]> www.ginac.de Git - ginac.git/blobdiff - ginac/expairseq.cpp
some more comments and cleanups to mul::expand() and ncmul::expand()
[ginac.git] / ginac / expairseq.cpp
index 605494ad3257dd6ab332b1075dd1f2a09dc204ab..f49fefcf208495ddf3a9d9d78f8a744bebf36092 100644 (file)
@@ -200,10 +200,11 @@ void expairseq::print(const print_context & c, unsigned level) const
                    << std::hex << ", hash=0x" << hashvalue << ", flags=0x" << flags << std::dec
                    << ", nops=" << nops()
                    << std::endl;
-               for (unsigned i=0; i<seq.size(); ++i) {
+               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);
-                       if (i != seq.size()-1)
+                       if (i != num - 1)
                                c.s << std::string(level + delta_indent, ' ') << "-----" << std::endl;
                }
                if (!overall_coeff.is_equal(default_overall_coeff())) {
@@ -233,7 +234,7 @@ void expairseq::print(const print_context & c, unsigned level) const
                                        c.s << *it-seq.begin() << " ";
                                        ++this_bin_fill;
                                }
-                               os << std::endl;
+                               c.s << std::endl;
                                cum_fill += this_bin_fill;
                                cum_fill_sq += this_bin_fill*this_bin_fill;
                        }
@@ -307,10 +308,13 @@ ex expairseq::map(map_function & f) const
        epvector::const_iterator cit = seq.begin(), last = seq.end();
        while (cit != last) {
                v->push_back(split_ex_to_pair(f(recombine_pair_to_ex(*cit))));
-               cit++;
+               ++cit;
        }
 
-       return thisexpairseq(v, f(overall_coeff));
+       if (overall_coeff.is_equal(default_overall_coeff()))
+               return thisexpairseq(v, default_overall_coeff());
+       else
+               return thisexpairseq(v, f(overall_coeff));
 }
 
 ex expairseq::eval(int level) const
@@ -365,7 +369,7 @@ bool expairseq::match(const ex & pattern, lst & repl_lst) const
                                        ops.erase(it);
                                        goto found;
                                }
-                               it++;
+                               ++it;
                        }
                        return false; // no match found
 found:         ;
@@ -376,9 +380,10 @@ found:             ;
                        // Assign all the remaining terms to the global wildcard (unless
                        // it has already been matched before, in which case the matches
                        // must be equal)
+                       unsigned num = ops.size();
                        epvector *vp = new epvector();
-                       vp->reserve(ops.size());
-                       for (unsigned i=0; i<ops.size(); i++)
+                       vp->reserve(num);
+                       for (unsigned i=0; i<num; i++)
                                vp->push_back(split_ex_to_pair(ops[i]));
                        ex rest = thisexpairseq(vp, default_overall_coeff());
                        for (unsigned i=0; i<repl_lst.nops(); i++) {
@@ -547,15 +552,17 @@ unsigned expairseq::return_type(void) const
 unsigned expairseq::calchash(void) const
 {
        unsigned v = golden_ratio_hash(tinfo());
-       for (epvector::const_iterator cit=seq.begin(); cit!=seq.end(); ++cit) {
+       epvector::const_iterator i = seq.begin(), end = seq.end();
+       while (i != end) {
 #if !EXPAIRSEQ_USE_HASHTAB
                v = rotate_left_31(v); // rotation would spoil commutativity
 #endif // EXPAIRSEQ_USE_HASHTAB
-               v ^= cit->rest.gethash();
+               v ^= i->rest.gethash();
 #if !EXPAIRSEQ_USE_HASHTAB
                v = rotate_left_31(v);
-               v ^= cit->coeff.gethash();
+               v ^= i->coeff.gethash();
 #endif // EXPAIRSEQ_USE_HASHTAB
+               ++i;
        }
        
        v ^= overall_coeff.gethash();
@@ -575,7 +582,7 @@ ex expairseq::expand(unsigned options) const
        epvector *vp = expandchildren(options);
        if (vp == NULL) {
                // The terms have not changed, so it is safe to declare this expanded
-               return this->setflag(status_flags::expanded);
+               return (options == 0) ? setflag(status_flags::expanded) : *this;
        } else
                return thisexpairseq(vp, overall_coeff);
 }
@@ -886,16 +893,15 @@ void expairseq::construct_from_expairseq_ex(const expairseq &s,
        
        // merge p into s.seq
        while (first!=last) {
-               int cmpval=(*first).rest.compare(p.rest);
+               int cmpval = (*first).rest.compare(p.rest);
                if (cmpval==0) {
                        // combine terms
-                       const numeric &newcoeff = ex_to<numeric>((*first).coeff).
+                       const numeric &newcoeff = ex_to<numeric>(first->coeff).
                                                   add(ex_to<numeric>(p.coeff));
                        if (!newcoeff.is_zero()) {
-                               seq.push_back(expair((*first).rest,newcoeff));
-                               if (expair_needs_further_processing(seq.end()-1)) {
+                               seq.push_back(expair(first->rest,newcoeff));
+                               if (expair_needs_further_processing(seq.end()-1))
                                        needs_further_processing = true;
-                               }
                        }
                        ++first;
                        p_pushed = true;
@@ -942,7 +948,6 @@ void expairseq::construct_from_exvector(const exvector &v)
        canonicalize();
        combine_same_terms_sorted_seq();
 #endif // EXPAIRSEQ_USE_HASHTAB
-       return;
 }
 
 void expairseq::construct_from_epvector(const epvector &v)
@@ -959,7 +964,6 @@ void expairseq::construct_from_epvector(const epvector &v)
        canonicalize();
        combine_same_terms_sorted_seq();
 #endif // EXPAIRSEQ_USE_HASHTAB
-       return;
 }
 
 /** Combine this expairseq with argument exvector.
@@ -1004,8 +1008,6 @@ void expairseq::make_flat(const exvector &v)
                }
                ++cit;
        }
-       
-       return;
 }
 
 /** Combine this expairseq with argument epvector.
@@ -1023,7 +1025,7 @@ void expairseq::make_flat(const epvector &v)
        while (cit!=v.end()) {
                if (cit->rest.bp->tinfo()==this->tinfo()) {
                        ++nexpairseqs;
-                       noperands += ex_to<expairseq>((*cit).rest).seq.size();
+                       noperands += ex_to<expairseq>(cit->rest).seq.size();
                }
                ++cit;
        }
@@ -1036,13 +1038,13 @@ void expairseq::make_flat(const epvector &v)
        while (cit!=v.end()) {
                if (cit->rest.bp->tinfo()==this->tinfo() &&
                    this->can_make_flat(*cit)) {
-                       const expairseq &subseqref = ex_to<expairseq>((*cit).rest);
+                       const expairseq &subseqref = ex_to<expairseq>(cit->rest);
                        combine_overall_coeff(ex_to<numeric>(subseqref.overall_coeff),
-                                                           ex_to<numeric>((*cit).coeff));
+                                                           ex_to<numeric>(cit->coeff));
                        epvector::const_iterator cit_s = subseqref.seq.begin();
                        while (cit_s!=subseqref.seq.end()) {
-                               seq.push_back(expair((*cit_s).rest,
-                                                    ex_to<numeric>((*cit_s).coeff).mul_dyn(ex_to<numeric>((*cit).coeff))));
+                               seq.push_back(expair(cit_s->rest,
+                                                    ex_to<numeric>(cit_s->coeff).mul_dyn(ex_to<numeric>(cit->coeff))));
                                //seq.push_back(combine_pair_with_coeff_to_pair(*cit_s,
                                //                                              (*cit).coeff));
                                ++cit_s;
@@ -1055,15 +1057,12 @@ void expairseq::make_flat(const epvector &v)
                }
                ++cit;
        }
-       return;
 }
 
 /** Brings this expairseq into a sorted (canonical) form. */
 void expairseq::canonicalize(void)
 {
-       // canonicalize
-       sort(seq.begin(),seq.end(),expair_is_less());
-       return;
+       sort(seq.begin(), seq.end(), expair_is_less());
 }
 
 
@@ -1083,14 +1082,14 @@ void expairseq::combine_same_terms_sorted_seq(void)
                // possible from then on the sequence has changed and must be compacted
                bool must_copy = false;
                while (itin2!=last) {
-                       if ((*itin1).rest.compare((*itin2).rest)==0) {
-                               (*itin1).coeff = ex_to<numeric>((*itin1).coeff).
-                                                add_dyn(ex_to<numeric>((*itin2).coeff));
+                       if ((*itin1).rest.compare(itin2->rest)==0) {
+                               (*itin1).coeff = ex_to<numeric>(itin1->coeff).
+                                                add_dyn(ex_to<numeric>(itin2->coeff));
                                if (expair_needs_further_processing(itin1))
                                        needs_further_processing = true;
                                must_copy = true;
                        } else {
-                               if (!ex_to<numeric>((*itin1).coeff).is_zero()) {
+                               if (!ex_to<numeric>(itin1->coeff).is_zero()) {
                                        if (must_copy)
                                                *itout = *itin1;
                                        ++itout;
@@ -1099,7 +1098,7 @@ void expairseq::combine_same_terms_sorted_seq(void)
                        }
                        ++itin2;
                }
-               if (!ex_to<numeric>((*itin1).coeff).is_zero()) {
+               if (!ex_to<numeric>(itin1->coeff).is_zero()) {
                        if (must_copy)
                                *itout = *itin1;
                        ++itout;
@@ -1113,7 +1112,6 @@ void expairseq::combine_same_terms_sorted_seq(void)
                seq.clear();
                construct_from_epvector(v);
        }
-       return;
 }
 
 #if EXPAIRSEQ_USE_HASHTAB
@@ -1196,14 +1194,13 @@ void expairseq::remove_hashtab_entry(epvector::const_iterator element)
                ++epplit;
        }
        if (!erased) {
-               printtree(cout,0);
-               cout << "tried to erase " << element-seq.begin() << std::endl;
-               cout << "size " << seq.end()-seq.begin() << std::endl;
+               std::cout << "tried to erase " << element-seq.begin() << std::endl;
+               std::cout << "size " << seq.end()-seq.begin() << std::endl;
 
-               unsigned hashindex = calc_hashindex((*element).rest);
+               unsigned hashindex = calc_hashindex(element->rest);
                epplist &eppl = hashtab[hashindex];
-               epplist::iterator epplit=eppl.begin();
-               bool erased=false;
+               epplist::iterator epplit = eppl.begin();
+               bool erased = false;
                while (epplit!=eppl.end()) {
                        if (*epplit == element) {
                                eppl.erase(epplit);
@@ -1238,10 +1235,10 @@ void expairseq::move_hashtab_entry(epvector::const_iterator oldpos,
        GINAC_ASSERT(epplit!=eppl.end());
 }
 
-void expairseq::sorted_insert(epplist &eppl, epp elem)
+void expairseq::sorted_insert(epplist &eppl, epvector::const_iterator elem)
 {
-       epplist::iterator current = eppl.begin();
-       while ((current!=eppl.end())&&((*(*current)).is_less(*elem))) {
+       epplist::const_iterator current = eppl.begin();
+       while ((current!=eppl.end()) && ((*current)->is_less(*elem))) {
                ++current;
        }
        eppl.insert(current,elem);
@@ -1252,21 +1249,21 @@ void expairseq::build_hashtab_and_combine(epvector::iterator &first_numeric,
                                           std::vector<bool> &touched,
                                           unsigned &number_of_zeroes)
 {
-       epp current=seq.begin();
+       epp current = seq.begin();
 
        while (current!=first_numeric) {
-               if (is_ex_exactly_of_type((*current).rest,numeric)) {
+               if (is_ex_exactly_of_type(current->rest,numeric)) {
                        --first_numeric;
                        iter_swap(current,first_numeric);
                } else {
                        // calculate hashindex
-                       unsigned currenthashindex = calc_hashindex((*current).rest);
+                       unsigned currenthashindex = calc_hashindex(current->rest);
 
                        // test if there is already a matching expair in the hashtab-list
                        epplist &eppl=hashtab[currenthashindex];
                        epplist::iterator epplit = eppl.begin();
                        while (epplit!=eppl.end()) {
-                               if ((*current).rest.is_equal((*(*epplit)).rest))
+                               if (current->rest.is_equal((*epplit)->rest))
                                        break;
                                ++epplit;
                        }
@@ -1276,8 +1273,8 @@ void expairseq::build_hashtab_and_combine(epvector::iterator &first_numeric,
                                ++current;
                        } else {
                                // epplit points to a matching expair, combine it with current
-                               (*(*epplit)).coeff = ex_to<numeric>((*(*epplit)).coeff).
-                                                    add_dyn(ex_to<numeric>((*current).coeff));
+                               (*epplit)->coeff = ex_to<numeric>((*epplit)->coeff).
+                                                  add_dyn(ex_to<numeric>(current->coeff));
                                
                                // move obsolete current expair to end by swapping with last_non_zero element
                                // if this was a numeric, it is swapped with the expair before first_numeric 
@@ -1287,7 +1284,7 @@ void expairseq::build_hashtab_and_combine(epvector::iterator &first_numeric,
                                --last_non_zero;
                                ++number_of_zeroes;
                                // test if combined term has coeff 0 and can be removed is done later
-                               touched[(*epplit)-seq.begin()]=true;
+                               touched[(*epplit)-seq.begin()] = true;
                        }
                }
        }
@@ -1316,8 +1313,9 @@ void expairseq::drop_coeff_0_terms(epvector::iterator &first_numeric,
                        if (current!=last_non_zero) {
                                iter_swap(current,last_non_zero);
                                --first_numeric;
-                               bool numeric_swapped=first_numeric!=last_non_zero;
-                               if (numeric_swapped) iter_swap(first_numeric,current);
+                               bool numeric_swapped = first_numeric!=last_non_zero;
+                               if (numeric_swapped)
+                                       iter_swap(first_numeric,current);
                                epvector::iterator changed_entry;
 
                                if (numeric_swapped)
@@ -1349,9 +1347,11 @@ void expairseq::drop_coeff_0_terms(epvector::iterator &first_numeric,
  *  debugging purposes. */
 bool expairseq::has_coeff_0(void) const
 {
-       for (epvector::const_iterator cit=seq.begin(); cit!=seq.end(); ++cit) {
-               if ((*cit).coeff.is_zero())
+       epvector::const_iterator i = seq.begin(), end = seq.end();
+       while (i != end) {
+               if (i->coeff.is_zero())
                        return true;
+               ++i;
        }
        return false;
 }
@@ -1359,12 +1359,11 @@ bool expairseq::has_coeff_0(void) const
 void expairseq::add_numerics_to_hashtab(epvector::iterator first_numeric,
                                                                                epvector::const_iterator last_non_zero)
 {
-       if (first_numeric==seq.end()) return; // no numerics    
+       if (first_numeric == seq.end()) return; // no numerics
        
-       epvector::iterator current = first_numeric;
-       epvector::const_iterator last = last_non_zero+1;
-       while (current!=last) {
-               sorted_insert(hashtab[hashmask],current);
+       epvector::const_iterator current = first_numeric, last = last_non_zero + 1;
+       while (current != last) {
+               sorted_insert(hashtab[hashmask], current);
                ++current;
        }
 }
@@ -1395,41 +1394,18 @@ void expairseq::combine_same_terms(void)
        epvector::iterator first_numeric = seq.end();
        epvector::iterator last_non_zero = seq.end()-1;
        
-       std::vector<bool> touched;
-       touched.reserve(seq.size());
-       for (unsigned i=0; i<seq.size(); ++i) touched[i]=false;
+       unsigned num = seq.size();
+       std::vector<bool> touched(num);
        
        unsigned number_of_zeroes = 0;
        
        GINAC_ASSERT(!has_coeff_0());
        build_hashtab_and_combine(first_numeric,last_non_zero,touched,number_of_zeroes);
-       /*
-       cout << "in combine:" << std::endl;
-       printtree(cout,0);
-       cout << "size=" << seq.end() - seq.begin() << std::endl;
-       cout << "first_numeric=" << first_numeric - seq.begin() << std::endl;
-       cout << "last_non_zero=" << last_non_zero - seq.begin() << std::endl;
-       for (unsigned i=0; i<seq.size(); ++i) {
-               if (touched[i]) cout << i << " is touched" << std::endl;
-       }
-       cout << "end in combine" << std::endl;
-       */
        
        // there should not be any terms with coeff 0 from the beginning,
        // so it should be safe to skip this step
        if (number_of_zeroes!=0) {
                drop_coeff_0_terms(first_numeric,last_non_zero,touched,number_of_zeroes);
-               /*
-               cout << "in combine after drop:" << std::endl;
-               printtree(cout,0);
-               cout << "size=" << seq.end() - seq.begin() << std::endl;
-               cout << "first_numeric=" << first_numeric - seq.begin() << std::endl;
-               cout << "last_non_zero=" << last_non_zero - seq.begin() << std::endl;
-               for (unsigned i=0; i<seq.size(); ++i) {
-                       if (touched[i]) cout << i << " is touched" << std::endl;
-               }
-               cout << "end in combine after drop" << std::endl;
-               */
        }
        
        add_numerics_to_hashtab(first_numeric,last_non_zero);
@@ -1460,25 +1436,25 @@ bool expairseq::is_canonical() const
        if (hashtabsize > 0) return 1; // not canoncalized
 #endif // EXPAIRSEQ_USE_HASHTAB
        
-       epvector::const_iterator it = seq.begin();
+       epvector::const_iterator it = seq.begin(), itend = seq.end();
        epvector::const_iterator it_last = it;
-       for (++it; it!=seq.end(); it_last=it, ++it) {
-               if (!((*it_last).is_less(*it) || (*it_last).is_equal(*it))) {
-                       if (!is_ex_exactly_of_type((*it_last).rest,numeric) ||
-                               !is_ex_exactly_of_type((*it).rest,numeric)) {
+       for (++it; it!=itend; it_last=it, ++it) {
+               if (!(it_last->is_less(*it) || it_last->is_equal(*it))) {
+                       if (!is_ex_exactly_of_type(it_last->rest,numeric) ||
+                               !is_ex_exactly_of_type(it->rest,numeric)) {
                                // double test makes it easier to set a breakpoint...
-                               if (!is_ex_exactly_of_type((*it_last).rest,numeric) ||
-                                       !is_ex_exactly_of_type((*it).rest,numeric)) {
+                               if (!is_ex_exactly_of_type(it_last->rest,numeric) ||
+                                       !is_ex_exactly_of_type(it->rest,numeric)) {
                                        printpair(std::clog, *it_last, 0);
                                        std::clog << ">";
                                        printpair(std::clog, *it, 0);
                                        std::clog << "\n";
                                        std::clog << "pair1:" << std::endl;
-                                       (*it_last).rest.print(print_tree(std::clog));
-                                       (*it_last).coeff.print(print_tree(std::clog));
+                                       it_last->rest.print(print_tree(std::clog));
+                                       it_last->coeff.print(print_tree(std::clog));
                                        std::clog << "pair2:" << std::endl;
-                                       (*it).rest.print(print_tree(std::clog));
-                                       (*it).coeff.print(print_tree(std::clog));
+                                       it->rest.print(print_tree(std::clog));
+                                       it->coeff.print(print_tree(std::clog));
                                        return 0;
                                }
                        }
@@ -1498,8 +1474,8 @@ epvector * expairseq::expandchildren(unsigned options) const
        epvector::const_iterator last = seq.end();
        epvector::const_iterator cit = seq.begin();
        while (cit!=last) {
-               const ex &expanded_ex = (*cit).rest.expand(options);
-               if (!are_ex_trivially_equal((*cit).rest,expanded_ex)) {
+               const ex &expanded_ex = cit->rest.expand(options);
+               if (!are_ex_trivially_equal(cit->rest,expanded_ex)) {
                        
                        // something changed, copy seq, eval and return it
                        epvector *s = new epvector;
@@ -1513,12 +1489,12 @@ epvector * expairseq::expandchildren(unsigned options) const
                        }
                        // copy first changed element
                        s->push_back(combine_ex_with_coeff_to_pair(expanded_ex,
-                                                                  (*cit2).coeff));
+                                                                  cit2->coeff));
                        ++cit2;
                        // copy rest
                        while (cit2!=last) {
-                               s->push_back(combine_ex_with_coeff_to_pair((*cit2).rest.expand(options),
-                                                                          (*cit2).coeff));
+                               s->push_back(combine_ex_with_coeff_to_pair(cit2->rest.expand(options),
+                                                                          cit2->coeff));
                                ++cit2;
                        }
                        return s;
@@ -1548,11 +1524,11 @@ epvector * expairseq::evalchildren(int level) const
                throw(std::runtime_error("max recursion level reached"));
        
        --level;
-       epvector::const_iterator last=seq.end();
-       epvector::const_iterator cit=seq.begin();
+       epvector::const_iterator last = seq.end();
+       epvector::const_iterator cit = seq.begin();
        while (cit!=last) {
-               const ex &evaled_ex = (*cit).rest.eval(level);
-               if (!are_ex_trivially_equal((*cit).rest,evaled_ex)) {
+               const ex &evaled_ex = cit->rest.eval(level);
+               if (!are_ex_trivially_equal(cit->rest,evaled_ex)) {
                        
                        // something changed, copy seq, eval and return it
                        epvector *s = new epvector;
@@ -1566,12 +1542,12 @@ epvector * expairseq::evalchildren(int level) const
                        }
                        // copy first changed element
                        s->push_back(combine_ex_with_coeff_to_pair(evaled_ex,
-                                                                  (*cit2).coeff));
+                                                                  cit2->coeff));
                        ++cit2;
                        // copy rest
                        while (cit2!=last) {
-                               s->push_back(combine_ex_with_coeff_to_pair((*cit2).rest.eval(level),
-                                                                          (*cit2).coeff));
+                               s->push_back(combine_ex_with_coeff_to_pair(cit2->rest.eval(level),
+                                                                          cit2->coeff));
                                ++cit2;
                        }
                        return s;
@@ -1596,7 +1572,7 @@ epvector * expairseq::subschildren(const lst &ls, const lst &lr, bool no_pattern
        // is a product or power. In this case we have to recombine the pairs
        // because the numeric coefficients may be part of the search pattern.
        bool complex_subs = false;
-       for (unsigned i=0; i<ls.nops(); i++)
+       for (unsigned i=0; i<ls.nops(); ++i)
                if (is_ex_exactly_of_type(ls.op(i), mul) || is_ex_exactly_of_type(ls.op(i), power)) {
                        complex_subs = true;
                        break;