std::numeric_limits<int>::min();
+       for (auto & it : seq)
+               max_pow = std::max(max_pow, it.rest.degree(s));
+       return max_pow;
 }
 
 /** Return degree of lowest power of the series.  This is usually the exponent
@@ -311,25 +336,17 @@ int pseries::degree(const ex &s) const
  *  I.e.: (1-x) + (1-x)^2 + Order((1-x)^3) has ldegree(x) 1, not 0. */
 int pseries::ldegree(const ex &s) const
 {
-       if (var.is_equal(s)) {
-               // Return first exponent
-               if (seq.size())
-                       return ex_to<numeric>((seq.begin())->coeff).to_int();
-               else
-                       return 0;
-       } else {
-               epvector::const_iterator it = seq.begin(), itend = seq.end();
-               if (it == itend)
-                       return 0;
-               int min_pow = std::numeric_limits<int>::max();
-               while (it != itend) {
-                       int pow = it->rest.ldegree(s);
-                       if (pow < min_pow)
-                               min_pow = pow;
-                       ++it;
-               }
-               return min_pow;
-       }
+       if (seq.empty())
+               return 0;
+
+       if (var.is_equal(s))
+               // Return first/smallest exponent
+               return ex_to<numeric>((seq.begin())->coeff).to_int();
+
+       int min_pow = std::numeric_limits<int>::max();
+       for (auto & it : seq)
+               min_pow = std::min(min_pow, it.rest.degree(s));
+       return min_pow;
 }
 
 /** Return coefficient of degree n in power series if s is the expansion
@@ -377,43 +394,31 @@ ex pseries::collect(const ex &s, bool distributed) const
 }
 
 /** Perform coefficient-wise automatic term rewriting rules in this class. */
-ex pseries::eval(int level) const
+ex pseries::eval() const
 {
-       if (level == 1)
-               return this->hold();
-       
-       if (level == -max_recursion_level)
-               throw (std::runtime_error("pseries::eval(): recursion limit exceeded"));
-       
+       if (flags & status_flags::evaluated) {
+               return *this;
+       }
+
        // Construct a new series with evaluated coefficients
        epvector new_seq;
        new_seq.reserve(seq.size());
-       epvector::const_iterator it = seq.begin(), itend = seq.end();
-       while (it != itend) {
-               new_seq.push_back(expair(it->rest.eval(level-1), it->coeff));
-               ++it;
-       }
-       return (new pseries(relational(var,point), new_seq))->setflag(status_flags::dynallocated | status_flags::evaluated);
+       for (auto & it : seq)
+               new_seq.push_back(expair(it.rest, it.coeff));
+
+       return dynallocate<pseries>(relational(var,point), std::move(new_seq)).setflag(status_flags::evaluated);
 }
 
 /** Evaluate coefficients numerically. */
-ex pseries::evalf(int level) const
+ex pseries::evalf() const
 {
-       if (level == 1)
-               return *this;
-       
-       if (level == -max_recursion_level)
-               throw (std::runtime_error("pseries::evalf(): recursion limit exceeded"));
-       
        // Construct a new series with evaluated coefficients
        epvector new_seq;
        new_seq.reserve(seq.size());
-       epvector::const_iterator it = seq.begin(), itend = seq.end();
-       while (it != itend) {
-               new_seq.push_back(expair(it->rest.evalf(level-1), it->coeff));
-               ++it;
-       }
-       return (new pseries(relational(var,point), new_seq))->setflag(status_flags::dynallocated | status_flags::evaluated);
+       for (auto & it : seq)
+               new_seq.push_back(expair(it.rest, it.coeff));
+
+       return dynallocate<pseries>(relational(var,point), std::move(new_seq)).setflag(status_flags::evaluated);
 }
 
 ex pseries::conjugate() const
@@ -421,16 +426,14 @@ ex pseries::conjugate() const
        if(!var.info(info_flags::real))
                return conjugate_function(*this).hold();
 
-       epvector * newseq = conjugateepvector(seq);
+       std::unique_ptr<epvector> newseq(conjugateepvector(seq));
        ex newpoint = point.conjugate();
 
        if (!newseq && are_ex_trivially_equal(point, newpoint)) {
                return *this;
        }
 
-       ex result = (new pseries(var==newpoint, newseq ? *newseq : seq))->setflag(status_flags::dynallocated);
-       delete newseq;
-       return result;
+       return dynallocate<pseries>(var==newpoint, newseq ? std::move(*newseq) : seq);
 }
 
 ex pseries::real_part() const
@@ -443,9 +446,9 @@ ex pseries::real_part() const
 
        epvector v;
        v.reserve(seq.size());
-       for(epvector::const_iterator i=seq.begin(); i!=seq.end(); ++i)
-               v.push_back(expair((i->rest).real_part(), i->coeff));
-       return (new pseries(var==point, v))->setflag(status_flags::dynallocated);
+       for (auto & it : seq)
+               v.push_back(expair((it.rest).real_part(), it.coeff));
+       return dynallocate<pseries>(var==point, std::move(v));
 }
 
 ex pseries::imag_part() const
@@ -458,24 +461,24 @@ ex pseries::imag_part() const
 
        epvector v;
        v.reserve(seq.size());
-       for(epvector::const_iterator i=seq.begin(); i!=seq.end(); ++i)
-               v.push_back(expair((i->rest).imag_part(), i->coeff));
-       return (new pseries(var==point, v))->setflag(status_flags::dynallocated);
+       for (auto & it : seq)
+               v.push_back(expair((it.rest).imag_part(), it.coeff));
+       return dynallocate<pseries>(var==point, std::move(v));
 }
 
 ex pseries::eval_integ() const
 {
-       epvector *newseq = NULL;
-       for (epvector::const_iterator i=seq.begin(); i!=seq.end(); ++i) {
+       std::unique_ptr<epvector> newseq(nullptr);
+       for (auto i=seq.begin(); i!=seq.end(); ++i) {
                if (newseq) {
                        newseq->push_back(expair(i->rest.eval_integ(), i->coeff));
                        continue;
                }
                ex newterm = i->rest.eval_integ();
                if (!are_ex_trivially_equal(newterm, i->rest)) {
-                       newseq = new epvector;
+                       newseq.reset(new epvector);
                        newseq->reserve(seq.size());
-                       for (epvector::const_iterator j=seq.begin(); j!=i; ++j)
+                       for (auto j=seq.begin(); j!=i; ++j)
                                newseq->push_back(*j);
                        newseq->push_back(expair(newterm, i->coeff));
                }
@@ -483,8 +486,7 @@ ex pseries::eval_integ() const
 
        ex newpoint = point.eval_integ();
        if (newseq || !are_ex_trivially_equal(newpoint, point))
-               return (new pseries(var==newpoint, *newseq))
-                      ->setflag(status_flags::dynallocated);
+               return dynallocate<pseries>(var==newpoint, std::move(*newseq));
        return *this;
 }
 
@@ -493,13 +495,12 @@ ex pseries::evalm() const
        // evalm each coefficient
        epvector newseq;
        bool something_changed = false;
-       for (epvector::const_iterator i=seq.begin(); i!=seq.end(); ++i) {
+       for (auto i=seq.begin(); i!=seq.end(); ++i) {
                if (something_changed) {
                        ex newcoeff = i->rest.evalm();
                        if (!newcoeff.is_zero())
                                newseq.push_back(expair(newcoeff, i->coeff));
-               }
-               else {
+               } else {
                        ex newcoeff = i->rest.evalm();
                        if (!are_ex_trivially_equal(newcoeff, i->rest)) {
                                something_changed = true;
@@ -511,7 +512,7 @@ ex pseries::evalm() const
                }
        }
        if (something_changed)
-               return (new pseries(var==point, newseq))->setflag(status_flags::dynallocated);
+               return dynallocate<pseries>(var==point, std::move(newseq));
        else
                return *this;
 }
@@ -528,12 +529,9 @@ ex pseries::subs(const exmap & m, unsigned options) const
        // expansion point
        epvector newseq;
        newseq.reserve(seq.size());
-       epvector::const_iterator it = seq.begin(), itend = seq.end();
-       while (it != itend) {
-               newseq.push_back(expair(it->rest.subs(m, options), it->coeff));
-               ++it;
-       }
-       return (new pseries(relational(var,point.subs(m, options)), newseq))->setflag(status_flags::dynallocated);
+       for (auto & it : seq)
+               newseq.push_back(expair(it.rest.subs(m, options), it.coeff));
+       return dynallocate<pseries>(relational(var,point.subs(m, options)), std::move(newseq));
 }
 
 /** Implementation of ex::expand() for a power series.  It expands all the
@@ -541,15 +539,12 @@ ex pseries::subs(const exmap & m, unsigned options) const
 ex pseries::expand(unsigned options) const
 {
        epvector newseq;
-       epvector::const_iterator i = seq.begin(), end = seq.end();
-       while (i != end) {
-               ex restexp = i->rest.expand();
+       for (auto & it : seq) {
+               ex restexp = it.rest.expand();
                if (!restexp.is_zero())
-                       newseq.push_back(expair(restexp, i->coeff));
-               ++i;
+                       newseq.push_back(expair(restexp, it.coeff));
        }
-       return (new pseries(relational(var,point), newseq))
-               ->setflag(status_flags::dynallocated | (options == 0 ? status_flags::expanded : 0));
+       return dynallocate<pseries>(relational(var,point), std::move(newseq)).setflag(options == 0 ? status_flags::expanded : 0);
 }
 
 /** Implementation of ex::diff() for a power series.
@@ -557,51 +552,45 @@ ex pseries::expand(unsigned options) const
 ex pseries::derivative(const symbol & s) const
 {
        epvector new_seq;
-       epvector::const_iterator it = seq.begin(), itend = seq.end();
 
        if (s == var) {
                
                // FIXME: coeff might depend on var
-               while (it != itend) {
-                       if (is_order_function(it->rest)) {
-                               new_seq.push_back(expair(it->rest, it->coeff - 1));
+               for (auto & it : seq) {
+                       if (is_order_function(it.rest)) {
+                               new_seq.push_back(expair(it.rest, it.coeff - 1));
                        } else {
-                               ex c = it->rest * it->coeff;
+                               ex c = it.rest * it.coeff;
                                if (!c.is_zero())
-                                       new_seq.push_back(expair(c, it->coeff - 1));
+                                       new_seq.push_back(expair(c, it.coeff - 1));
                        }
-                       ++it;
                }
 
        } else {
 
-               while (it != itend) {
-                       if (is_order_function(it->rest)) {
-                               new_seq.push_back(*it);
+               for (auto & it : seq) {
+                       if (is_order_function(it.rest)) {
+                               new_seq.push_back(it);
                        } else {
-                               ex c = it->rest.diff(s);
+                               ex c = it.rest.diff(s);
                                if (!c.is_zero())
-                                       new_seq.push_back(expair(c, it->coeff));
+                                       new_seq.push_back(expair(c, it.coeff));
                        }
-                       ++it;
                }
        }
 
-       return pseries(relational(var,point), new_seq);
+       return pseries(relational(var,point), std::move(new_seq));
 }
 
 ex pseries::convert_to_poly(bool no_order) const
 {
        ex e;
-       epvector::const_iterator it = seq.begin(), itend = seq.end();
-       
-       while (it != itend) {
-               if (is_order_function(it->rest)) {
+       for (auto & it : seq) {
+               if (is_order_function(it.rest)) {
                        if (!no_order)
-                               e += Order(power(var - point, it->coeff));
+                               e += Order(pow(var - point, it.coeff));
                } else
-                       e += it->rest * power(var - point, it->coeff);
-               ++it;
+                       e += it.rest * pow(var - point, it.coeff);
        }
        return e;
 }
@@ -613,7 +602,7 @@ bool pseries::is_terminating() const
 
 ex pseries::coeffop(size_t i) const
 {
-       if (i >=nops())
+       if (i >= nops())
                throw (std::out_of_range("coeffop() out of range"));
        return seq[i].rest;
 }
@@ -640,7 +629,7 @@ ex basic::series(const relational & r, int order, unsigned options) const
        // default for order-values that make no sense for Taylor expansion
        if ((order <= 0) && this->has(s)) {
                seq.push_back(expair(Order(_ex1), order));
-               return pseries(r, seq);
+               return pseries(r, std::move(seq));
        }
 
        // do Taylor expansion
@@ -654,24 +643,24 @@ ex basic::series(const relational & r, int order, unsigned options) const
 
        int n;
        for (n=1; n<order; ++n) {
-               fac = fac.mul(n);
+               fac = fac.div(n);
                // We need to test for zero in order to see if the series terminates.
                // The problem is that there is no such thing as a perfect test for
                // zero.  Expanding the term occasionally helps a little...
                deriv = deriv.diff(s).expand();
                if (deriv.is_zero())  // Series terminates
-                       return pseries(r, seq);
+                       return pseries(r, std::move(seq));
 
                coeff = deriv.subs(r, subs_options::no_pattern);
                if (!coeff.is_zero())
-                       seq.push_back(expair(fac.inverse() * coeff, n));
+                       seq.push_back(expair(fac * coeff, n));
        }
        
        // Higher-order terms, if present
        deriv = deriv.diff(s);
        if (!deriv.expand().is_zero())
                seq.push_back(expair(Order(_ex1), n));
-       return pseries(r, seq);
+       return pseries(r, std::move(seq));
 }
 
 
@@ -692,7 +681,7 @@ ex symbol::series(const relational & r, int order, unsigned options) const
                        seq.push_back(expair(Order(_ex1), numeric(order)));
        } else
                seq.push_back(expair(*this, _ex0));
-       return pseries(r, seq);
+       return pseries(r, std::move(seq));
 }
 
 
@@ -706,17 +695,14 @@ ex pseries::add_series(const pseries &other) const
        // Adding two series with different variables or expansion points
        // results in an empty (constant) series 
        if (!is_compatible_to(other)) {
-               epvector nul;
-               nul.push_back(expair(Order(_ex1), _ex0));
-               return pseries(relational(var,point), nul);
+               epvector nul { expair(Order(_ex1), _ex0) };
+               return pseries(relational(var,point), std::move(nul));
        }
        
        // Series addition
        epvector new_seq;
-       epvector::const_iterator a = seq.begin();
-       epvector::const_iterator b = other.seq.begin();
-       epvector::const_iterator a_end = seq.end();
-       epvector::const_iterator b_end = other.seq.end();
+       auto a = seq.begin(), a_end = seq.end();
+       auto b = other.seq.begin(), b_end = other.seq.end();
        int pow_a = std::numeric_limits<int>::max(), pow_b = std::numeric_limits<int>::max();
        for (;;) {
                // If a is empty, fill up with elements from b and stop
@@ -766,7 +752,7 @@ ex pseries::add_series(const pseries &other) const
                        }
                }
        }
-       return pseries(relational(var,point), new_seq);
+       return pseries(relational(var,point), std::move(new_seq));
 }
 
 
@@ -781,16 +767,14 @@ ex add::series(const relational & r, int order, unsigned options) const
        acc = overall_coeff.series(r, order, options);
        
        // Add remaining terms
-       epvector::const_iterator it = seq.begin();
-       epvector::const_iterator itend = seq.end();
-       for (; it!=itend; ++it) {
+       for (auto & it : seq) {
                ex op;
-               if (is_exactly_a<pseries>(it->rest))
-                       op = it->rest;
+               if (is_exactly_a<pseries>(it.rest))
+                       op = it.rest;
                else
-                       op = it->rest.series(r, order, options);
-               if (!it->coeff.is_equal(_ex1))
-                       op = ex_to<pseries>(op).mul_const(ex_to<numeric>(it->coeff));
+                       op = it.rest.series(r, order, options);
+               if (!it.coeff.is_equal(_ex1))
+                       op = ex_to<pseries>(op).mul_const(ex_to<numeric>(it.coeff));
                
                // Series addition
                acc = ex_to<pseries>(acc).add_series(ex_to<pseries>(op));
@@ -809,15 +793,13 @@ ex pseries::mul_const(const numeric &other) const
        epvector new_seq;
        new_seq.reserve(seq.size());
        
-       epvector::const_iterator it = seq.begin(), itend = seq.end();
-       while (it != itend) {
-               if (!is_order_function(it->rest))
-                       new_seq.push_back(expair(it->rest * other, it->coeff));
+       for (auto & it : seq) {
+               if (!is_order_function(it.rest))
+                       new_seq.push_back(expair(it.rest * other, it.coeff));
                else
-                       new_seq.push_back(*it);
-               ++it;
+                       new_seq.push_back(it);
        }
-       return pseries(relational(var,point), new_seq);
+       return pseries(relational(var,point), std::move(new_seq));
 }
 
 
@@ -831,23 +813,21 @@ ex pseries::mul_series(const pseries &other) const
        // Multiplying two series with different variables or expansion points
        // results in an empty (constant) series 
        if (!is_compatible_to(other)) {
-               epvector nul;
-               nul.push_back(expair(Order(_ex1), _ex0));
-               return pseries(relational(var,point), nul);
+               epvector nul { expair(Order(_ex1), _ex0) };
+               return pseries(relational(var,point), std::move(nul));
        }
 
        if (seq.empty() || other.seq.empty()) {
-               return (new pseries(var==point, epvector()))
-                      ->setflag(status_flags::dynallocated);
+               return dynallocate<pseries>(var==point, epvector());
        }
        
        // Series multiplication
        epvector new_seq;
-       int a_max = degree(var);
-       int b_max = other.degree(var);
-       int a_min = ldegree(var);
-       int b_min = other.ldegree(var);
-       int cdeg_min = a_min + b_min;
+       const int a_max = degree(var);
+       const int b_max = other.degree(var);
+       const int a_min = ldegree(var);
+       const int b_min = other.ldegree(var);
+       const int cdeg_min = a_min + b_min;
        int cdeg_max = a_max + b_max;
        
        int higher_order_a = std::numeric_limits<int>::max();
@@ -856,25 +836,37 @@ ex pseries::mul_series(const pseries &other) const
                higher_order_a = a_max + b_min;
        if (is_order_function(other.coeff(var, b_max)))
                higher_order_b = b_max + a_min;
-       int higher_order_c = std::min(higher_order_a, higher_order_b);
+       const int higher_order_c = std::min(higher_order_a, higher_order_b);
        if (cdeg_max >= higher_order_c)
                cdeg_max = higher_order_c - 1;
-       
+
+       std::map<int, ex> rest_map_a, rest_map_b;
+       for (const auto& it : seq)
+               rest_map_a[ex_to<numeric>(it.coeff).to_int()] = it.rest;
+
+       if (other.var.is_equal(var))
+               for (const auto& it : other.seq)
+                       rest_map_b[ex_to<numeric>(it.coeff).to_int()] = it.rest;
+
        for (int cdeg=cdeg_min; cdeg<=cdeg_max; ++cdeg) {
                ex co = _ex0;
                // c(i)=a(0)b(i)+...+a(i)b(0)
                for (int i=a_min; cdeg-i>=b_min; ++i) {
-                       ex a_coeff = coeff(var, i);
-                       ex b_coeff = other.coeff(var, cdeg-i);
-                       if (!is_order_function(a_coeff) && !is_order_function(b_coeff))
-                               co += a_coeff * b_coeff;
+                       const auto& ita = rest_map_a.find(i);
+                       if (ita == rest_map_a.end())
+                               continue;
+                       const auto& itb = rest_map_b.find(cdeg-i);
+                       if (itb == rest_map_b.end())
+                               continue;
+                       if (!is_order_function(ita->second) && !is_order_function(itb->second))
+                               co += ita->second * itb->second;
                }
                if (!co.is_zero())
                        new_seq.push_back(expair(co, numeric(cdeg)));
        }
        if (higher_order_c < std::numeric_limits<int>::max())
                new_seq.push_back(expair(Order(_ex1), numeric(higher_order_c)));
-       return pseries(relational(var, point), new_seq);
+       return pseries(relational(var, point), std::move(new_seq));
 }
 
 
@@ -893,20 +885,18 @@ ex mul::series(const relational & r, int order, unsigned options) const
        std::vector<bool> ldegree_redo;
 
        // find minimal degrees
-       const epvector::const_iterator itbeg = seq.begin();
-       const epvector::const_iterator itend = seq.end();
        // first round: obtain a bound up to which minimal degrees have to be
        // considered
-       for (epvector::const_iterator it=itbeg; it!=itend; ++it) {
+       for (auto & it : seq) {
 
-               ex expon = it->coeff;
+               ex expon = it.coeff;
                int factor = 1;
                ex buf;
                if (expon.info(info_flags::integer)) {
-                       buf = it->rest;
+                       buf = it.rest;
                        factor = ex_to<numeric>(expon).to_int();
                } else {
-                       buf = recombine_pair_to_ex(*it);
+                       buf = recombine_pair_to_ex(it);
                }
 
                int real_ldegree = 0;
@@ -943,16 +933,16 @@ ex mul::series(const relational & r, int order, unsigned options) const
        // method.
        // here we can ignore ldegrees larger than degbound
        size_t j = 0;
-       for (epvector::const_iterator it=itbeg; it!=itend; ++it) {
+       for (auto & it : seq) {
                if ( ldegree_redo[j] ) {
-                       ex expon = it->coeff;
+                       ex expon = it.coeff;
                        int factor = 1;
                        ex buf;
                        if (expon.info(info_flags::integer)) {
-                               buf = it->rest;
+                               buf = it.rest;
                                factor = ex_to<numeric>(expon).to_int();
                        } else {
-                               buf = recombine_pair_to_ex(*it);
+                               buf = recombine_pair_to_ex(it);
                        }
                        int real_ldegree = 0;
                        int orderloop = 0;
@@ -960,7 +950,7 @@ ex mul::series(const relational & r, int order, unsigned options) const
                                orderloop++;
                                real_ldegree = buf.series(r, orderloop, options).ldegree(sym);
                        } while ((real_ldegree == orderloop)
-                                       && ( factor*real_ldegree < degbound));
+                             && (factor*real_ldegree < degbound));
                        ldegrees[j] = factor * real_ldegree;
                        degbound -= factor * real_ldegree;
                }
@@ -970,20 +960,19 @@ ex mul::series(const relational & r, int order, unsigned options) const
        int degsum = std::accumulate(ldegrees.begin(), ldegrees.end(), 0);
 
        if (degsum >= order) {
-               epvector epv;
-               epv.push_back(expair(Order(_ex1), order));
-               return (new pseries(r, epv))->setflag(status_flags::dynallocated);
+               epvector epv { expair(Order(_ex1), order) };
+               return dynallocate<pseries>(r, std::move(epv));
        }
 
        // Multiply with remaining terms
-       std::vector<int>::const_iterator itd = ldegrees.begin();
-       for (epvector::const_iterator it=itbeg; it!=itend; ++it, ++itd) {
+       auto itd = ldegrees.begin();
+       for (auto it=seq.begin(), itend=seq.end(); it!=itend; ++it, ++itd) {
 
                // do series expansion with adjusted order
                ex op = recombine_pair_to_ex(*it).series(r, order-degsum+(*itd), options);
 
                // Series multiplication
-               if (it == itbeg)
+               if (it == seq.begin())
                        acc = ex_to<pseries>(op);
                else
                        acc = ex_to<pseries>(acc.mul_series(ex_to<pseries>(op)));
@@ -1038,11 +1027,8 @@ ex pseries::power_const(const numeric &p, int deg) const
        // adjust number of coefficients
        int numcoeff = deg - (p*ldeg).to_int();
        if (numcoeff <= 0) {
-               epvector epv;
-               epv.reserve(1);
-               epv.push_back(expair(Order(_ex1), deg));
-               return (new pseries(relational(var,point), epv))
-                      ->setflag(status_flags::dynallocated);
+               epvector epv { expair(Order(_ex1), deg) };
+               return dynallocate<pseries>(relational(var,point), std::move(epv));
        }
        
        // O(x^n)^(-m) is undefined
@@ -1052,7 +1038,7 @@ ex pseries::power_const(const numeric &p, int deg) const
        // Compute coefficients of the powered series
        exvector co;
        co.reserve(numcoeff);
-       co.push_back(power(coeff(var, ldeg), p));
+       co.push_back(pow(coeff(var, ldeg), p));
        for (int i=1; i<numcoeff; ++i) {
                ex sum = _ex0;
                for (int j=1; j<=i; ++j) {
@@ -1080,7 +1066,7 @@ ex pseries::power_const(const numeric &p, int deg) const
        if (!higher_order)
                new_seq.push_back(expair(Order(_ex1), p * ldeg + numcoeff));
 
-       return pseries(relational(var,point), new_seq);
+       return pseries(relational(var,point), std::move(new_seq));
 }
 
 
@@ -1088,12 +1074,9 @@ ex pseries::power_const(const numeric &p, int deg) const
 pseries pseries::shift_exponents(int deg) const
 {
        epvector newseq = seq;
-       epvector::iterator i = newseq.begin(), end  = newseq.end();
-       while (i != end) {
-               i->coeff += deg;
-               ++i;
-       }
-       return pseries(relational(var, point), newseq);
+       for (auto & it : newseq)
+               it.coeff += deg;
+       return pseries(relational(var, point), std::move(newseq));
 }
 
 
@@ -1154,7 +1137,7 @@ ex power::series(const relational & r, int order, unsigned options) const
                        new_seq.push_back(expair(_ex1, exponent));
                else
                        new_seq.push_back(expair(Order(_ex1), exponent));
-               return pseries(r, new_seq);
+               return pseries(r, std::move(new_seq));
        }
 
        // No, expand basis into series
@@ -1187,9 +1170,8 @@ ex power::series(const relational & r, int order, unsigned options) const
        try {
                result = ex_to<pseries>(e).power_const(numexp, order);
        } catch (pole_error) {
-               epvector ser;
-               ser.push_back(expair(Order(_ex1), order));
-               result = pseries(r, ser);
+               epvector ser { expair(Order(_ex1), order) };
+               result = pseries(r, std::move(ser));
        }
 
        return result;
@@ -1208,17 +1190,15 @@ ex pseries::series(const relational & r, int order, unsigned options) const
                        return *this;
                else {
                        epvector new_seq;
-                       epvector::const_iterator it = seq.begin(), itend = seq.end();
-                       while (it != itend) {
-                               int o = ex_to<numeric>(it->coeff).to_int();
+                       for (auto & it : seq) {
+                               int o = ex_to<numeric>(it.coeff).to_int();
                                if (o >= order) {
                                        new_seq.push_back(expair(Order(_ex1), o));
                                        break;
                                }
-                               new_seq.push_back(*it);
-                               ++it;
+                               new_seq.push_back(it);
                        }
-                       return pseries(r, new_seq);
+                       return pseries(r, std::move(new_seq));
                }
        } else
                return convert_to_poly().series(r, order, options);
@@ -1244,7 +1224,7 @@ ex integral::series(const relational & r, int order, unsigned options) const
        }
 
        // Expanding lower boundary
-       ex result = (new pseries(r, fexpansion))->setflag(status_flags::dynallocated);
+       ex result = dynallocate<pseries>(r, std::move(fexpansion));
        ex aseries = (a-a.subs(r)).series(r, order, options);
        fseries = f.series(x == (a.subs(r)), order, options);
        for (size_t i=0; i<fseries.nops(); ++i) {