]> www.ginac.de Git - ginac.git/blobdiff - ginac/pseries.cpp
- added historical note.
[ginac.git] / ginac / pseries.cpp
index fbb7583b3bc1b0b10e7c16eacff1b86f5049fc24..398ca82c13c24e0ec02c6e458d09abb4ba47aebd 100644 (file)
 
 #include "pseries.h"
 #include "add.h"
-#include "inifcns.h"
+#include "inifcns.h" // for Order function
 #include "lst.h"
 #include "mul.h"
 #include "power.h"
 #include "relational.h"
 #include "symbol.h"
+#include "print.h"
 #include "archive.h"
 #include "utils.h"
 #include "debugmsg.h"
@@ -39,6 +40,7 @@ namespace GiNaC {
 
 GINAC_IMPLEMENT_REGISTERED_CLASS(pseries, basic)
 
+
 /*
  *  Default ctor, dtor, copy ctor, assignment operator and helpers
  */
@@ -56,11 +58,7 @@ void pseries::copy(const pseries &other)
        point = other.point;
 }
 
-void pseries::destroy(bool call_parent)
-{
-       if (call_parent)
-               inherited::destroy(call_parent);
-}
+DEFAULT_DESTROY(pseries)
 
 
 /*
@@ -90,7 +88,6 @@ pseries::pseries(const ex &rel_, const epvector &ops_) : basic(TINFO_pseries), s
  *  Archiving
  */
 
-/** Construct object from archive_node. */
 pseries::pseries(const archive_node &n, const lst &sym_lst) : inherited(n, sym_lst)
 {
        debugmsg("pseries ctor from archive_node", LOGLEVEL_CONSTRUCT);
@@ -106,13 +103,6 @@ pseries::pseries(const archive_node &n, const lst &sym_lst) : inherited(n, sym_l
        n.find_ex("point", point, sym_lst);
 }
 
-/** Unarchive the object. */
-ex pseries::unarchive(const archive_node &n, const lst &sym_lst)
-{
-       return (new pseries(n, sym_lst))->setflag(status_flags::dynallocated);
-}
-
-/** Archive the object. */
 void pseries::archive(archive_node &n) const
 {
        inherited::archive(n);
@@ -126,101 +116,126 @@ void pseries::archive(archive_node &n) const
        n.add_ex("point", point);
 }
 
+DEFAULT_UNARCHIVE(pseries)
+
 //////////
-// functions overriding virtual functions from bases classes
+// functions overriding virtual functions from base classes
 //////////
 
-void pseries::print(std::ostream &os, unsigned upper_precedence) const
+void pseries::print(const print_context & c, unsigned level) const
 {
        debugmsg("pseries print", LOGLEVEL_PRINT);
-       if (precedence<=upper_precedence) os << "(";
-       // objects of type pseries must not have any zero entries, so the
-       // trivial (zero) pseries needs a special treatment here:
-       if (seq.size()==0)
-               os << '0';
-       for (epvector::const_iterator i=seq.begin(); i!=seq.end(); ++i) {
-               // print a sign, if needed
-               if (i!=seq.begin())
-                       os << '+';
-               if (!is_order_function(i->rest)) {
-                       // print 'rest', i.e. the expansion coefficient
-                       if (i->rest.info(info_flags::numeric) &&
-                               i->rest.info(info_flags::positive)) {
-                               os << i->rest;
-                       } else
-                               os << "(" << i->rest << ')';
-                       // print 'coeff', something like (x-1)^42
-                       if (!i->coeff.is_zero()) {
-                               os << '*';
-                               if (!point.is_zero())
-                                       os << '(' << var-point << ')';
-                               else
-                                       os << var;
-                               if (i->coeff.compare(_ex1())) {
-                                       os << '^';
-                                       if (i->coeff.info(info_flags::negative))
-                                               os << '(' << i->coeff << ')';
-                                       else
-                                               os << i->coeff;
-                               }
-                       }
-               } else {
-                       os << Order(power(var-point,i->coeff));
-               }
-       }
-       if (precedence<=upper_precedence) os << ")";
-}
 
+       if (is_a<print_tree>(c)) {
+
+               c.s << std::string(level, ' ') << class_name()
+                   << std::hex << ", hash=0x" << hashvalue << ", flags=0x" << flags << std::dec
+                   << std::endl;
+               unsigned delta_indent = static_cast<const print_tree &>(c).delta_indent;
+               unsigned num = seq.size();
+               for (unsigned i=0; i<num; ++i) {
+                       seq[i].rest.print(c, level + delta_indent);
+                       seq[i].coeff.print(c, level + delta_indent);
+                       c.s << std::string(level + delta_indent, ' ') << "-----" << std::endl;
+               }
+               var.print(c, level + delta_indent);
+               point.print(c, level + delta_indent);
 
-void pseries::printraw(std::ostream &os) const
-{
-       debugmsg("pseries printraw", LOGLEVEL_PRINT);
-       os << "pseries(" << var << ";" << point << ";";
-       for (epvector::const_iterator i=seq.begin(); i!=seq.end(); ++i)
-               os << "(" << (*i).rest << "," << (*i).coeff << "),";
-       os << ")";
-}
+       } else {
 
+               if (precedence() <= level)
+                       c.s << "(";
+               
+               std::string par_open = is_a<print_latex>(c) ? "{(" : "(";
+               std::string par_close = is_a<print_latex>(c) ? ")}" : ")";
+               
+               // objects of type pseries must not have any zero entries, so the
+               // trivial (zero) pseries needs a special treatment here:
+               if (seq.empty())
+                       c.s << '0';
+               epvector::const_iterator i = seq.begin(), end = seq.end();
+               while (i != end) {
+                       // print a sign, if needed
+                       if (i != seq.begin())
+                               c.s << '+';
+                       if (!is_order_function(i->rest)) {
+                               // print 'rest', i.e. the expansion coefficient
+                               if (i->rest.info(info_flags::numeric) &&
+                                       i->rest.info(info_flags::positive)) {
+                                       i->rest.print(c);
+                               } else {
+                                       c.s << par_open;
+                                       i->rest.print(c);
+                                       c.s << par_close;
+                               }
+                               // print 'coeff', something like (x-1)^42
+                               if (!i->coeff.is_zero()) {
+                                       if (is_a<print_latex>(c))
+                                               c.s << ' ';
+                                       else
+                                               c.s << '*';
+                                       if (!point.is_zero()) {
+                                               c.s << par_open;
+                                               (var-point).print(c);
+                                               c.s << par_close;
+                                       } else
+                                               var.print(c);
+                                       if (i->coeff.compare(_ex1())) {
+                                               c.s << '^';
+                                               if (i->coeff.info(info_flags::negative)) {
+                                                       c.s << par_open;
+                                                       i->coeff.print(c);
+                                                       c.s << par_close;
+                                               } else {
+                                                       if (is_a<print_latex>(c)) {
+                                                               c.s << '{';
+                                                               i->coeff.print(c);
+                                                               c.s << '}';
+                                                       } else
+                                                               i->coeff.print(c);
+                                               }
+                                       }
+                               }
+                       } else
+                               Order(power(var-point,i->coeff)).print(c);
+                       ++i;
+               }
 
-void pseries::printtree(std::ostream & os, unsigned indent) const
-{
-       debugmsg("pseries printtree",LOGLEVEL_PRINT);
-       os << std::string(indent,' ') << "pseries " 
-          << ", hash=" << hashvalue
-          << " (0x" << std::hex << hashvalue << std::dec << ")"
-          << ", flags=" << flags << std::endl;
-       for (unsigned i=0; i<seq.size(); ++i) {
-               seq[i].rest.printtree(os,indent+delta_indent);
-               seq[i].coeff.printtree(os,indent+delta_indent);
-               if (i!=seq.size()-1)
-                       os << std::string(indent+delta_indent,' ') << "-----" << std::endl;
+               if (precedence() <= level)
+                       c.s << ")";
        }
-       var.printtree(os, indent+delta_indent);
-       point.printtree(os, indent+delta_indent);
 }
 
 int pseries::compare_same_type(const basic & other) const
 {
        GINAC_ASSERT(is_of_type(other, pseries));
        const pseries &o = static_cast<const pseries &>(other);
-
+       
+       // first compare the lengths of the series...
+       if (seq.size()>o.seq.size())
+               return 1;
+       if (seq.size()<o.seq.size())
+               return -1;
+       
+       // ...then the expansion point...
        int cmpval = var.compare(o.var);
        if (cmpval)
                return cmpval;
        cmpval = point.compare(o.point);
        if (cmpval)
                return cmpval;
-
-       epvector::const_iterator it1 = seq.begin(), it2 = o.seq.begin(), it1end = seq.end(), it2end = o.seq.end();
-       while ((it1 != it1end) && (it2 != it2end)) {
-               cmpval = it1->compare(*it2);
+       
+       // ...and if that failed the individual elements
+       epvector::const_iterator it = seq.begin(), o_it = o.seq.begin();
+       while (it!=seq.end() && o_it!=o.seq.end()) {
+               cmpval = it->compare(*o_it);
                if (cmpval)
                        return cmpval;
-               it1++; it2++;
+               ++it;
+               ++o_it;
        }
-       if (it1 == it1end)
-               return it2 == it2end ? 0 : -1;
 
+       // so they are equal.
        return 0;
 }
 
@@ -230,7 +245,6 @@ unsigned pseries::nops(void) const
        return seq.size();
 }
 
-
 /** Return the ith term in the series when represented as a sum. */
 ex pseries::op(int i) const
 {
@@ -239,22 +253,20 @@ ex pseries::op(int i) const
        return seq[i].rest * power(var - point, seq[i].coeff);
 }
 
-
 ex &pseries::let_op(int i)
 {
        throw (std::logic_error("let_op not defined for pseries"));
 }
 
-
 /** Return degree of highest power of the series.  This is usually the exponent
  *  of the Order term.  If s is not the expansion variable of the series, the
  *  series is examined termwise. */
-int pseries::degree(const symbol &s) const
+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();
+                       return ex_to<numeric>((*(seq.end() - 1)).coeff).to_int();
                else
                        return 0;
        } else {
@@ -277,12 +289,12 @@ int pseries::degree(const symbol &s) const
  *  series is examined termwise.  If s is the expansion variable but the
  *  expansion point is not zero the series is not expanded to find the degree.
  *  I.e.: (1-x) + (1-x)^2 + Order((1-x)^3) has ldegree(x) 1, not 0. */
-int pseries::ldegree(const symbol &s) const
+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();
+                       return ex_to<numeric>((*(seq.begin())).coeff).to_int();
                else
                        return 0;
        } else {
@@ -307,10 +319,10 @@ int pseries::ldegree(const symbol &s) const
  *  If s is not the expansion variable, an attempt is made to convert the
  *  series to a polynomial and return the corresponding coefficient from
  *  there. */
-ex pseries::coeff(const symbol &s, int n) const
+ex pseries::coeff(const ex &s, int n) const
 {
        if (var.is_equal(s)) {
-               if (seq.size() == 0)
+               if (seq.empty())
                        return _ex0();
                
                // Binary search in sequence for given power
@@ -319,7 +331,7 @@ ex pseries::coeff(const symbol &s, int n) const
                while (lo <= hi) {
                        int mid = (lo + hi) / 2;
                        GINAC_ASSERT(is_ex_exactly_of_type(seq[mid].coeff, numeric));
-                       int cmp = ex_to_numeric(seq[mid].coeff).compare(looking_for);
+                       int cmp = ex_to<numeric>(seq[mid].coeff).compare(looking_for);
                        switch (cmp) {
                                case -1:
                                        lo = mid + 1;
@@ -339,12 +351,11 @@ ex pseries::coeff(const symbol &s, int n) const
 }
 
 /** Does nothing. */
-ex pseries::collect(const symbol &s) const
+ex pseries::collect(const ex &s, bool distributed) const
 {
        return *this;
 }
 
-
 /** Evaluate coefficients. */
 ex pseries::eval(int level) const
 {
@@ -365,7 +376,6 @@ ex pseries::eval(int level) const
        return (new pseries(relational(var,point), new_seq))->setflag(status_flags::dynallocated | status_flags::evaluated);
 }
 
-
 /** Evaluate coefficients numerically. */
 ex pseries::evalf(int level) const
 {
@@ -386,14 +396,13 @@ ex pseries::evalf(int level) const
        return (new pseries(relational(var,point), new_seq))->setflag(status_flags::dynallocated | status_flags::evaluated);
 }
 
-
-ex pseries::subs(const lst & ls, const lst & lr) const
+ex pseries::subs(const lst & ls, const lst & lr, bool no_pattern) const
 {
        // If expansion variable is being substituted, convert the series to a
        // polynomial and do the substitution there because the result might
        // no longer be a power series
        if (ls.has(var))
-               return convert_to_poly(true).subs(ls, lr);
+               return convert_to_poly(true).subs(ls, lr, no_pattern);
        
        // Otherwise construct a new series with substituted coefficients and
        // expansion point
@@ -401,28 +410,28 @@ ex pseries::subs(const lst & ls, const lst & lr) const
        newseq.reserve(seq.size());
        epvector::const_iterator it = seq.begin(), itend = seq.end();
        while (it != itend) {
-               newseq.push_back(expair(it->rest.subs(ls, lr), it->coeff));
+               newseq.push_back(expair(it->rest.subs(ls, lr, no_pattern), it->coeff));
                ++it;
        }
-       return (new pseries(relational(var,point.subs(ls, lr)), newseq))->setflag(status_flags::dynallocated);
+       return (new pseries(relational(var,point.subs(ls, lr, no_pattern)), newseq))->setflag(status_flags::dynallocated);
 }
 
-
 /** Implementation of ex::expand() for a power series.  It expands all the
  *  terms individually and returns the resulting series as a new pseries. */
 ex pseries::expand(unsigned options) const
 {
        epvector newseq;
-       for (epvector::const_iterator i=seq.begin(); i!=seq.end(); ++i) {
+       epvector::const_iterator i = seq.begin(), end = seq.end();
+       while (i != end) {
                ex restexp = i->rest.expand();
                if (!restexp.is_zero())
                        newseq.push_back(expair(restexp, i->coeff));
+               ++i;
        }
        return (new pseries(relational(var,point), newseq))
-               ->setflag(status_flags::dynallocated | status_flags::expanded);
+               ->setflag(status_flags::dynallocated | (options == 0 ? status_flags::expanded : 0));
 }
 
-
 /** Implementation of ex::diff() for a power series.  It treats the series as a
  *  polynomial.
  *  @see ex::diff */
@@ -449,10 +458,6 @@ ex pseries::derivative(const symbol & s) const
        }
 }
 
-
-/** Convert a pseries object to an ordinary polynomial.
- *
- *  @param no_order flag: discard higher order terms */
 ex pseries::convert_to_poly(bool no_order) const
 {
        ex e;
@@ -469,12 +474,9 @@ ex pseries::convert_to_poly(bool no_order) const
        return e;
 }
 
-
-/** Returns true if there is no order term, i.e. the series terminates and
- *  false otherwise. */
 bool pseries::is_terminating(void) const
 {
-       return seq.size() == 0 || !is_order_function((seq.end()-1)->rest);
+       return seq.empty() || !is_order_function((seq.end()-1)->rest);
 }
 
 
@@ -490,15 +492,15 @@ ex basic::series(const relational & r, int order, unsigned options) const
        numeric fac(1);
        ex deriv = *this;
        ex coeff = deriv.subs(r);
-       const symbol *s = static_cast<symbol *>(r.lhs().bp);
+       const symbol &s = static_cast<symbol &>(*r.lhs().bp);
        
        if (!coeff.is_zero())
-               seq.push_back(expair(coeff, numeric(0)));
+               seq.push_back(expair(coeff, _ex0()));
        
        int n;
        for (n=1; n<order; ++n) {
                fac = fac.mul(numeric(n));
-               deriv = deriv.diff(*s).expand();
+               deriv = deriv.diff(s).expand();
                if (deriv.is_zero()) {
                        // Series terminates
                        return pseries(r, seq);
@@ -509,7 +511,7 @@ ex basic::series(const relational & r, int order, unsigned options) const
        }
        
        // Higher-order terms, if present
-       deriv = deriv.diff(*s);
+       deriv = deriv.diff(s);
        if (!deriv.expand().is_zero())
                seq.push_back(expair(Order(_ex1()), numeric(n)));
        return pseries(r, seq);
@@ -523,9 +525,9 @@ ex symbol::series(const relational & r, int order, unsigned options) const
        epvector seq;
        const ex point = r.rhs();
        GINAC_ASSERT(is_ex_exactly_of_type(r.lhs(),symbol));
-       const symbol *s = static_cast<symbol *>(r.lhs().bp);
+       ex s = r.lhs();
        
-       if (this->is_equal(*s)) {
+       if (this->is_equal(*s.bp)) {
                if (order > 0 && !point.is_zero())
                        seq.push_back(expair(point, _ex0()));
                if (order > 1)
@@ -569,7 +571,7 @@ ex pseries::add_series(const pseries &other) const
                        }
                        break;
                } else
-                       pow_a = ex_to_numeric((*a).coeff).to_int();
+                       pow_a = ex_to<numeric>((*a).coeff).to_int();
                
                // If b is empty, fill up with elements from a and stop
                if (b == b_end) {
@@ -579,7 +581,7 @@ ex pseries::add_series(const pseries &other) const
                        }
                        break;
                } else
-                       pow_b = ex_to_numeric((*b).coeff).to_int();
+                       pow_b = ex_to<numeric>((*b).coeff).to_int();
                
                // a and b are non-empty, compare powers
                if (pow_a < pow_b) {
@@ -632,10 +634,10 @@ ex add::series(const relational & r, int order, unsigned options) const
                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 = ex_to<pseries>(op).mul_const(ex_to<numeric>(it->coeff));
                
                // Series addition
-               acc = ex_to_pseries(acc).add_series(ex_to_pseries(op));
+               acc = ex_to<pseries>(acc).add_series(ex_to<pseries>(op));
        }
        return acc;
 }
@@ -681,19 +683,18 @@ ex pseries::mul_series(const pseries &other) const
        // Series multiplication
        epvector new_seq;
        
-       const symbol *s = static_cast<symbol *>(var.bp);
-       int a_max = degree(*s);
-       int b_max = other.degree(*s);
-       int a_min = ldegree(*s);
-       int b_min = other.ldegree(*s);
+       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;
        int cdeg_max = a_max + b_max;
        
        int higher_order_a = INT_MAX;
        int higher_order_b = INT_MAX;
-       if (is_order_function(coeff(*s, a_max)))
+       if (is_order_function(coeff(var, a_max)))
                higher_order_a = a_max + b_min;
-       if (is_order_function(other.coeff(*s, b_max)))
+       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);
        if (cdeg_max >= higher_order_c)
@@ -703,8 +704,8 @@ ex pseries::mul_series(const pseries &other) const
                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(*s, i);
-                       ex b_coeff = other.coeff(*s, cdeg-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;
                }
@@ -713,7 +714,7 @@ ex pseries::mul_series(const pseries &other) const
        }
        if (higher_order_c < 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), new_seq);
 }
 
 
@@ -735,15 +736,15 @@ ex mul::series(const relational & r, int order, unsigned options) const
                if (op.info(info_flags::numeric)) {
                        // series * const (special case, faster)
                        ex f = power(op, it->coeff);
-                       acc = ex_to_pseries(acc).mul_const(ex_to_numeric(f));
+                       acc = ex_to<pseries>(acc).mul_const(ex_to<numeric>(f));
                        continue;
                } else if (!is_ex_exactly_of_type(op, pseries))
                        op = op.series(r, order, options);
                if (!it->coeff.is_equal(_ex1()))
-                       op = ex_to_pseries(op).power_const(ex_to_numeric(it->coeff), order);
+                       op = ex_to<pseries>(op).power_const(ex_to<numeric>(it->coeff), order);
 
                // Series multiplication
-               acc = ex_to_pseries(acc).mul_series(ex_to_pseries(op));
+               acc = ex_to<pseries>(acc).mul_series(ex_to<pseries>(op));
        }
        return acc;
 }
@@ -756,6 +757,7 @@ ex mul::series(const relational & r, int order, unsigned options) const
 ex pseries::power_const(const numeric &p, int deg) const
 {
        // method:
+       // (due to Leonhard Euler)
        // let A(x) be this series and for the time being let it start with a
        // constant (later we'll generalize):
        //     A(x) = a_0 + a_1*x + a_2*x^2 + ...
@@ -775,7 +777,7 @@ ex pseries::power_const(const numeric &p, int deg) const
        // repeat the above derivation.  The leading power of C2(x) = A2(x)^2 is
        // then of course x^(p*m) but the recurrence formula still holds.
        
-       if (seq.size()==0) {
+       if (seq.empty()) {
                // as a spacial case, handle the empty (zero) series honoring the
                // usual power laws such as implemented in power::eval()
                if (p.real().is_zero())
@@ -786,18 +788,17 @@ ex pseries::power_const(const numeric &p, int deg) const
                        return *this;
        }
        
-       const symbol *s = static_cast<symbol *>(var.bp);
-       int ldeg = ldegree(*s);
+       int ldeg = ldegree(var);
        
        // Compute coefficients of the powered series
        exvector co;
        co.reserve(deg);
-       co.push_back(power(coeff(*s, ldeg), p));
+       co.push_back(power(coeff(var, ldeg), p));
        bool all_sums_zero = true;
        for (int i=1; i<deg; ++i) {
                ex sum = _ex0();
                for (int j=1; j<=i; ++j) {
-                       ex c = coeff(*s, j + ldeg);
+                       ex c = coeff(var, j + ldeg);
                        if (is_order_function(c)) {
                                co.push_back(Order(_ex1()));
                                break;
@@ -806,7 +807,7 @@ ex pseries::power_const(const numeric &p, int deg) const
                }
                if (!sum.is_zero())
                        all_sums_zero = false;
-               co.push_back(sum / coeff(*s, ldeg) / numeric(i));
+               co.push_back(sum / coeff(var, ldeg) / numeric(i));
        }
        
        // Construct new series (of non-zero coefficients)
@@ -829,9 +830,12 @@ ex pseries::power_const(const numeric &p, int deg) const
 /** Return a new pseries object with the powers shifted by deg. */
 pseries pseries::shift_exponents(int deg) const
 {
-       epvector newseq(seq);
-       for (epvector::iterator i=newseq.begin(); i!=newseq.end(); ++i)
-               i->coeff = i->coeff + deg;
+       epvector newseq = seq;
+       epvector::iterator i = newseq.begin(), end  = newseq.end();
+       while (i != end) {
+               i->coeff += deg;
+               ++i;
+       }
        return pseries(relational(var, point), newseq);
 }
 
@@ -867,7 +871,7 @@ ex power::series(const relational & r, int order, unsigned options) const
        }
        
        // Power e
-       return ex_to_pseries(e).power_const(ex_to_numeric(exponent), order);
+       return ex_to<pseries>(e).power_const(ex_to<numeric>(exponent), order);
 }
 
 
@@ -876,16 +880,16 @@ ex pseries::series(const relational & r, int order, unsigned options) const
 {
        const ex p = r.rhs();
        GINAC_ASSERT(is_ex_exactly_of_type(r.lhs(),symbol));
-       const symbol *s = static_cast<symbol *>(r.lhs().bp);
+       const symbol &s = static_cast<symbol &>(*r.lhs().bp);
        
-       if (var.is_equal(*s) && point.is_equal(p)) {
-               if (order > degree(*s))
+       if (var.is_equal(s) && point.is_equal(p)) {
+               if (order > degree(s))
                        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();
+                               int o = ex_to<numeric>(it->coeff).to_int();
                                if (o >= order) {
                                        new_seq.push_back(expair(Order(_ex1()), o));
                                        break;
@@ -916,7 +920,7 @@ ex ex::series(const ex & r, int order, unsigned options) const
        relational rel_;
        
        if (is_ex_exactly_of_type(r,relational))
-               rel_ = ex_to_relational(r);
+               rel_ = ex_to<relational>(r);
        else if (is_ex_exactly_of_type(r,symbol))
                rel_ = relational(r,_ex0());
        else
@@ -930,12 +934,4 @@ ex ex::series(const ex & r, int order, unsigned options) const
        return e;
 }
 
-//////////
-// static member variables
-//////////
-
-// protected
-
-unsigned pseries::precedence = 38;  // for clarity just below add::precedence
-
 } // namespace GiNaC