]> www.ginac.de Git - ginac.git/blobdiff - ginac/pseries.cpp
cache pseries coeff accesses in pseries::mul_series.
[ginac.git] / ginac / pseries.cpp
index 2ae10f4f73a3150e9f6fcfc5373fd8afecc2fd29..8f267e8de4d49c0062d5d1ed910aea1c61f53cff 100644 (file)
@@ -68,7 +68,16 @@ 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_)
+{
+       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_))
 {
        GINAC_ASSERT(is_a<relational>(rel_));
        GINAC_ASSERT(is_a<symbol>(rel_.lhs()));
@@ -168,7 +177,7 @@ 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;
        }
 
@@ -272,8 +281,8 @@ 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
@@ -375,23 +384,21 @@ 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));
+               new_seq.push_back(expair(it->rest, it->coeff));
                ++it;
        }
-       return (new pseries(relational(var,point), std::move(new_seq)))->setflag(status_flags::dynallocated | status_flags::evaluated);
+       return dynallocate<pseries>(relational(var,point), std::move(new_seq)).setflag(status_flags::evaluated);
 }
 
 /** Evaluate coefficients numerically. */
@@ -411,7 +418,7 @@ ex pseries::evalf(int level) const
                new_seq.push_back(expair(it->rest.evalf(level-1), it->coeff));
                ++it;
        }
-       return (new pseries(relational(var,point), std::move(new_seq)))->setflag(status_flags::dynallocated | status_flags::evaluated);
+       return dynallocate<pseries>(relational(var,point), std::move(new_seq)).setflag(status_flags::evaluated);
 }
 
 ex pseries::conjugate() const
@@ -426,7 +433,7 @@ ex pseries::conjugate() const
                return *this;
        }
 
-       return (new pseries(var==newpoint, newseq ? std::move(*newseq) : seq))->setflag(status_flags::dynallocated);
+       return dynallocate<pseries>(var==newpoint, newseq ? std::move(*newseq) : seq);
 }
 
 ex pseries::real_part() const
@@ -441,7 +448,7 @@ ex pseries::real_part() const
        v.reserve(seq.size());
        for (auto & it : seq)
                v.push_back(expair((it.rest).real_part(), it.coeff));
-       return (new pseries(var==point, std::move(v)))->setflag(status_flags::dynallocated);
+       return dynallocate<pseries>(var==point, std::move(v));
 }
 
 ex pseries::imag_part() const
@@ -456,12 +463,12 @@ ex pseries::imag_part() const
        v.reserve(seq.size());
        for (auto & it : seq)
                v.push_back(expair((it.rest).imag_part(), it.coeff));
-       return (new pseries(var==point, std::move(v)))->setflag(status_flags::dynallocated);
+       return dynallocate<pseries>(var==point, std::move(v));
 }
 
 ex pseries::eval_integ() const
 {
-       epvector *newseq = nullptr;
+       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));
@@ -469,7 +476,7 @@ ex pseries::eval_integ() const
                }
                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 (auto j=seq.begin(); j!=i; ++j)
                                newseq->push_back(*j);
@@ -479,8 +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;
 }
 
@@ -494,8 +500,7 @@ ex pseries::evalm() const
                        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;
@@ -507,7 +512,7 @@ ex pseries::evalm() const
                }
        }
        if (something_changed)
-               return (new pseries(var==point, std::move(newseq)))->setflag(status_flags::dynallocated);
+               return dynallocate<pseries>(var==point, std::move(newseq));
        else
                return *this;
 }
@@ -526,7 +531,7 @@ ex pseries::subs(const exmap & m, unsigned options) const
        newseq.reserve(seq.size());
        for (auto & it : seq)
                newseq.push_back(expair(it.rest.subs(m, options), it.coeff));
-       return (new pseries(relational(var,point.subs(m, options)), newseq))->setflag(status_flags::dynallocated);
+       return dynallocate<pseries>(relational(var,point.subs(m, options)), std::move(newseq));
 }
 
 /** Implementation of ex::expand() for a power series.  It expands all the
@@ -539,8 +544,7 @@ ex pseries::expand(unsigned options) const
                if (!restexp.is_zero())
                        newseq.push_back(expair(restexp, it.coeff));
        }
-       return (new pseries(relational(var,point), std::move(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.
@@ -584,9 +588,9 @@ ex pseries::convert_to_poly(bool no_order) const
        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);
+                       e += it.rest * pow(var - point, it.coeff);
        }
        return e;
 }
@@ -625,7 +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
@@ -639,24 +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));
 }
 
 
@@ -677,7 +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));
 }
 
 
@@ -691,9 +695,8 @@ 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
@@ -796,7 +799,7 @@ ex pseries::mul_const(const numeric &other) const
                else
                        new_seq.push_back(it);
        }
-       return pseries(relational(var,point), new_seq);
+       return pseries(relational(var,point), std::move(new_seq));
 }
 
 
@@ -810,23 +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();
@@ -835,25 +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));
 }
 
 
@@ -947,9 +960,8 @@ 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
@@ -1015,11 +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
@@ -1029,7 +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) {
@@ -1057,7 +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));
 }
 
 
@@ -1128,7 +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
@@ -1161,9 +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;
@@ -1190,7 +1198,7 @@ ex pseries::series(const relational & r, int order, unsigned options) const
                                }
                                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);
@@ -1216,7 +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) {