sums of indexed matrices are now possible

[ginac.git] / ginac / indexed.cpp

diff --git a/ginac/indexed.cpp b/ginac/indexed.cpp
index c3fe1d9a26e6d49ca311b0e793913d6050ef402f..e23709d5f506647280eca2f54fb528f807a5dc8f 100644 (file)
--- a/ginac/indexed.cpp
+++ b/ginac/indexed.cpp
@@ -66,56 +66,56 @@ 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 +123,7 @@ 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)
@@ -131,28 +131,28 @@ 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();
 }
 
 //////////
@@ -330,6 +330,20 @@ 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 +357,7 @@ 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
@@ -426,16 +440,15 @@ 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;
 }
 
 //////////
@@ -502,6 +515,13 @@ static bool indices_consistent(const exvector & v1, const exvector & v2)
        return true;
 }
 
+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_free_indices(void) const
 {
        exvector free_indices, dummy_indices;
@@ -685,15 +705,17 @@ 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)) {
-               ex sum = _ex0();
+               ex sum = simplify_indexed(e_expanded.op(0), free_indices, sp);
 
-               for (unsigned i=0; i<e_expanded.nops(); i++) {
+               for (unsigned i=1; 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))
+                       ex term = simplify_indexed(e_expanded.op(i), free_indices_of_term, sp);
+                       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;