]> www.ginac.de Git - ginac.git/blobdiff - ginac/basic.cpp
Replace use of NULL by C++11 nullptr.
[ginac.git] / ginac / basic.cpp
index 09d9b79b996d66def75002892060c9ed16f28997..563dd7d5b6455fe9453885111bb0aac7a4259ed9 100644 (file)
@@ -3,7 +3,7 @@
  *  Implementation of GiNaC's ABC. */
 
 /*
- *  GiNaC Copyright (C) 1999-2003 Johannes Gutenberg University Mainz, Germany
+ *  GiNaC Copyright (C) 1999-2015 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
  *
  *  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>
-#include <stdexcept>
-#ifdef DO_GINAC_ASSERT
-#  include <typeinfo>
-#endif
-
 #include "basic.h"
 #include "ex.h"
 #include "numeric.h"
 #include "power.h"
+#include "add.h"
 #include "symbol.h"
 #include "lst.h"
 #include "ncmul.h"
 #include "wildcard.h"
 #include "archive.h"
 #include "utils.h"
+#include "hash_seed.h"
+#include "inifcns.h"
+
+#include <iostream>
+#include <stdexcept>
+#include <typeinfo>
 
 namespace GiNaC {
 
@@ -55,26 +56,25 @@ GINAC_IMPLEMENT_REGISTERED_CLASS_OPT(basic, void,
 /** basic copy constructor: implicitly assumes that the other class is of
  *  the exact same type (as it's used by duplicate()), so it can copy the
  *  tinfo_key and the hash value. */
-basic::basic(const basic & other) : tinfo_key(other.tinfo_key), flags(other.flags & ~status_flags::dynallocated), hashvalue(other.hashvalue), refcount(0)
+basic::basic(const basic & other) : flags(other.flags & ~status_flags::dynallocated), hashvalue(other.hashvalue)
 {
-       GINAC_ASSERT(typeid(*this) == typeid(other));
 }
 
 /** basic assignment operator: the other object might be of a derived class. */
 const basic & basic::operator=(const basic & other)
 {
        unsigned fl = other.flags & ~status_flags::dynallocated;
-       if (tinfo_key != other.tinfo_key) {
+       if (typeid(*this) != typeid(other)) {
                // The other object is of a derived class, so clear the flags as they
                // might no longer apply (especially hash_calculated). Oh, and don't
                // copy the tinfo_key: it is already set correctly for this object.
-               flags = 0;
+               fl &= ~(status_flags::evaluated | status_flags::expanded | status_flags::hash_calculated);
        } else {
                // The objects are of the exact same class, so copy the hash value.
                hashvalue = other.hashvalue;
        }
        flags = fl;
-       refcount = 0;
+       set_refcount(0);
        return *this;
 }
 
@@ -93,18 +93,8 @@ const basic & basic::operator=(const basic & other)
 //////////
 
 /** Construct object from archive_node. */
-basic::basic(const archive_node &n, lst &sym_lst) : flags(0), refcount(0)
-{
-       // Reconstruct tinfo_key from class name
-       std::string class_name;
-       if (n.find_string("class", class_name))
-               tinfo_key = find_tinfo_key(class_name);
-       else
-               throw (std::runtime_error("archive node contains no class name"));
-}
-
-/** Unarchive the object. */
-DEFAULT_UNARCHIVE(basic)
+void basic::read_archive(const archive_node& n, lst& syms)
+{ }
 
 /** Archive the object. */
 void basic::archive(archive_node &n) const
@@ -184,7 +174,7 @@ void basic::do_print(const print_context & c, unsigned level) const
 /** Tree output to stream. */
 void basic::do_print_tree(const print_tree & c, unsigned level) const
 {
-       c.s << std::string(level, ' ') << class_name()
+       c.s << std::string(level, ' ') << class_name() << " @" << this
            << std::hex << ", hash=0x" << hashvalue << ", flags=0x" << flags << std::dec;
        if (nops())
                c.s << ", nops=" << nops();
@@ -208,7 +198,7 @@ void basic::do_print_python_repr(const print_python_repr & c, unsigned level) co
  *  @see basic::dbgprinttree */
 void basic::dbgprint() const
 {
-       this->print(std::cerr);
+       this->print(print_dflt(std::cerr));
        std::cerr << std::endl;
 }
 
@@ -250,7 +240,7 @@ ex basic::op(size_t i) const
        throw(std::range_error(std::string("basic::op(): ") + class_name() + std::string(" has no operands")));
 }
 
-/** Return modifyable operand/member at position i. */
+/** Return modifiable operand/member at position i. */
 ex & basic::let_op(size_t i)
 {
        ensure_if_modifiable();
@@ -287,13 +277,13 @@ ex & basic::operator[](size_t i)
  *  the pattern itself or one of the children 'has' it.  As a consequence
  *  (according to the definition of children) given e=x+y+z, e.has(x) is true
  *  but e.has(x+y) is false. */
-bool basic::has(const ex & pattern) const
+bool basic::has(const ex & pattern, unsigned options) const
 {
-       lst repl_lst;
+       exmap repl_lst;
        if (match(pattern, repl_lst))
                return true;
        for (size_t i=0; i<nops(); i++)
-               if (op(i).has(pattern))
+               if (op(i).has(pattern, options))
                        return true;
        
        return false;
@@ -307,12 +297,29 @@ ex basic::map(map_function & f) const
        if (num == 0)
                return *this;
 
-       basic *copy = duplicate();
-       copy->setflag(status_flags::dynallocated);
-       copy->clearflag(status_flags::hash_calculated | status_flags::expanded);
-       for (size_t i=0; i<num; i++)
-               copy->let_op(i) = f(copy->op(i));
-       return *copy;
+       basic *copy = nullptr;
+       for (size_t i=0; i<num; i++) {
+               const ex & o = op(i);
+               const ex & n = f(o);
+               if (!are_ex_trivially_equal(o, n)) {
+                       if (copy == nullptr)
+                               copy = duplicate();
+                       copy->let_op(i) = n;
+               }
+       }
+
+       if (copy) {
+               copy->setflag(status_flags::dynallocated);
+               copy->clearflag(status_flags::hash_calculated | status_flags::expanded);
+               return *copy;
+       } else
+               return *this;
+}
+
+/** Check whether this is a polynomial in the given variables. */
+bool basic::is_polynomial(const ex & var) const
+{
+       return !has(var) || is_equal(ex_to<basic>(var));
 }
 
 /** Return degree of highest power in object s. */
@@ -352,56 +359,32 @@ ex basic::collect(const ex & s, bool distributed) const
 
                else if (distributed) {
 
-                       // Get lower/upper degree of all symbols in list
-                       size_t num = s.nops();
-                       struct sym_info {
-                               ex sym;
-                               int ldeg, deg;
-                               int cnt;  // current degree, 'counter'
-                               ex coeff; // coefficient for degree 'cnt'
-                       };
-                       sym_info *si = new sym_info[num];
-                       ex c = *this;
-                       for (size_t i=0; i<num; i++) {
-                               si[i].sym = s.op(i);
-                               si[i].ldeg = si[i].cnt = this->ldegree(si[i].sym);
-                               si[i].deg = this->degree(si[i].sym);
-                               c = si[i].coeff = c.coeff(si[i].sym, si[i].cnt);
-                       }
-
-                       while (true) {
-
-                               // Calculate coeff*x1^c1*...*xn^cn
-                               ex y = _ex1;
-                               for (size_t i=0; i<num; i++) {
-                                       int cnt = si[i].cnt;
-                                       y *= power(si[i].sym, cnt);
-                               }
-                               x += y * si[num - 1].coeff;
-
-                               // Increment counters
-                               size_t n = num - 1;
-                               while (true) {
-                                       ++si[n].cnt;
-                                       if (si[n].cnt <= si[n].deg) {
-                                               // Update coefficients
-                                               ex c;
-                                               if (n == 0)
-                                                       c = *this;
-                                               else
-                                                       c = si[n - 1].coeff;
-                                               for (size_t i=n; i<num; i++)
-                                                       c = si[i].coeff = c.coeff(si[i].sym, si[i].cnt);
-                                               break;
-                                       }
-                                       if (n == 0)
-                                               goto done;
-                                       si[n].cnt = si[n].ldeg;
-                                       n--;
+                       x = this->expand();
+                       if (! is_a<add>(x))
+                               return x; 
+                       const lst& l(ex_to<lst>(s));
+
+                       exmap cmap;
+                       cmap[_ex1] = _ex0;
+                       for (const_iterator xi=x.begin(); xi!=x.end(); ++xi) {
+                               ex key = _ex1;
+                               ex pre_coeff = *xi;
+                               for (lst::const_iterator li=l.begin(); li!=l.end(); ++li) {
+                                       int cexp = pre_coeff.degree(*li);
+                                       pre_coeff = pre_coeff.coeff(*li, cexp);
+                                       key *= pow(*li, cexp);
                                }
+                               exmap::iterator ci = cmap.find(key);
+                               if (ci != cmap.end())
+                                       ci->second += pre_coeff;
+                               else
+                                       cmap.insert(exmap::value_type(key, pre_coeff));
                        }
 
-done:          delete[] si;
+                       exvector resv;
+                       for (exmap::const_iterator mi=cmap.begin(); mi != cmap.end(); ++mi)
+                               resv.push_back((mi->first)*(mi->second));
+                       return (new add(resv))->setflag(status_flags::dynallocated);
 
                } else {
 
@@ -472,6 +455,20 @@ ex basic::evalm() const
                return map(map_evalm);
 }
 
+/** Function object to be applied by basic::eval_integ(). */
+struct eval_integ_map_function : public map_function {
+       ex operator()(const ex & e) { return eval_integ(e); }
+} map_eval_integ;
+
+/** Evaluate integrals, if result is known. */
+ex basic::eval_integ() const
+{
+       if (nops() == 0)
+               return *this;
+       else
+               return map(map_eval_integ);
+}
+
 /** Perform automatic symbolic evaluations on indexed expression that
  *  contains this object as the base expression. */
 ex basic::eval_indexed(const basic & i) const
@@ -486,7 +483,7 @@ ex basic::eval_indexed(const basic & i) const
  *  (or a subclass) and their indices are compatible. This function is used
  *  internally by simplify_indexed().
  *
- *  @param self First indexed expression; it's base object is *this
+ *  @param self First indexed expression; its base object is *this
  *  @param other Second indexed expression
  *  @return sum of self and other 
  *  @see ex::simplify_indexed() */
@@ -498,7 +495,7 @@ ex basic::add_indexed(const ex & self, const ex & other) const
 /** Multiply an indexed expression with a scalar. This function is used
  *  internally by simplify_indexed().
  *
- *  @param self Indexed expression; it's base object is *this
+ *  @param self Indexed expression; its base object is *this
  *  @param other Numeric value
  *  @return product of self and other
  *  @see ex::simplify_indexed() */
@@ -514,7 +511,7 @@ ex basic::scalar_mul_indexed(const ex & self, const numeric & other) const
  *  and that at least one dummy index has been found. This functions is
  *  used internally by simplify_indexed().
  *
- *  @param self Pointer to first indexed expression; it's base object is *this
+ *  @param self Pointer to first indexed expression; its base object is *this
  *  @param other Pointer to second indexed expression
  *  @param v The complete vector of factors
  *  @return true if the contraction was successful, false otherwise
@@ -526,9 +523,9 @@ bool basic::contract_with(exvector::iterator self, exvector::iterator other, exv
 }
 
 /** Check whether the expression matches a given pattern. For every wildcard
- *  object in the pattern, an expression of the form "wildcard == matching_expression"
- *  is added to repl_lst. */
-bool basic::match(const ex & pattern, lst & repl_lst) const
+ *  object in the pattern, a pair with the wildcard as a key and matching 
+ *  expression as a value is added to repl_lst. */
+bool basic::match(const ex & pattern, exmap& repl_lst) const
 {
 /*
        Sweet sweet shapes, sweet sweet shapes,
@@ -549,19 +546,19 @@ bool basic::match(const ex & pattern, lst & repl_lst) const
        if (is_exactly_a<wildcard>(pattern)) {
 
                // Wildcard matches anything, but check whether we already have found
-               // a match for that wildcard first (if so, it the earlier match must
-               // be the same expression)
-               for (lst::const_iterator it = repl_lst.begin(); it != repl_lst.end(); ++it) {
-                       if (it->op(0).is_equal(pattern))
-                               return is_equal(ex_to<basic>(it->op(1)));
+               // a match for that wildcard first (if so, the earlier match must be
+               // the same expression)
+               for (exmap::const_iterator it = repl_lst.begin(); it != repl_lst.end(); ++it) {
+                       if (it->first.is_equal(pattern))
+                               return is_equal(ex_to<basic>(it->second));
                }
-               repl_lst.append(pattern == *this);
+               repl_lst[pattern] = *this;
                return true;
 
        } else {
 
                // Expression must be of the same type as the pattern
-               if (tinfo() != ex_to<basic>(pattern).tinfo())
+               if (typeid(*this) != typeid(ex_to<basic>(pattern)))
                        return false;
 
                // Number of subexpressions must match
@@ -577,12 +574,18 @@ bool basic::match(const ex & pattern, lst & repl_lst) const
                if (!match_same_type(ex_to<basic>(pattern)))
                        return false;
 
+               // Even if the expression does not match the pattern, some of
+               // its subexpressions could match it. For example, x^5*y^(-1)
+               // does not match the pattern $0^5, but its subexpression x^5
+               // does. So, save repl_lst in order to not add bogus entries.
+               exmap tmp_repl = repl_lst;
                // Otherwise the subexpressions must match one-to-one
                for (size_t i=0; i<nops(); i++)
-                       if (!op(i).match(pattern.op(i), repl_lst))
+                       if (!op(i).match(pattern.op(i), tmp_repl))
                                return false;
 
                // Looks similar enough, match found
+               repl_lst = tmp_repl;
                return true;
        }
 }
@@ -593,14 +596,17 @@ ex basic::subs_one_level(const exmap & m, unsigned options) const
        exmap::const_iterator it;
 
        if (options & subs_options::no_pattern) {
-               it = m.find(*this);
+               ex thisex = *this;
+               it = m.find(thisex);
                if (it != m.end())
                        return it->second;
+               return thisex;
        } else {
                for (it = m.begin(); it != m.end(); ++it) {
-                       lst repl_lst;
+                       exmap repl_lst;
                        if (match(ex_to<basic>(it->first), repl_lst))
-                               return it->second.subs(repl_lst, options | subs_options::no_pattern); // avoid infinite recursion when re-substituting the wildcards
+                               return it->second.subs(repl_lst, options | subs_options::no_pattern);
+                       // avoid infinite recursion when re-substituting the wildcards
                }
        }
 
@@ -674,6 +680,21 @@ exvector basic::get_free_indices() const
        return exvector(); // return an empty exvector
 }
 
+ex basic::conjugate() const
+{
+       return *this;
+}
+
+ex basic::real_part() const
+{
+       return real_part_function(*this).hold();
+}
+
+ex basic::imag_part() const
+{
+       return imag_part_function(*this).hold();
+}
+
 ex basic::eval_ncmul(const exvector & v) const
 {
        return hold_ncmul(v);
@@ -744,9 +765,12 @@ unsigned basic::return_type() const
        return return_types::commutative;
 }
 
-unsigned basic::return_type_tinfo() const
+return_type_t basic::return_type_tinfo() const
 {
-       return tinfo();
+       return_type_t rt;
+       rt.tinfo = &typeid(*this);
+       rt.rl = 0;
+       return rt;
 }
 
 /** Compute the hash value of an object and if it makes sense to store it in
@@ -757,7 +781,7 @@ unsigned basic::return_type_tinfo() const
  *  would all end up with the same hashvalue. */
 unsigned basic::calchash() const
 {
-       unsigned v = golden_ratio_hash(tinfo());
+       unsigned v = make_hash_seed(typeid(*this));
        for (size_t i=0; i<nops(); i++) {
                v = rotate_left(v);
                v ^= this->op(i).gethash();
@@ -776,7 +800,7 @@ unsigned basic::calchash() const
 struct expand_map_function : public map_function {
        unsigned options;
        expand_map_function(unsigned o) : options(o) {}
-       ex operator()(const ex & e) { return expand(e, options); }
+       ex operator()(const ex & e) { return e.expand(options); }
 };
 
 /** Expand expression, i.e. multiply it out and return the result as a new
@@ -803,15 +827,20 @@ ex basic::expand(unsigned options) const
  *  1 greater. */
 int basic::compare(const basic & other) const
 {
+#ifdef GINAC_COMPARE_STATISTICS
+       compare_statistics.total_basic_compares++;
+#endif
        const unsigned hash_this = gethash();
        const unsigned hash_other = other.gethash();
        if (hash_this<hash_other) return -1;
        if (hash_this>hash_other) return 1;
+#ifdef GINAC_COMPARE_STATISTICS
+       compare_statistics.compare_same_hashvalue++;
+#endif
 
-       const unsigned typeid_this = tinfo();
-       const unsigned typeid_other = other.tinfo();
-       if (typeid_this==typeid_other) {
-               GINAC_ASSERT(typeid(*this)==typeid(other));
+       const std::type_info& typeid_this = typeid(*this);
+       const std::type_info& typeid_other = typeid(other);
+       if (typeid_this == typeid_other) {
 //             int cmpval = compare_same_type(other);
 //             if (cmpval!=0) {
 //                     std::cout << "hash collision, same type: " 
@@ -822,6 +851,9 @@ int basic::compare(const basic & other) const
 //                     std::cout << std::endl;
 //             }
 //             return cmpval;
+#ifdef GINAC_COMPARE_STATISTICS
+               compare_statistics.compare_same_type++;
+#endif
                return compare_same_type(other);
        } else {
 //             std::cout << "hash collision, different types: " 
@@ -830,7 +862,7 @@ int basic::compare(const basic & other) const
 //             std::cout << " and ";
 //             other.print(print_tree(std::cout));
 //             std::cout << std::endl;
-               return (typeid_this<typeid_other ? -1 : 1);
+               return (typeid_this.before(typeid_other) ? -1 : 1);
        }
 }
 
@@ -842,13 +874,20 @@ int basic::compare(const basic & other) const
  *  @see is_equal_same_type */
 bool basic::is_equal(const basic & other) const
 {
+#ifdef GINAC_COMPARE_STATISTICS
+       compare_statistics.total_basic_is_equals++;
+#endif
        if (this->gethash()!=other.gethash())
                return false;
-       if (this->tinfo()!=other.tinfo())
+#ifdef GINAC_COMPARE_STATISTICS
+       compare_statistics.is_equal_same_hashvalue++;
+#endif
+       if (typeid(*this) != typeid(other))
                return false;
        
-       GINAC_ASSERT(typeid(*this)==typeid(other));
-       
+#ifdef GINAC_COMPARE_STATISTICS
+       compare_statistics.is_equal_same_type++;
+#endif
        return is_equal_same_type(other);
 }
 
@@ -866,7 +905,7 @@ const basic & basic::hold() const
  *  is not the case. */
 void basic::ensure_if_modifiable() const
 {
-       if (refcount > 1)
+       if (get_refcount() > 1)
                throw(std::runtime_error("cannot modify multiply referenced object"));
        clearflag(status_flags::hash_calculated | status_flags::evaluated);
 }
@@ -877,4 +916,27 @@ void basic::ensure_if_modifiable() const
 
 int max_recursion_level = 1024;
 
+
+#ifdef GINAC_COMPARE_STATISTICS
+compare_statistics_t::~compare_statistics_t()
+{
+       std::clog << "ex::compare() called " << total_compares << " times" << std::endl;
+       std::clog << "nontrivial compares: " << nontrivial_compares << " times" << std::endl;
+       std::clog << "basic::compare() called " << total_basic_compares << " times" << std::endl;
+       std::clog << "same hashvalue in compare(): " << compare_same_hashvalue << " times" << std::endl;
+       std::clog << "compare_same_type() called " << compare_same_type << " times" << std::endl;
+       std::clog << std::endl;
+       std::clog << "ex::is_equal() called " << total_is_equals << " times" << std::endl;
+       std::clog << "nontrivial is_equals: " << nontrivial_is_equals << " times" << std::endl;
+       std::clog << "basic::is_equal() called " << total_basic_is_equals << " times" << std::endl;
+       std::clog << "same hashvalue in is_equal(): " << is_equal_same_hashvalue << " times" << std::endl;
+       std::clog << "is_equal_same_type() called " << is_equal_same_type << " times" << std::endl;
+       std::clog << std::endl;
+       std::clog << "basic::gethash() called " << total_gethash << " times" << std::endl;
+       std::clog << "used cached hashvalue " << gethash_cached << " times" << std::endl;
+}
+
+compare_statistics_t compare_statistics;
+#endif
+
 } // namespace GiNaC