- prepared for 1.0.13 release
[ginac.git] / ginac / symmetry.cpp
index dc2546ff907f52a1222a23863177a66d48a922d7..536d1cd5115c31edf125ce83693afdd4792dd667 100644 (file)
@@ -3,7 +3,7 @@
  *  Implementation of GiNaC's symmetry definitions. */
 
 /*
- *  GiNaC Copyright (C) 1999-2001 Johannes Gutenberg University Mainz, Germany
+ *  GiNaC Copyright (C) 1999-2003 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
@@ -20,9 +20,9 @@
  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */
 
+#include <iostream>
 #include <stdexcept>
 #include <functional>
-#include <algorithm>
 
 #include "symmetry.h"
 #include "lst.h"
 #include "print.h"
 #include "archive.h"
 #include "utils.h"
-#include "debugmsg.h"
 
 namespace GiNaC {
 
 GINAC_IMPLEMENT_REGISTERED_CLASS(symmetry, basic)
 
+/*
+   Some notes about the structure of a symmetry tree:
+    - The leaf nodes of the tree are of type "none", have one index, and no
+      children (of course). They are constructed by the symmetry(unsigned)
+      constructor.
+    - Leaf nodes are the only nodes that only have one index.
+    - Container nodes contain two or more children. The "indices" set member
+      is the set union of the index sets of all children, and the "children"
+      vector stores the children themselves.
+    - The index set of each child of a "symm", "anti" or "cycl" node must
+      have the same size. It follows that the children of such a node are
+      either all leaf nodes, or all container nodes with two or more indices.
+*/
+
 //////////
-// default constructor, destructor, copy constructor assignment operator and helpers
+// default ctor, dtor, copy ctor, assignment operator and helpers
 //////////
 
 symmetry::symmetry() : type(none)
 {
-       debugmsg("symmetry default constructor", LOGLEVEL_CONSTRUCT);
        tinfo_key = TINFO_symmetry;
 }
 
@@ -62,14 +74,12 @@ DEFAULT_DESTROY(symmetry)
 
 symmetry::symmetry(unsigned i) : type(none)
 {
-       debugmsg("symmetry constructor from unsigned", LOGLEVEL_CONSTRUCT);
        indices.insert(i);
        tinfo_key = TINFO_symmetry;
 }
 
 symmetry::symmetry(symmetry_type t, const symmetry &c1, const symmetry &c2) : type(t)
 {
-       debugmsg("symmetry constructor from symmetry_type,symmetry &,symmetry &", LOGLEVEL_CONSTRUCT);
        add(c1); add(c2);
        tinfo_key = TINFO_symmetry;
 }
@@ -81,8 +91,6 @@ symmetry::symmetry(symmetry_type t, const symmetry &c1, const symmetry &c2) : ty
 /** Construct object from archive_node. */
 symmetry::symmetry(const archive_node &n, const lst &sym_lst) : inherited(n, sym_lst)
 {
-       debugmsg("symmetry ctor from archive_node", LOGLEVEL_CONSTRUCT);
-
        unsigned t;
        if (!(n.find_unsigned("type", t)))
                throw (std::runtime_error("unknown symmetry type in archive"));
@@ -135,41 +143,75 @@ void symmetry::archive(archive_node &n) const
 DEFAULT_UNARCHIVE(symmetry)
 
 //////////
-// functions overriding virtual functions from bases classes
+// functions overriding virtual functions from base classes
 //////////
 
 int symmetry::compare_same_type(const basic & other) const
 {
-       GINAC_ASSERT(is_of_type(other, symmetry));
+       GINAC_ASSERT(is_a<symmetry>(other));
 
        // All symmetry trees are equal. They are not supposed to appear in
        // ordinary expressions anyway...
        return 0;
 }
 
-void symmetry::print(const print_context & c, unsigned level = 0) const
+void symmetry::print(const print_context & c, unsigned level) const
 {
-       debugmsg("symmetry print", LOGLEVEL_PRINT);
+       if (is_a<print_tree>(c)) {
+
+               c.s << std::string(level, ' ') << class_name()
+                   << std::hex << ", hash=0x" << hashvalue << ", flags=0x" << flags << std::dec
+                   << ", type=";
 
-       if (children.empty()) {
-               if (indices.size() > 0)
-                       c.s << *(indices.begin());
-       } else {
                switch (type) {
-                       case none: c.s << '!'; break;
-                       case symmetric: c.s << '+'; break;
-                       case antisymmetric: c.s << '-'; break;
-                       case cyclic: c.s << '@'; break;
-                       default: c.s << '?'; break;
+                       case none: c.s << "none"; break;
+                       case symmetric: c.s << "symm"; break;
+                       case antisymmetric: c.s << "anti"; break;
+                       case cyclic: c.s << "cycl"; break;
+                       default: c.s << "<unknown>"; break;
+               }
+
+               c.s << ", indices=(";
+               if (!indices.empty()) {
+                       std::set<unsigned>::const_iterator i = indices.begin(), end = indices.end();
+                       --end;
+                       while (i != end)
+                               c.s << *i++ << ",";
+                       c.s << *i;
+               }
+               c.s << ")\n";
+
+               unsigned delta_indent = static_cast<const print_tree &>(c).delta_indent;
+               exvector::const_iterator i = children.begin(), end = children.end();
+               while (i != end) {
+                       i->print(c, level + delta_indent);
+                       ++i;
                }
-               c.s << '(';
-               unsigned num = children.size();
-               for (unsigned i=0; i<num; i++) {
-                       children[i].print(c);
-                       if (i != num - 1)
-                               c.s << ",";
+
+       } else {
+
+               if (children.empty()) {
+                       if (indices.size() > 0)
+                               c.s << *(indices.begin());
+                       else
+                               c.s << "none";
+               } else {
+                       switch (type) {
+                               case none: c.s << '!'; break;
+                               case symmetric: c.s << '+'; break;
+                               case antisymmetric: c.s << '-'; break;
+                               case cyclic: c.s << '@'; break;
+                               default: c.s << '?'; break;
+                       }
+                       c.s << '(';
+                       unsigned num = children.size();
+                       for (unsigned i=0; i<num; i++) {
+                               children[i].print(c);
+                               if (i != num - 1)
+                                       c.s << ",";
+                       }
+                       c.s << ')';
                }
-               c.s << ')';
        }
 }
 
@@ -181,7 +223,7 @@ symmetry &symmetry::add(const symmetry &c)
 {
        // All children must have the same number of indices
        if (type != none && !children.empty()) {
-               GINAC_ASSERT(is_ex_exactly_of_type(children[0], symmetry));
+               GINAC_ASSERT(is_exactly_a<symmetry>(children[0]));
                if (ex_to<symmetry>(children[0]).indices.size() != c.indices.size())
                        throw (std::logic_error("symmetry:add(): children must have same number of indices"));
        }
@@ -222,8 +264,8 @@ public:
 
        bool operator() (const ex &lh, const ex &rh) const
        {
-               GINAC_ASSERT(is_ex_exactly_of_type(lh, symmetry));
-               GINAC_ASSERT(is_ex_exactly_of_type(rh, symmetry));
+               GINAC_ASSERT(is_exactly_a<symmetry>(lh));
+               GINAC_ASSERT(is_exactly_a<symmetry>(rh));
                GINAC_ASSERT(ex_to<symmetry>(lh).indices.size() == ex_to<symmetry>(rh).indices.size());
                std::set<unsigned>::const_iterator ait = ex_to<symmetry>(lh).indices.begin(), aitend = ex_to<symmetry>(lh).indices.end(), bit = ex_to<symmetry>(rh).indices.begin();
                while (ait != aitend) {
@@ -248,8 +290,8 @@ public:
 
        void operator() (const ex &lh, const ex &rh)
        {
-               GINAC_ASSERT(is_ex_exactly_of_type(lh, symmetry));
-               GINAC_ASSERT(is_ex_exactly_of_type(rh, symmetry));
+               GINAC_ASSERT(is_exactly_a<symmetry>(lh));
+               GINAC_ASSERT(is_exactly_a<symmetry>(rh));
                GINAC_ASSERT(ex_to<symmetry>(lh).indices.size() == ex_to<symmetry>(rh).indices.size());
                std::set<unsigned>::const_iterator ait = ex_to<symmetry>(lh).indices.begin(), aitend = ex_to<symmetry>(lh).indices.end(), bit = ex_to<symmetry>(rh).indices.begin();
                while (ait != aitend) {
@@ -262,8 +304,8 @@ public:
 
 int canonicalize(exvector::iterator v, const symmetry &symm)
 {
-       // No children? Then do nothing
-       if (symm.children.empty())
+       // Less than two elements? Then do nothing
+       if (symm.indices.size() < 2)
                return INT_MAX;
 
        // Canonicalize children first
@@ -271,7 +313,7 @@ int canonicalize(exvector::iterator v, const symmetry &symm)
        int sign = 1;
        exvector::const_iterator first = symm.children.begin(), last = symm.children.end();
        while (first != last) {
-               GINAC_ASSERT(is_ex_exactly_of_type(*first, symmetry));
+               GINAC_ASSERT(is_exactly_a<symmetry>(*first));
                int child_sign = canonicalize(v, ex_to<symmetry>(*first));
                if (child_sign == 0)
                        return 0;
@@ -292,6 +334,8 @@ int canonicalize(exvector::iterator v, const symmetry &symm)
                case symmetry::antisymmetric:
                        // Sort the children in ascending order, keeping track of the signum
                        sign *= permutation_sign(first, last, sy_is_less(v), sy_swap(v, something_changed));
+                       if (sign == 0)
+                               return 0;
                        break;
                case symmetry::cyclic:
                        // Permute the smallest child to the front