fixed operator precedence
[ginac.git] / ginac / ncmul.cpp
index f7d1a4172d5bc5497cc0f713fd607fdee6d0ddf3..ccc91c490d4be13f853739e61b8d423c076e6fe4 100644 (file)
@@ -3,7 +3,7 @@
  *  Implementation of GiNaC's non-commutative products of expressions. */
 
 /*
- *  GiNaC Copyright (C) 1999-2001 Johannes Gutenberg University Mainz, Germany
+ *  GiNaC Copyright (C) 1999-2004 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
 #include "add.h"
 #include "mul.h"
 #include "matrix.h"
-#include "print.h"
 #include "archive.h"
-#include "debugmsg.h"
 #include "utils.h"
 
 namespace GiNaC {
 
-GINAC_IMPLEMENT_REGISTERED_CLASS(ncmul, exprseq)
+GINAC_IMPLEMENT_REGISTERED_CLASS_OPT(ncmul, exprseq,
+  print_func<print_context>(&ncmul::do_print).
+  print_func<print_tree>(&ncmul::do_print_tree).
+  print_func<print_csrc>(&ncmul::do_print_csrc).
+  print_func<print_python_repr>(&ncmul::do_print_csrc))
+
 
 //////////
-// default constructor, destructor, copy constructor assignment operator and helpers
+// default constructor
 //////////
 
 ncmul::ncmul()
 {
-       debugmsg("ncmul default constructor",LOGLEVEL_CONSTRUCT);
        tinfo_key = TINFO_ncmul;
 }
 
-DEFAULT_COPY(ncmul)
-DEFAULT_DESTROY(ncmul)
-
 //////////
 // other constructors
 //////////
@@ -59,46 +58,39 @@ DEFAULT_DESTROY(ncmul)
 
 ncmul::ncmul(const ex & lh, const ex & rh) : inherited(lh,rh)
 {
-       debugmsg("ncmul constructor from ex,ex",LOGLEVEL_CONSTRUCT);
        tinfo_key = TINFO_ncmul;
 }
 
 ncmul::ncmul(const ex & f1, const ex & f2, const ex & f3) : inherited(f1,f2,f3)
 {
-       debugmsg("ncmul constructor from 3 ex",LOGLEVEL_CONSTRUCT);
        tinfo_key = TINFO_ncmul;
 }
 
 ncmul::ncmul(const ex & f1, const ex & f2, const ex & f3,
              const ex & f4) : inherited(f1,f2,f3,f4)
 {
-       debugmsg("ncmul constructor from 4 ex",LOGLEVEL_CONSTRUCT);
        tinfo_key = TINFO_ncmul;
 }
 
 ncmul::ncmul(const ex & f1, const ex & f2, const ex & f3,
              const ex & f4, const ex & f5) : inherited(f1,f2,f3,f4,f5)
 {
-       debugmsg("ncmul constructor from 5 ex",LOGLEVEL_CONSTRUCT);
        tinfo_key = TINFO_ncmul;
 }
 
 ncmul::ncmul(const ex & f1, const ex & f2, const ex & f3,
              const ex & f4, const ex & f5, const ex & f6) : inherited(f1,f2,f3,f4,f5,f6)
 {
-       debugmsg("ncmul constructor from 6 ex",LOGLEVEL_CONSTRUCT);
        tinfo_key = TINFO_ncmul;
 }
 
 ncmul::ncmul(const exvector & v, bool discardable) : inherited(v,discardable)
 {
-       debugmsg("ncmul constructor from exvector,bool",LOGLEVEL_CONSTRUCT);
        tinfo_key = TINFO_ncmul;
 }
 
-ncmul::ncmul(exvector * vp) : inherited(vp)
+ncmul::ncmul(std::auto_ptr<exvector> vp) : inherited(vp)
 {
-       debugmsg("ncmul constructor from exvector *",LOGLEVEL_CONSTRUCT);
        tinfo_key = TINFO_ncmul;
 }
 
@@ -109,38 +101,25 @@ ncmul::ncmul(exvector * vp) : inherited(vp)
 DEFAULT_ARCHIVING(ncmul)
        
 //////////
-// functions overriding virtual functions from bases classes
+// functions overriding virtual functions from base classes
 //////////
 
 // public
 
-void ncmul::print(const print_context & c, unsigned level) const
+void ncmul::do_print(const print_context & c, unsigned level) const
 {
-       debugmsg("ncmul print", LOGLEVEL_PRINT);
-
-       if (is_of_type(c, print_tree)) {
-
-               inherited::print(c, level);
-
-       } else if (is_of_type(c, print_csrc)) {
-
-               c.s << "ncmul(";
-               exvector::const_iterator it = seq.begin(), itend = seq.end()-1;
-               while (it != itend) {
-                       it->print(c, precedence());
-                       c.s << ",";
-                       it++;
-               }
-               it->print(c, precedence());
-               c.s << ")";
+       printseq(c, '(', '*', ')', precedence(), level);
+}
 
-       } else
-               printseq(c, '(', '*', ')', precedence(), level);
+void ncmul::do_print_csrc(const print_context & c, unsigned level) const
+{
+       c.s << class_name();
+       printseq(c, '(', ',', ')', precedence(), precedence());
 }
 
 bool ncmul::info(unsigned inf) const
 {
-       throw(std::logic_error("which flags have to be implemented in ncmul::info()?"));
+       return inherited::info(inf);
 }
 
 typedef std::vector<int> intvector;
@@ -148,38 +127,38 @@ typedef std::vector<int> intvector;
 ex ncmul::expand(unsigned options) const
 {
        // First, expand the children
-       exvector expanded_seq = expandchildren(options);
+       std::auto_ptr<exvector> vp = expandchildren(options);
+       const exvector &expanded_seq = vp.get() ? *vp : this->seq;
        
        // Now, look for all the factors that are sums and remember their
-       // position and number of terms. One remark is in order here: we do not
-       // take into account the overall_coeff of the add objects. This is
-       // because in GiNaC, all terms of a sum must be of the same type, so
-       // a non-zero overall_coeff (which can only be numeric) would imply that
-       // the sum only has commutative terms. But then it would never appear
-       // as a factor of an ncmul.
+       // position and number of terms.
        intvector positions_of_adds(expanded_seq.size());
        intvector number_of_add_operands(expanded_seq.size());
 
-       int number_of_adds = 0;
-       int number_of_expanded_terms = 1;
+       size_t number_of_adds = 0;
+       size_t number_of_expanded_terms = 1;
 
-       unsigned current_position = 0;
+       size_t current_position = 0;
        exvector::const_iterator last = expanded_seq.end();
        for (exvector::const_iterator cit=expanded_seq.begin(); cit!=last; ++cit) {
-               if (is_ex_exactly_of_type(*cit, add)) {
+               if (is_exactly_a<add>(*cit)) {
                        positions_of_adds[number_of_adds] = current_position;
-                       const add & expanded_addref = ex_to<add>(*cit);
-                       number_of_add_operands[number_of_adds] = expanded_addref.seq.size();
-                       number_of_expanded_terms *= expanded_addref.seq.size();
-                       ++number_of_adds;
+                       size_t num_ops = cit->nops();
+                       number_of_add_operands[number_of_adds] = num_ops;
+                       number_of_expanded_terms *= num_ops;
+                       number_of_adds++;
                }
                ++current_position;
        }
 
        // If there are no sums, we are done
-       if (number_of_adds == 0)
-               return (new ncmul(expanded_seq, true))->
-                       setflag(status_flags::dynallocated | (options == 0 ? status_flags::expanded : 0));
+       if (number_of_adds == 0) {
+               if (vp.get())
+                       return (new ncmul(vp))->
+                               setflag(status_flags::dynallocated | (options == 0 ? status_flags::expanded : 0));
+               else
+                       return *this;
+       }
 
        // Now, form all possible products of the terms of the sums with the
        // remaining factors, and add them together
@@ -190,11 +169,8 @@ ex ncmul::expand(unsigned options) const
 
        while (true) {
                exvector term = expanded_seq;
-               for (int i=0; i<number_of_adds; i++) {
-                       GINAC_ASSERT(is_ex_exactly_of_type(expanded_seq[positions_of_adds[i]], add));
-                       const add & addref = ex_to<add>(expanded_seq[positions_of_adds[i]]);
-                       term[positions_of_adds[i]] = addref.recombine_pair_to_ex(addref.seq[k[i]]);
-               }
+               for (size_t i=0; i<number_of_adds; i++)
+                       term[positions_of_adds[i]] = expanded_seq[positions_of_adds[i]].op(k[i]);
                distrseq.push_back((new ncmul(term, true))->
                                    setflag(status_flags::dynallocated | (options == 0 ? status_flags::expanded : 0)));
 
@@ -267,15 +243,15 @@ ex ncmul::coeff(const ex & s, int n) const
 
        if (coeff_found) return (new ncmul(coeffseq,1))->setflag(status_flags::dynallocated);
        
-       return _ex0();
+       return _ex0;
 }
 
-unsigned ncmul::count_factors(const ex & e) const
+size_t ncmul::count_factors(const ex & e) const
 {
-       if ((is_ex_exactly_of_type(e,mul)&&(e.return_type()!=return_types::commutative))||
-               (is_ex_exactly_of_type(e,ncmul))) {
-               unsigned factors=0;
-               for (unsigned i=0; i<e.nops(); i++)
+       if ((is_exactly_a<mul>(e)&&(e.return_type()!=return_types::commutative))||
+               (is_exactly_a<ncmul>(e))) {
+               size_t factors=0;
+               for (size_t i=0; i<e.nops(); i++)
                        factors += count_factors(e.op(i));
                
                return factors;
@@ -285,10 +261,10 @@ unsigned ncmul::count_factors(const ex & e) const
                
 void ncmul::append_factors(exvector & v, const ex & e) const
 {
-       if ((is_ex_exactly_of_type(e,mul)&&(e.return_type()!=return_types::commutative))||
-               (is_ex_exactly_of_type(e,ncmul))) {
-               for (unsigned i=0; i<e.nops(); i++)
-                       append_factors(v,e.op(i));
+       if ((is_exactly_a<mul>(e)&&(e.return_type()!=return_types::commutative))||
+               (is_exactly_a<ncmul>(e))) {
+               for (size_t i=0; i<e.nops(); i++)
+                       append_factors(v, e.op(i));
        } else 
                v.push_back(e);
 }
@@ -296,18 +272,20 @@ void ncmul::append_factors(exvector & v, const ex & e) const
 typedef std::vector<unsigned> unsignedvector;
 typedef std::vector<exvector> exvectorvector;
 
+/** Perform automatic term rewriting rules in this class.  In the following
+ *  x, x1, x2,... stand for a symbolic variables of type ex and c, c1, c2...
+ *  stand for such expressions that contain a plain number.
+ *  - ncmul(...,*(x1,x2),...,ncmul(x3,x4),...) -> ncmul(...,x1,x2,...,x3,x4,...)  (associativity)
+ *  - ncmul(x) -> x
+ *  - ncmul() -> 1
+ *  - ncmul(...,c1,...,c2,...) -> *(c1,c2,ncmul(...))  (pull out commutative elements)
+ *  - ncmul(x1,y1,x2,y2) -> *(ncmul(x1,x2),ncmul(y1,y2))  (collect elements of same type)
+ *  - ncmul(x1,x2,x3,...) -> x::eval_ncmul(x1,x2,x3,...)
+ *
+ *  @param level cut-off in recursive evaluation */
 ex ncmul::eval(int level) const
 {
-       // simplifications: ncmul(...,*(x1,x2),...,ncmul(x3,x4),...) ->
-       //                      ncmul(...,x1,x2,...,x3,x4,...) (associativity)
-       //                  ncmul(x) -> x
-       //                  ncmul() -> 1
-       //                  ncmul(...,c1,...,c2,...)
-       //                      *(c1,c2,ncmul(...)) (pull out commutative elements)
-       //                  ncmul(x1,y1,x2,y2) -> *(ncmul(x1,x2),ncmul(y1,y2))
-       //                      (collect elements of same type)
-       //                  ncmul(x1,x2,x3,...) -> x::simplify_ncmul(x1,x2,x3,...)
-       // the following rule would be nice, but produces a recursion,
+       // The following additional rule would be nice, but produces a recursion,
        // which must be trapped by introducing a flag that the sub-ncmuls()
        // are already evaluated (maybe later...)
        //                  ncmul(x1,x2,...,X,y1,y2,...) ->
@@ -321,8 +299,8 @@ ex ncmul::eval(int level) const
        exvector evaledseq=evalchildren(level);
 
        // ncmul(...,*(x1,x2),...,ncmul(x3,x4),...) ->
-       //     ncmul(...,x1,x2,...,x3,x4,...) (associativity)
-       unsigned factors = 0;
+       //     ncmul(...,x1,x2,...,x3,x4,...)  (associativity)
+       size_t factors = 0;
        exvector::const_iterator cit = evaledseq.begin(), citend = evaledseq.end();
        while (cit != citend)
                factors += count_factors(*cit++);
@@ -337,15 +315,15 @@ ex ncmul::eval(int level) const
        if (assocseq.size()==1) return *(seq.begin());
 
        // ncmul() -> 1
-       if (assocseq.empty()) return _ex1();
+       if (assocseq.empty()) return _ex1;
 
        // determine return types
        unsignedvector rettypes;
        rettypes.reserve(assocseq.size());
-       unsigned i = 0;
-       unsigned count_commutative=0;
-       unsigned count_noncommutative=0;
-       unsigned count_noncommutative_composite=0;
+       size_t i = 0;
+       size_t count_commutative=0;
+       size_t count_noncommutative=0;
+       size_t count_noncommutative_composite=0;
        cit = assocseq.begin(); citend = assocseq.end();
        while (cit != citend) {
                switch (rettypes[i] = cit->return_type()) {
@@ -372,8 +350,8 @@ ex ncmul::eval(int level) const
                commutativeseq.reserve(count_commutative+1);
                exvector noncommutativeseq;
                noncommutativeseq.reserve(assocseq.size()-count_commutative);
-               unsigned num = assocseq.size();
-               for (unsigned i=0; i<num; ++i) {
+               size_t num = assocseq.size();
+               for (size_t i=0; i<num; ++i) {
                        if (rettypes[i]==return_types::commutative)
                                commutativeseq.push_back(assocseq[i]);
                        else
@@ -391,7 +369,7 @@ ex ncmul::eval(int level) const
                // elements in assocseq
                GINAC_ASSERT(count_commutative==0);
 
-               unsigned assoc_num = assocseq.size();
+               size_t assoc_num = assocseq.size();
                exvectorvector evv;
                unsignedvector rttinfos;
                evv.reserve(assoc_num);
@@ -400,7 +378,7 @@ ex ncmul::eval(int level) const
                cit = assocseq.begin(), citend = assocseq.end();
                while (cit != citend) {
                        unsigned ti = cit->return_type_tinfo();
-                       unsigned rtt_num = rttinfos.size();
+                       size_t rtt_num = rttinfos.size();
                        // search type in vector of known types
                        for (i=0; i<rtt_num; ++i) {
                                if (ti == rttinfos[i]) {
@@ -418,11 +396,11 @@ ex ncmul::eval(int level) const
                        ++cit;
                }
 
-               unsigned evv_num = evv.size();
+               size_t evv_num = evv.size();
 #ifdef DO_GINAC_ASSERT
                GINAC_ASSERT(evv_num == rttinfos.size());
                GINAC_ASSERT(evv_num > 0);
-               unsigned s=0;
+               size_t s=0;
                for (i=0; i<evv_num; ++i)
                        s += evv[i].size();
                GINAC_ASSERT(s == assoc_num);
@@ -430,7 +408,7 @@ ex ncmul::eval(int level) const
                
                // if all elements are of same type, simplify the string
                if (evv_num == 1)
-                       return evv[0][0].simplify_ncmul(evv[0]);
+                       return evv[0][0].eval_ncmul(evv[0]);
                
                exvector splitseq;
                splitseq.reserve(evv_num);
@@ -444,10 +422,10 @@ ex ncmul::eval(int level) const
                                                                                  status_flags::evaluated);
 }
 
-ex ncmul::evalm(void) const
+ex ncmul::evalm() const
 {
        // Evaluate children first
-       exvector *s = new exvector;
+       std::auto_ptr<exvector> s(new exvector);
        s->reserve(seq.size());
        exvector::const_iterator it = seq.begin(), itend = seq.end();
        while (it != itend) {
@@ -457,16 +435,15 @@ ex ncmul::evalm(void) const
 
        // If there are only matrices, simply multiply them
        it = s->begin(); itend = s->end();
-       if (is_ex_of_type(*it, matrix)) {
+       if (is_a<matrix>(*it)) {
                matrix prod(ex_to<matrix>(*it));
                it++;
                while (it != itend) {
-                       if (!is_ex_of_type(*it, matrix))
+                       if (!is_a<matrix>(*it))
                                goto no_matrix;
                        prod = prod.mul(ex_to<matrix>(*it));
                        it++;
                }
-               delete s;
                return prod;
        }
 
@@ -474,16 +451,35 @@ no_matrix:
        return (new ncmul(s))->setflag(status_flags::dynallocated);
 }
 
-ex ncmul::thisexprseq(const exvector & v) const
+ex ncmul::thiscontainer(const exvector & v) const
 {
        return (new ncmul(v))->setflag(status_flags::dynallocated);
 }
 
-ex ncmul::thisexprseq(exvector * vp) const
+ex ncmul::thiscontainer(std::auto_ptr<exvector> vp) const
 {
        return (new ncmul(vp))->setflag(status_flags::dynallocated);
 }
 
+ex ncmul::conjugate() const
+{
+       if (return_type() != return_types::noncommutative) {
+               return exprseq::conjugate();
+       }
+
+       if ((return_type_tinfo() & 0xffffff00U) != TINFO_clifford) {
+               return exprseq::conjugate();
+       }
+
+       exvector ev;
+       ev.reserve(nops());
+       for (const_iterator i=end(); i!=begin();) {
+               --i;
+               ev.push_back(i->conjugate());
+       }
+       return (new ncmul(ev, true))->setflag(status_flags::dynallocated).eval();
+}
+
 // protected
 
 /** Implementation of ex::diff() for a non-commutative product. It applies
@@ -491,13 +487,13 @@ ex ncmul::thisexprseq(exvector * vp) const
  *  @see ex::diff */
 ex ncmul::derivative(const symbol & s) const
 {
-       unsigned num = seq.size();
+       size_t num = seq.size();
        exvector addseq;
        addseq.reserve(num);
        
        // D(a*b*c) = D(a)*b*c + a*D(b)*c + a*b*D(c)
        exvector ncmulseq = seq;
-       for (unsigned i=0; i<num; ++i) {
+       for (size_t i=0; i<num; ++i) {
                ex e = seq[i].diff(s);
                e.swap(ncmulseq[i]);
                addseq.push_back((new ncmul(ncmulseq))->setflag(status_flags::dynallocated));
@@ -511,7 +507,7 @@ int ncmul::compare_same_type(const basic & other) const
        return inherited::compare_same_type(other);
 }
 
-unsigned ncmul::return_type(void) const
+unsigned ncmul::return_type() const
 {
        if (seq.empty())
                return return_types::commutative;
@@ -543,7 +539,7 @@ unsigned ncmul::return_type(void) const
        return all_commutative ? return_types::commutative : return_types::noncommutative;
 }
    
-unsigned ncmul::return_type_tinfo(void) const
+unsigned ncmul::return_type_tinfo() const
 {
        if (seq.empty())
                return tinfo_key;
@@ -570,19 +566,37 @@ unsigned ncmul::return_type_tinfo(void) const
 // non-virtual functions in this class
 //////////
 
-exvector ncmul::expandchildren(unsigned options) const
+std::auto_ptr<exvector> ncmul::expandchildren(unsigned options) const
 {
-       exvector s;
-       s.reserve(seq.size());
-       exvector::const_iterator it = seq.begin(), itend = seq.end();
-       while (it != itend) {
-               s.push_back(it->expand(options));
-               it++;
+       const_iterator cit = this->seq.begin(), end = this->seq.end();
+       while (cit != end) {
+               const ex & expanded_ex = cit->expand(options);
+               if (!are_ex_trivially_equal(*cit, expanded_ex)) {
+
+                       // copy first part of seq which hasn't changed
+                       std::auto_ptr<exvector> s(new exvector(this->seq.begin(), cit));
+                       reserve(*s, this->seq.size());
+
+                       // insert changed element
+                       s->push_back(expanded_ex);
+                       ++cit;
+
+                       // copy rest
+                       while (cit != end) {
+                               s->push_back(cit->expand(options));
+                               ++cit;
+                       }
+
+                       return s;
+               }
+
+               ++cit;
        }
-       return s;
+
+       return std::auto_ptr<exvector>(0); // nothing has changed
 }
 
-const exvector & ncmul::get_factors(void) const
+const exvector & ncmul::get_factors() const
 {
        return seq;
 }
@@ -591,15 +605,15 @@ const exvector & ncmul::get_factors(void) const
 // friend functions
 //////////
 
-ex nonsimplified_ncmul(const exvector & v)
+ex reeval_ncmul(const exvector & v)
 {
        return (new ncmul(v))->setflag(status_flags::dynallocated);
 }
 
-ex simplified_ncmul(const exvector & v)
+ex hold_ncmul(const exvector & v)
 {
        if (v.empty())
-               return _ex1();
+               return _ex1;
        else if (v.size() == 1)
                return v[0];
        else