- fixed three little standard-conformance issues.

[ginac.git] / ginac / symmetry.cpp

diff --git a/ginac/symmetry.cpp b/ginac/symmetry.cpp
index ab31838b18668d156cc751930579463796666948..2312526e67a367df028a1ec1e68f2053f5e4961a 100644 (file)
--- a/ginac/symmetry.cpp
+++ b/ginac/symmetry.cpp
@@ -24,9 +24,6 @@
 #include <functional>
 #include <algorithm>
 
-#define DO_GINAC_ASSERT
-#include "assertion.h"
-
 #include "symmetry.h"
 #include "lst.h"
 #include "numeric.h" // for factorial()
@@ -39,6 +36,20 @@ 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
 //////////
@@ -138,41 +149,77 @@ 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));
-       const symmetry &o = static_cast<const 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 (children.empty()) {
-               if (indices.size() > 0)
-                       c.s << *(indices.begin());
-       } else {
+       if (is_of_type(c, print_tree)) {
+
+               c.s << std::string(level, ' ') << class_name()
+                   << std::hex << ", hash=0x" << hashvalue << ", flags=0x" << flags << std::dec
+                   << ", type=";
+
                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 << '(';
-               for (unsigned i=0; i<children.size(); i++) {
-                       children[i].print(c);
-                       if (i != children.size() - 1)
-                               c.s << ",";
+
+               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;
+               }
+
+       } 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 << ')';
        }
 }
 
@@ -265,8 +312,8 @@ public:
 
 int canonicalize(exvector::iterator v, const symmetry &symm)
 {
-       // No children? Then do nothing
-       if (symm.children.empty())
+       // Less than two indices? Then do nothing
+       if (symm.indices.size() < 2)
                return INT_MAX;
 
        // Canonicalize children first
@@ -289,12 +336,15 @@ int canonicalize(exvector::iterator v, const symmetry &symm)
        first = symm.children.begin();
        switch (symm.type) {
                case symmetry::symmetric:
+                       // Sort the children in ascending order
                        shaker_sort(first, last, sy_is_less(v), sy_swap(v, something_changed));
                        break;
                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));
                        break;
                case symmetry::cyclic:
+                       // Permute the smallest child to the front
                        cyclic_permutation(first, last, min_element(first, last, sy_is_less(v)), sy_swap(v, something_changed));
                        break;
                default:
@@ -308,7 +358,7 @@ int canonicalize(exvector::iterator v, const symmetry &symm)
 static ex symm(const ex & e, exvector::const_iterator first, exvector::const_iterator last, bool asymmetric)
 {
        // Need at least 2 objects for this operation
-       int num = last - first;
+       unsigned num = last - first;
        if (num < 2)
                return e;
 
@@ -357,7 +407,7 @@ ex antisymmetrize(const ex & e, exvector::const_iterator first, exvector::const_
 ex symmetrize_cyclic(const ex & e, exvector::const_iterator first, exvector::const_iterator last)
 {
        // Need at least 2 objects for this operation
-       int num = last - first;
+       unsigned num = last - first;
        if (num < 2)
                return e;