]> www.ginac.de Git - ginac.git/blobdiff - ginac/indexed.cpp
- dummy index recognition in products was flawed: A.i.i*B.j.j would be
[ginac.git] / ginac / indexed.cpp
index ea4266cba5ac8e0c5e93d26d58e998060bd61193..255fed5322fa1ed77c319a5ab5a567574a7359c5 100644 (file)
@@ -52,11 +52,7 @@ void indexed::copy(const indexed & other)
        symmetry = other.symmetry;
 }
 
-void indexed::destroy(bool call_parent)
-{
-       if (call_parent)
-               inherited::destroy(call_parent);
-}
+DEFAULT_DESTROY(indexed)
 
 //////////
 // other constructors
@@ -66,56 +62,56 @@ indexed::indexed(const ex & b) : inherited(b), symmetry(unknown)
 {
        debugmsg("indexed constructor from ex", LOGLEVEL_CONSTRUCT);
        tinfo_key = TINFO_indexed;
-       GINAC_ASSERT(all_indices_of_type_idx());
+       assert_all_indices_of_type_idx();
 }
 
 indexed::indexed(const ex & b, const ex & i1) : inherited(b, i1), symmetry(unknown)
 {
        debugmsg("indexed constructor from ex,ex", LOGLEVEL_CONSTRUCT);
        tinfo_key = TINFO_indexed;
-       GINAC_ASSERT(all_indices_of_type_idx());
+       assert_all_indices_of_type_idx();
 }
 
 indexed::indexed(const ex & b, const ex & i1, const ex & i2) : inherited(b, i1, i2), symmetry(unknown)
 {
        debugmsg("indexed constructor from ex,ex,ex", LOGLEVEL_CONSTRUCT);
        tinfo_key = TINFO_indexed;
-       GINAC_ASSERT(all_indices_of_type_idx());
+       assert_all_indices_of_type_idx();
 }
 
 indexed::indexed(const ex & b, const ex & i1, const ex & i2, const ex & i3) : inherited(b, i1, i2, i3), symmetry(unknown)
 {
        debugmsg("indexed constructor from ex,ex,ex,ex", LOGLEVEL_CONSTRUCT);
        tinfo_key = TINFO_indexed;
-       GINAC_ASSERT(all_indices_of_type_idx());
+       assert_all_indices_of_type_idx();
 }
 
 indexed::indexed(const ex & b, const ex & i1, const ex & i2, const ex & i3, const ex & i4) : inherited(b, i1, i2, i3, i4), symmetry(unknown)
 {
        debugmsg("indexed constructor from ex,ex,ex,ex,ex", LOGLEVEL_CONSTRUCT);
        tinfo_key = TINFO_indexed;
-       GINAC_ASSERT(all_indices_of_type_idx());
+       assert_all_indices_of_type_idx();
 }
 
 indexed::indexed(const ex & b, symmetry_type symm, const ex & i1, const ex & i2) : inherited(b, i1, i2), symmetry(symm)
 {
        debugmsg("indexed constructor from ex,symmetry,ex,ex", LOGLEVEL_CONSTRUCT);
        tinfo_key = TINFO_indexed;
-       GINAC_ASSERT(all_indices_of_type_idx());
+       assert_all_indices_of_type_idx();
 }
 
 indexed::indexed(const ex & b, symmetry_type symm, const ex & i1, const ex & i2, const ex & i3) : inherited(b, i1, i2, i3), symmetry(symm)
 {
        debugmsg("indexed constructor from ex,symmetry,ex,ex,ex", LOGLEVEL_CONSTRUCT);
        tinfo_key = TINFO_indexed;
-       GINAC_ASSERT(all_indices_of_type_idx());
+       assert_all_indices_of_type_idx();
 }
 
 indexed::indexed(const ex & b, symmetry_type symm, const ex & i1, const ex & i2, const ex & i3, const ex & i4) : inherited(b, i1, i2, i3, i4), symmetry(symm)
 {
        debugmsg("indexed constructor from ex,symmetry,ex,ex,ex,ex", LOGLEVEL_CONSTRUCT);
        tinfo_key = TINFO_indexed;
-       GINAC_ASSERT(all_indices_of_type_idx());
+       assert_all_indices_of_type_idx();
 }
 
 indexed::indexed(const ex & b, const exvector & v) : inherited(b), symmetry(unknown)
@@ -123,7 +119,7 @@ indexed::indexed(const ex & b, const exvector & v) : inherited(b), symmetry(unkn
        debugmsg("indexed constructor from ex,exvector", LOGLEVEL_CONSTRUCT);
        seq.insert(seq.end(), v.begin(), v.end());
        tinfo_key = TINFO_indexed;
-       GINAC_ASSERT(all_indices_of_type_idx());
+       assert_all_indices_of_type_idx();
 }
 
 indexed::indexed(const ex & b, symmetry_type symm, const exvector & v) : inherited(b), symmetry(symm)
@@ -131,35 +127,34 @@ indexed::indexed(const ex & b, symmetry_type symm, const exvector & v) : inherit
        debugmsg("indexed constructor from ex,symmetry,exvector", LOGLEVEL_CONSTRUCT);
        seq.insert(seq.end(), v.begin(), v.end());
        tinfo_key = TINFO_indexed;
-       GINAC_ASSERT(all_indices_of_type_idx());
+       assert_all_indices_of_type_idx();
 }
 
 indexed::indexed(symmetry_type symm, const exprseq & es) : inherited(es), symmetry(symm)
 {
        debugmsg("indexed constructor from symmetry,exprseq", LOGLEVEL_CONSTRUCT);
        tinfo_key = TINFO_indexed;
-       GINAC_ASSERT(all_indices_of_type_idx());
+       assert_all_indices_of_type_idx();
 }
 
 indexed::indexed(symmetry_type symm, const exvector & v, bool discardable) : inherited(v, discardable), symmetry(symm)
 {
        debugmsg("indexed constructor from symmetry,exvector", LOGLEVEL_CONSTRUCT);
        tinfo_key = TINFO_indexed;
-       GINAC_ASSERT(all_indices_of_type_idx());
+       assert_all_indices_of_type_idx();
 }
 
 indexed::indexed(symmetry_type symm, exvector * vp) : inherited(vp), symmetry(symm)
 {
        debugmsg("indexed constructor from symmetry,exvector *", LOGLEVEL_CONSTRUCT);
        tinfo_key = TINFO_indexed;
-       GINAC_ASSERT(all_indices_of_type_idx());
+       assert_all_indices_of_type_idx();
 }
 
 //////////
 // archiving
 //////////
 
-/** Construct object from archive_node. */
 indexed::indexed(const archive_node &n, const lst &sym_lst) : inherited(n, sym_lst)
 {
        debugmsg("indexed constructor from archive_node", LOGLEVEL_CONSTRUCT);
@@ -168,19 +163,14 @@ indexed::indexed(const archive_node &n, const lst &sym_lst) : inherited(n, sym_l
                throw (std::runtime_error("unknown indexed symmetry type in archive"));
 }
 
-/** Unarchive the object. */
-ex indexed::unarchive(const archive_node &n, const lst &sym_lst)
-{
-       return (new indexed(n, sym_lst))->setflag(status_flags::dynallocated);
-}
-
-/** Archive the object. */
 void indexed::archive(archive_node &n) const
 {
        inherited::archive(n);
        n.add_unsigned("symmetry", symmetry);
 }
 
+DEFAULT_UNARCHIVE(indexed)
+
 //////////
 // functions overriding virtual functions from bases classes
 //////////
@@ -330,6 +320,20 @@ ex indexed::eval(int level) const
        if (level > 1)
                return indexed(symmetry, evalchildren(level));
 
+       const ex &base = seq[0];
+
+       // If the base object is 0, the whole object is 0
+       if (base.is_zero())
+               return _ex0();
+
+       // If the base object is a product, pull out the numeric factor
+       if (is_ex_exactly_of_type(base, mul) && is_ex_exactly_of_type(base.op(base.nops() - 1), numeric)) {
+               exvector v = seq;
+               ex f = ex_to_numeric(base.op(base.nops() - 1));
+               v[0] = seq[0] / f;
+               return f * thisexprseq(v);
+       }
+
        // Canonicalize indices according to the symmetry properties
        if (seq.size() > 2 && (symmetry != unknown && symmetry != mixed)) {
                exvector v = seq;
@@ -343,7 +347,7 @@ ex indexed::eval(int level) const
        }
 
        // Let the class of the base object perform additional evaluations
-       return op(0).bp->eval_indexed(*this);
+       return base.bp->eval_indexed(*this);
 }
 
 ex indexed::thisexprseq(const exvector & v) const
@@ -426,64 +430,21 @@ void indexed::printindices(std::ostream & os) const
 /** Check whether all indices are of class idx. This function is used
  *  internally to make sure that all constructed indexed objects really
  *  carry indices and not some other classes. */
-bool indexed::all_indices_of_type_idx(void) const
+void indexed::assert_all_indices_of_type_idx(void) const
 {
        GINAC_ASSERT(seq.size() > 0);
        exvector::const_iterator it = seq.begin() + 1, itend = seq.end();
        while (it != itend) {
                if (!is_ex_of_type(*it, idx))
-                       return false;
+                       throw(std::invalid_argument("indices of indexed object must be of type idx"));
                it++;
        }
-       return true;
 }
 
 //////////
 // global functions
 //////////
 
-/** Given a vector of indices, split them into two vectors, one containing
- *  the free indices, the other containing the dummy indices. */
-static void find_free_and_dummy(exvector::const_iterator it, exvector::const_iterator itend, exvector & out_free, exvector & out_dummy)
-{
-       out_free.clear();
-       out_dummy.clear();
-
-       // No indices? Then do nothing
-       if (it == itend)
-               return;
-
-       // Only one index? Then it is a free one if it's not numeric
-       if (itend - it == 1) {
-               if (ex_to_idx(*it).is_symbolic())
-                       out_free.push_back(*it);
-               return;
-       }
-
-       // Sort index vector. This will cause dummy indices come to lie next
-       // to each other (because the sort order is defined to guarantee this).
-       exvector v(it, itend);
-       sort_index_vector(v);
-
-       // Find dummy pairs and free indices
-       it = v.begin(); itend = v.end();
-       exvector::const_iterator last = it++;
-       while (it != itend) {
-               if (is_dummy_pair(*it, *last)) {
-                       out_dummy.push_back(*last);
-                       it++;
-                       if (it == itend)
-                               return;
-               } else {
-                       if (!it->is_equal(*last) && ex_to_idx(*last).is_symbolic())
-                               out_free.push_back(*last);
-               }
-               last = it++;
-       }
-       if (ex_to_idx(*last).is_symbolic())
-               out_free.push_back(*last);
-}
-
 /** Check whether two sorted index vectors are consistent (i.e. equal). */
 static bool indices_consistent(const exvector & v1, const exvector & v2)
 {
@@ -502,6 +463,29 @@ static bool indices_consistent(const exvector & v1, const exvector & v2)
        return true;
 }
 
+exvector indexed::get_indices(void) const
+{
+       GINAC_ASSERT(seq.size() >= 1);
+       return exvector(seq.begin() + 1, seq.end());
+}
+
+exvector indexed::get_dummy_indices(void) const
+{
+       exvector free_indices, dummy_indices;
+       find_free_and_dummy(seq.begin() + 1, seq.end(), free_indices, dummy_indices);
+       return dummy_indices;
+}
+
+exvector indexed::get_dummy_indices(const indexed & other) const
+{
+       exvector indices = get_free_indices();
+       exvector other_indices = other.get_free_indices();
+       indices.insert(indices.end(), other_indices.begin(), other_indices.end());
+       exvector dummy_indices;
+       find_dummy_indices(indices, dummy_indices);
+       return dummy_indices;
+}
+
 exvector indexed::get_free_indices(void) const
 {
        exvector free_indices, dummy_indices;
@@ -535,7 +519,7 @@ exvector mul::get_free_indices(void) const
 
        // And remove the dummy indices
        exvector free_indices, dummy_indices;
-       find_free_and_dummy(un.begin(), un.end(), free_indices, dummy_indices);
+       find_free_and_dummy(un, free_indices, dummy_indices);
        return free_indices;
 }
 
@@ -550,7 +534,7 @@ exvector ncmul::get_free_indices(void) const
 
        // And remove the dummy indices
        exvector free_indices, dummy_indices;
-       find_free_and_dummy(un.begin(), un.end(), free_indices, dummy_indices);
+       find_free_and_dummy(un, free_indices, dummy_indices);
        return free_indices;
 }
 
@@ -586,7 +570,7 @@ ex simplify_indexed_product(const ex & e, exvector & free_indices, const scalar_
                        } else if (is_ex_exactly_of_type(f, ncmul)) {
                                // Noncommutative factor found, split it as well
                                non_commutative = true; // everything becomes noncommutative, ncmul will sort out the commutative factors later
-                               for (int j=0; j<f.nops(); i++)
+                               for (int j=0; j<f.nops(); j++)
                                        v.push_back(f.op(j));
                        } else
                                v.push_back(f);
@@ -603,18 +587,26 @@ try_again:
                if (!is_ex_of_type(*it1, indexed))
                        continue;
 
-               // Indexed factor found, look for contraction candidates
+               // Indexed factor found, get free indices and look for contraction
+               // candidates
+               exvector free1, dummy1;
+               find_free_and_dummy(ex_to_indexed(*it1).seq.begin() + 1, ex_to_indexed(*it1).seq.end(), free1, dummy1);
+
                exvector::iterator it2;
                for (it2 = it1 + 1; it2 != itend; it2++) {
 
                        if (!is_ex_of_type(*it2, indexed))
                                continue;
 
+                       // Find free indices of second factor and merge them with free
+                       // indices of first factor
+                       exvector un;
+                       find_free_and_dummy(ex_to_indexed(*it2).seq.begin() + 1, ex_to_indexed(*it2).seq.end(), un, dummy1);
+                       un.insert(un.end(), free1.begin(), free1.end());
+
                        // Check whether the two factors share dummy indices
-                       exvector un(ex_to_indexed(*it1).seq.begin() + 1, ex_to_indexed(*it1).seq.end());
-                       un.insert(un.end(), ex_to_indexed(*it2).seq.begin() + 1, ex_to_indexed(*it2).seq.end());
                        exvector free, dummy;
-                       find_free_and_dummy(un.begin(), un.end(), free, dummy);
+                       find_free_and_dummy(un, free, dummy);
                        if (dummy.size() == 0)
                                continue;
 
@@ -628,13 +620,23 @@ try_again:
                                }
                        }
 
+                       // Contraction of symmetric with antisymmetric object is zero
+                       if ((ex_to_indexed(*it1).symmetry == indexed::symmetric &&
+                            ex_to_indexed(*it2).symmetry == indexed::antisymmetric
+                         || ex_to_indexed(*it1).symmetry == indexed::antisymmetric &&
+                            ex_to_indexed(*it2).symmetry == indexed::symmetric)
+                        && dummy.size() > 1) {
+                               free_indices.clear();
+                               return _ex0();
+                       }
+
                        // Try to contract the first one with the second one
-                       bool contracted = it1->op(0).bp->contract_with(*it1, *it2);
+                       bool contracted = it1->op(0).bp->contract_with(it1, it2, v);
                        if (!contracted) {
 
                                // That didn't work; maybe the second object knows how to
                                // contract itself with the first one
-                               contracted = it2->op(0).bp->contract_with(*it2, *it1);
+                               contracted = it2->op(0).bp->contract_with(it2, it1, v);
                        }
                        if (contracted) {
                                something_changed = true;
@@ -657,15 +659,23 @@ try_again:
                }
                it1++;
        }
-       find_free_and_dummy(un.begin(), un.end(), free_indices, dummy_indices);
+       find_free_and_dummy(un, free_indices, dummy_indices);
 
+       ex r;
        if (something_changed) {
                if (non_commutative)
-                       return ncmul(v);
+                       r = ncmul(v);
                else
-                       return mul(v);
+                       r = mul(v);
        } else
-               return e;
+               r = e;
+
+       // Product of indexed object with a scalar?
+       if (is_ex_exactly_of_type(r, mul) && r.nops() == 2
+        && is_ex_exactly_of_type(r.op(1), numeric) && is_ex_of_type(r.op(0), indexed))
+               return r.op(0).op(0).bp->scalar_mul_indexed(r.op(0), ex_to_numeric(r.op(1)));
+       else
+               return r;
 }
 
 /** Simplify indexed expression, return list of free indices. */
@@ -685,15 +695,27 @@ ex simplify_indexed(const ex & e, exvector & free_indices, const scalar_products
        // Simplification of sum = sum of simplifications, check consistency of
        // free indices in each term
        if (is_ex_exactly_of_type(e_expanded, add)) {
+               bool first = true;
                ex sum = _ex0();
+               free_indices.clear();
 
                for (unsigned i=0; i<e_expanded.nops(); i++) {
                        exvector free_indices_of_term;
-                       sum += simplify_indexed(e_expanded.op(i), free_indices_of_term, sp);
-                       if (i == 0)
-                               free_indices = free_indices_of_term;
-                       else if (!indices_consistent(free_indices, free_indices_of_term))
-                               throw (std::runtime_error("simplify_indexed: inconsistent indices in sum"));
+                       ex term = simplify_indexed(e_expanded.op(i), free_indices_of_term, sp);
+                       if (!term.is_zero()) {
+                               if (first) {
+                                       free_indices = free_indices_of_term;
+                                       sum = term;
+                                       first = false;
+                               } else {
+                                       if (!indices_consistent(free_indices, free_indices_of_term))
+                                               throw (std::runtime_error("simplify_indexed: inconsistent indices in sum"));
+                                       if (is_ex_of_type(sum, indexed) && is_ex_of_type(term, indexed))
+                                               sum = sum.op(0).bp->add_indexed(sum, term);
+                                       else
+                                               sum += term;
+                               }
+                       }
                }
 
                return sum;