]> www.ginac.de Git - ginac.git/blobdiff - ginac/mul.cpp
Added methods for taking real and imaginary parts.
[ginac.git] / ginac / mul.cpp
index db68b275ffbbc788a476bad5b9b9f814b30229ff..d2dd675cfa08b9af4265a599e8011b99c06e14d8 100644 (file)
@@ -3,7 +3,7 @@
  *  Implementation of GiNaC's products of expressions. */
 
 /*
- *  GiNaC Copyright (C) 1999-2003 Johannes Gutenberg University Mainz, Germany
+ *  GiNaC Copyright (C) 1999-2006 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
@@ -17,7 +17,7 @@
  *
  *  You should have received a copy of the GNU General Public License
  *  along with this program; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  */
 
 #include <iostream>
@@ -30,6 +30,7 @@
 #include "power.h"
 #include "operators.h"
 #include "matrix.h"
+#include "indexed.h"
 #include "lst.h"
 #include "archive.h"
 #include "utils.h"
@@ -40,7 +41,7 @@ GINAC_IMPLEMENT_REGISTERED_CLASS_OPT(mul, expairseq,
   print_func<print_context>(&mul::do_print).
   print_func<print_latex>(&mul::do_print_latex).
   print_func<print_csrc>(&mul::do_print_csrc).
-  print_func<print_tree>(&inherited::do_print_tree).
+  print_func<print_tree>(&mul::do_print_tree).
   print_func<print_python_repr>(&mul::do_print_python_repr))
 
 
@@ -50,7 +51,7 @@ GINAC_IMPLEMENT_REGISTERED_CLASS_OPT(mul, expairseq,
 
 mul::mul()
 {
-       tinfo_key = TINFO_mul;
+       tinfo_key = &mul::tinfo_static;
 }
 
 //////////
@@ -61,7 +62,7 @@ mul::mul()
 
 mul::mul(const ex & lh, const ex & rh)
 {
-       tinfo_key = TINFO_mul;
+       tinfo_key = &mul::tinfo_static;
        overall_coeff = _ex1;
        construct_from_2_ex(lh,rh);
        GINAC_ASSERT(is_canonical());
@@ -69,7 +70,7 @@ mul::mul(const ex & lh, const ex & rh)
 
 mul::mul(const exvector & v)
 {
-       tinfo_key = TINFO_mul;
+       tinfo_key = &mul::tinfo_static;
        overall_coeff = _ex1;
        construct_from_exvector(v);
        GINAC_ASSERT(is_canonical());
@@ -77,7 +78,7 @@ mul::mul(const exvector & v)
 
 mul::mul(const epvector & v)
 {
-       tinfo_key = TINFO_mul;
+       tinfo_key = &mul::tinfo_static;
        overall_coeff = _ex1;
        construct_from_epvector(v);
        GINAC_ASSERT(is_canonical());
@@ -85,7 +86,7 @@ mul::mul(const epvector & v)
 
 mul::mul(const epvector & v, const ex & oc)
 {
-       tinfo_key = TINFO_mul;
+       tinfo_key = &mul::tinfo_static;
        overall_coeff = oc;
        construct_from_epvector(v);
        GINAC_ASSERT(is_canonical());
@@ -93,8 +94,8 @@ mul::mul(const epvector & v, const ex & oc)
 
 mul::mul(std::auto_ptr<epvector> vp, const ex & oc)
 {
-       tinfo_key = TINFO_mul;
-       GINAC_ASSERT(vp!=0);
+       tinfo_key = &mul::tinfo_static;
+       GINAC_ASSERT(vp.get()!=0);
        overall_coeff = oc;
        construct_from_epvector(*vp);
        GINAC_ASSERT(is_canonical());
@@ -102,7 +103,7 @@ mul::mul(std::auto_ptr<epvector> vp, const ex & oc)
 
 mul::mul(const ex & lh, const ex & mh, const ex & rh)
 {
-       tinfo_key = TINFO_mul;
+       tinfo_key = &mul::tinfo_static;
        exvector factors;
        factors.reserve(3);
        factors.push_back(lh);
@@ -128,8 +129,8 @@ void mul::print_overall_coeff(const print_context & c, const char *mul_sym) cons
        const numeric &coeff = ex_to<numeric>(overall_coeff);
        if (coeff.csgn() == -1)
                c.s << '-';
-       if (!coeff.is_equal(_num1) &&
-               !coeff.is_equal(_num_1)) {
+       if (!coeff.is_equal(*_num1_p) &&
+               !coeff.is_equal(*_num_1_p)) {
                if (coeff.is_rational()) {
                        if (coeff.is_negative())
                                (-coeff).print(c);
@@ -421,7 +422,7 @@ ex mul::eval(int level) const
                return recombine_pair_to_ex(*(seq.begin()));
        } else if ((seq_size==1) &&
                   is_exactly_a<add>((*seq.begin()).rest) &&
-                  ex_to<numeric>((*seq.begin()).coeff).is_equal(_num1)) {
+                  ex_to<numeric>((*seq.begin()).coeff).is_equal(*_num1_p)) {
                // *(+(x,y,...);c) -> +(*(x,c),*(y,c),...) (c numeric(), no powers of +())
                const add & addref = ex_to<add>((*seq.begin()).rest);
                std::auto_ptr<epvector> distrseq(new epvector);
@@ -460,6 +461,41 @@ ex mul::evalf(int level) const
        return mul(s, overall_coeff.evalf(level));
 }
 
+void mul::find_real_imag(ex & rp, ex & ip) const
+{
+       rp = overall_coeff.real_part();
+       ip = overall_coeff.imag_part();
+       for (epvector::const_iterator i=seq.begin(); i!=seq.end(); ++i) {
+               ex factor = recombine_pair_to_ex(*i);
+               ex new_rp = factor.real_part();
+               ex new_ip = factor.imag_part();
+               if(new_ip.is_zero()) {
+                       rp *= new_rp;
+                       ip *= new_rp;
+               } else {
+                       ex temp = rp*new_rp - ip*new_ip;
+                       ip = ip*new_rp + rp*new_ip;
+                       rp = temp;
+               }
+       }
+       rp = rp.expand();
+       ip = ip.expand();
+}
+
+ex mul::real_part() const
+{
+       ex rp, ip;
+       find_real_imag(rp, ip);
+       return rp;
+}
+
+ex mul::imag_part() const
+{
+       ex rp, ip;
+       find_real_imag(rp, ip);
+       return ip;
+}
+
 ex mul::evalm() const
 {
        // numeric*matrix
@@ -558,6 +594,58 @@ bool tryfactsubs(const ex & origfactor, const ex & patternfactor, int & nummatch
        return true;
 }
 
+/** Checks wheter e matches to the pattern pat and the (possibly to be updated
+  * list of replacements repls. This matching is in the sense of algebraic
+  * substitutions. Matching starts with pat.op(factor) of the pattern because
+  * the factors before this one have already been matched. The (possibly
+  * updated) number of matches is in nummatches. subsed[i] is true for factors
+  * that already have been replaced by previous substitutions and matched[i]
+  * is true for factors that have been matched by the current match.
+  */
+bool algebraic_match_mul_with_mul(const mul &e, const ex &pat, lst &repls,
+               int factor, int &nummatches, const std::vector<bool> &subsed,
+               std::vector<bool> &matched)
+{
+       if (factor == pat.nops())
+               return true;
+
+       for (size_t i=0; i<e.nops(); ++i) {
+               if(subsed[i] || matched[i])
+                       continue;
+               lst newrepls = repls;
+               int newnummatches = nummatches;
+               if (tryfactsubs(e.op(i), pat.op(factor), newnummatches, newrepls)) {
+                       matched[i] = true;
+                       if (algebraic_match_mul_with_mul(e, pat, newrepls, factor+1,
+                                       newnummatches, subsed, matched)) {
+                               repls = newrepls;
+                               nummatches = newnummatches;
+                               return true;
+                       }
+                       else
+                               matched[i] = false;
+               }
+       }
+
+       return false;
+}
+
+bool mul::has(const ex & pattern, unsigned options) const
+{
+       if(!(options&has_options::algebraic))
+               return basic::has(pattern,options);
+       if(is_a<mul>(pattern)) {
+               lst repls;
+               int nummatches = std::numeric_limits<int>::max();
+               std::vector<bool> subsed(seq.size(), false);
+               std::vector<bool> matched(seq.size(), false);
+               if(algebraic_match_mul_with_mul(*this, pattern, repls, 0, nummatches,
+                               subsed, matched))
+                       return true;
+       }
+       return basic::has(pattern, options);
+}
+
 ex mul::algebraic_subs_mul(const exmap & m, unsigned options) const
 {      
        std::vector<bool> subsed(seq.size(), false);
@@ -566,29 +654,13 @@ ex mul::algebraic_subs_mul(const exmap & m, unsigned options) const
        for (exmap::const_iterator it = m.begin(); it != m.end(); ++it) {
 
                if (is_exactly_a<mul>(it->first)) {
-
+retry1:
                        int nummatches = std::numeric_limits<int>::max();
                        std::vector<bool> currsubsed(seq.size(), false);
                        bool succeed = true;
                        lst repls;
-
-                       for (size_t j=0; j<it->first.nops(); j++) {
-                               bool found=false;
-                               for (size_t k=0; k<nops(); k++) {
-                                       if (currsubsed[k] || subsed[k])
-                                               continue;
-                                       if (tryfactsubs(op(k), it->first.op(j), nummatches, repls)) {
-                                               currsubsed[k] = true;
-                                               found = true;
-                                               break;
-                                       }
-                               }
-                               if (!found) {
-                                       succeed = false;
-                                       break;
-                               }
-                       }
-                       if (!succeed)
+                       
+                       if(!algebraic_match_mul_with_mul(*this, it->first, repls, 0, nummatches, subsed, currsubsed))
                                continue;
 
                        bool foundfirstsubsedfactor = false;
@@ -603,9 +675,10 @@ ex mul::algebraic_subs_mul(const exmap & m, unsigned options) const
                                        subsed[j] = true;
                                }
                        }
+                       goto retry1;
 
                } else {
-
+retry2:
                        int nummatches = std::numeric_limits<int>::max();
                        lst repls;
 
@@ -613,6 +686,7 @@ ex mul::algebraic_subs_mul(const exmap & m, unsigned options) const
                                if (!subsed[j] && tryfactsubs(op(j), it->first, nummatches, repls)) {
                                        subsed[j] = true;
                                        subsresult[j] = op(j) * power(it->second.subs(ex(repls), subs_options::no_pattern) / it->first.subs(ex(repls), subs_options::no_pattern), nummatches);
+                                       goto retry2;
                                }
                        }
                }
@@ -672,7 +746,7 @@ int mul::compare_same_type(const basic & other) const
 unsigned mul::return_type() const
 {
        if (seq.empty()) {
-               // mul without factors: should not happen, but commutes
+               // mul without factors: should not happen, but commutates
                return return_types::commutative;
        }
        
@@ -692,8 +766,8 @@ unsigned mul::return_type() const
                if ((rt == return_types::noncommutative) && (!all_commutative)) {
                        // another nc element found, compare type_infos
                        if (noncommutative_element->rest.return_type_tinfo() != i->rest.return_type_tinfo()) {
-                               // diffent types -> mul is ncc
-                               return return_types::noncommutative_composite;
+                                       // different types -> mul is ncc
+                                       return return_types::noncommutative_composite;
                        }
                }
                ++i;
@@ -702,10 +776,10 @@ unsigned mul::return_type() const
        return all_commutative ? return_types::commutative : return_types::noncommutative;
 }
    
-unsigned mul::return_type_tinfo() const
+tinfo_t mul::return_type_tinfo() const
 {
        if (seq.empty())
-               return tinfo_key;  // mul without factors: should not happen
+               return this;  // mul without factors: should not happen
        
        // return type_info of first noncommutative element
        epvector::const_iterator i = seq.begin(), end = seq.end();
@@ -715,7 +789,7 @@ unsigned mul::return_type_tinfo() const
                ++i;
        }
        // no noncommutative element found, should not happen
-       return tinfo_key;
+       return this;
 }
 
 ex mul::thisexpairseq(const epvector & v, const ex & oc) const
@@ -766,7 +840,7 @@ expair mul::combine_pair_with_coeff_to_pair(const expair & p,
        
 ex mul::recombine_pair_to_ex(const expair & p) const
 {
-       if (ex_to<numeric>(p.coeff).is_equal(_num1)) 
+       if (ex_to<numeric>(p.coeff).is_equal(*_num1_p)) 
                return p.rest;
        else
                return (new power(p.rest,p.coeff))->setflag(status_flags::dynallocated);
@@ -821,7 +895,21 @@ bool mul::can_make_flat(const expair & p) const
        // this assertion will probably fail somewhere
        // it would require a more careful make_flat, obeying the power laws
        // probably should return true only if p.coeff is integer
-       return ex_to<numeric>(p.coeff).is_equal(_num1);
+       return ex_to<numeric>(p.coeff).is_equal(*_num1_p);
+}
+
+bool mul::can_be_further_expanded(const ex & e)
+{
+       if (is_exactly_a<mul>(e)) {
+               for (epvector::const_iterator cit = ex_to<mul>(e).seq.begin(); cit != ex_to<mul>(e).seq.end(); ++cit) {
+                       if (is_exactly_a<add>(cit->rest) && cit->coeff.info(info_flags::posint))
+                               return true;
+               }
+       } else if (is_exactly_a<power>(e)) {
+               if (is_exactly_a<add>(e.op(0)) && e.op(1).info(info_flags::posint))
+                       return true;
+       }
+       return false;
 }
 
 ex mul::expand(unsigned options) const
@@ -833,18 +921,14 @@ ex mul::expand(unsigned options) const
        // Now, look for all the factors that are sums and multiply each one out
        // with the next one that is found while collecting the factors which are
        // not sums
-       int number_of_adds = 0;
        ex last_expanded = _ex1;
 
        epvector non_adds;
        non_adds.reserve(expanded_seq.size());
-       bool non_adds_has_sums = false; // Look for sums or powers of sums in the non_adds (we need this later)
 
-       epvector::const_iterator cit = expanded_seq.begin(), last = expanded_seq.end();
-       while (cit != last) {
+       for (epvector::const_iterator cit = expanded_seq.begin(); cit != expanded_seq.end(); ++cit) {
                if (is_exactly_a<add>(cit->rest) &&
                        (cit->coeff.is_equal(_ex1))) {
-                       ++number_of_adds;
                        if (is_exactly_a<add>(last_expanded)) {
 
                                // Expand a product of two sums, aggressive version.
@@ -862,6 +946,7 @@ ex mul::expand(unsigned options) const
                                const epvector::const_iterator add2end   = add2.seq.end();
                                epvector distrseq;
                                distrseq.reserve(add1.seq.size()+add2.seq.size());
+
                                // Multiply add2 with the overall coefficient of add1 and append it to distrseq:
                                if (!add1.overall_coeff.is_zero()) {
                                        if (add1.overall_coeff.is_equal(_ex1))
@@ -870,6 +955,7 @@ ex mul::expand(unsigned options) const
                                                for (epvector::const_iterator i=add2begin; i!=add2end; ++i)
                                                        distrseq.push_back(expair(i->rest, ex_to<numeric>(i->coeff).mul_dyn(ex_to<numeric>(add1.overall_coeff))));
                                }
+
                                // Multiply add1 with the overall coefficient of add2 and append it to distrseq:
                                if (!add2.overall_coeff.is_zero()) {
                                        if (add2.overall_coeff.is_equal(_ex1))
@@ -878,69 +964,93 @@ ex mul::expand(unsigned options) const
                                                for (epvector::const_iterator i=add1begin; i!=add1end; ++i)
                                                        distrseq.push_back(expair(i->rest, ex_to<numeric>(i->coeff).mul_dyn(ex_to<numeric>(add2.overall_coeff))));
                                }
+
                                // Compute the new overall coefficient and put it together:
                                ex tmp_accu = (new add(distrseq, add1.overall_coeff*add2.overall_coeff))->setflag(status_flags::dynallocated);
+
+                               exvector add1_dummy_indices, add2_dummy_indices, add_indices;
+
+                               for (epvector::const_iterator i=add1begin; i!=add1end; ++i) {
+                                       add_indices = get_all_dummy_indices(i->rest);
+                                       add1_dummy_indices.insert(add1_dummy_indices.end(), add_indices.begin(), add_indices.end());
+                               }
+                               for (epvector::const_iterator i=add2begin; i!=add2end; ++i) {
+                                       add_indices = get_all_dummy_indices(i->rest);
+                                       add2_dummy_indices.insert(add2_dummy_indices.end(), add_indices.begin(), add_indices.end());
+                               }
+
+                               sort(add1_dummy_indices.begin(), add1_dummy_indices.end(), ex_is_less());
+                               sort(add2_dummy_indices.begin(), add2_dummy_indices.end(), ex_is_less());
+                               lst dummy_subs = rename_dummy_indices_uniquely(add1_dummy_indices, add2_dummy_indices);
+
                                // Multiply explicitly all non-numeric terms of add1 and add2:
-                               for (epvector::const_iterator i1=add1begin; i1!=add1end; ++i1) {
+                               for (epvector::const_iterator i2=add2begin; i2!=add2end; ++i2) {
                                        // We really have to combine terms here in order to compactify
                                        // the result.  Otherwise it would become waayy tooo bigg.
                                        numeric oc;
                                        distrseq.clear();
-                                       for (epvector::const_iterator i2=add2begin; i2!=add2end; ++i2) {
+                                       ex i2_new = (dummy_subs.op(0).nops()>0? 
+                                                                i2->rest.subs((lst)dummy_subs.op(0), (lst)dummy_subs.op(1), subs_options::no_pattern) : i2->rest);
+                                       for (epvector::const_iterator i1=add1begin; i1!=add1end; ++i1) {
                                                // Don't push_back expairs which might have a rest that evaluates to a numeric,
                                                // since that would violate an invariant of expairseq:
-                                               const ex rest = ex((new mul(i1->rest, i2->rest))->setflag(status_flags::dynallocated)).expand();
-                                               if (is_exactly_a<numeric>(rest))
+                                               const ex rest = (new mul(i1->rest, i2_new))->setflag(status_flags::dynallocated);
+                                               if (is_exactly_a<numeric>(rest)) {
                                                        oc += ex_to<numeric>(rest).mul(ex_to<numeric>(i1->coeff).mul(ex_to<numeric>(i2->coeff)));
-                                               else
+                                               } else {
                                                        distrseq.push_back(expair(rest, ex_to<numeric>(i1->coeff).mul_dyn(ex_to<numeric>(i2->coeff))));
+                                               }
                                        }
                                        tmp_accu += (new add(distrseq, oc))->setflag(status_flags::dynallocated);
                                }
                                last_expanded = tmp_accu;
 
                        } else {
-                               non_adds.push_back(split_ex_to_pair(last_expanded));
+                               if (!last_expanded.is_equal(_ex1))
+                                       non_adds.push_back(split_ex_to_pair(last_expanded));
                                last_expanded = cit->rest;
                        }
+
                } else {
-                       if (is_exactly_a<add>(cit->rest))
-                               non_adds_has_sums = true;
                        non_adds.push_back(*cit);
                }
-               ++cit;
        }
 
        // Now the only remaining thing to do is to multiply the factors which
        // were not sums into the "last_expanded" sum
        if (is_exactly_a<add>(last_expanded)) {
-               const add & finaladd = ex_to<add>(last_expanded);
-
-               size_t n = finaladd.nops();
+               size_t n = last_expanded.nops();
                exvector distrseq;
                distrseq.reserve(n);
+               exvector va = get_all_dummy_indices(mul(non_adds));
+               sort(va.begin(), va.end(), ex_is_less());
 
                for (size_t i=0; i<n; ++i) {
                        epvector factors = non_adds;
-                       expair new_factor = split_ex_to_pair(finaladd.op(i).expand());
-                       factors.push_back(new_factor);
-
-                       const mul & term = static_cast<const mul &>((new mul(factors, overall_coeff))->setflag(status_flags::dynallocated));
-
-                       // The new term may have sums in it if e.g. a sqrt() of a sum in
-                       // the non_adds meets a sqrt() of a sum in the factor from
-                       // last_expanded. In this case we should re-expand the term.
-                       if (non_adds_has_sums || is_exactly_a<add>(new_factor.rest))
-                               distrseq.push_back(ex(term).expand());
-                       else
-                               distrseq.push_back(term.setflag(options == 0 ? status_flags::expanded : 0));
+                       factors.push_back(split_ex_to_pair(rename_dummy_indices_uniquely(va, last_expanded.op(i))));
+                       ex term = (new mul(factors, overall_coeff))->setflag(status_flags::dynallocated);
+                       if (can_be_further_expanded(term)) {
+                               distrseq.push_back(term.expand());
+                       } else {
+                               if (options == 0)
+                                       ex_to<basic>(term).setflag(status_flags::expanded);
+                               distrseq.push_back(term);
+                       }
                }
+
                return ((new add(distrseq))->
                        setflag(status_flags::dynallocated | (options == 0 ? status_flags::expanded : 0)));
        }
+
        non_adds.push_back(split_ex_to_pair(last_expanded));
-       return (new mul(non_adds, overall_coeff))->
-               setflag(status_flags::dynallocated | (options == 0 ? status_flags::expanded : 0));
+       ex result = (new mul(non_adds, overall_coeff))->setflag(status_flags::dynallocated);
+       if (can_be_further_expanded(result)) {
+               return result.expand();
+       } else {
+               if (options == 0)
+                       ex_to<basic>(result).setflag(status_flags::expanded);
+               return result;
+       }
 }