X-Git-Url: https://www.ginac.de/ginac.git//ginac.git?p=ginac.git;a=blobdiff_plain;f=ginac%2Findexed.cpp;h=90e3d4c361b049ab016483c074c48f8b13658189;hp=86fe6115d9b8863819c44e3a393d9c99cd0b01d4;hb=31cb2d34d010ff711ad8e29787e295abdd497c75;hpb=08d556dc3ac3fbf2b0ad3acd37016a1f925d7c02 diff --git a/ginac/indexed.cpp b/ginac/indexed.cpp index 86fe6115..90e3d4c3 100644 --- a/ginac/indexed.cpp +++ b/ginac/indexed.cpp @@ -21,6 +21,7 @@ */ #include +#include #include "indexed.h" #include "idx.h" @@ -28,6 +29,9 @@ #include "mul.h" #include "ncmul.h" #include "power.h" +#include "lst.h" +#include "inifcns.h" // for symmetrize() +#include "print.h" #include "archive.h" #include "utils.h" #include "debugmsg.h" @@ -52,11 +56,7 @@ 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 @@ -159,7 +159,6 @@ indexed::indexed(symmetry_type symm, exvector * vp) : inherited(vp), symmetry(sy // 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); @@ -168,59 +167,56 @@ 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 ////////// -void indexed::printraw(std::ostream & os) const +void indexed::print(const print_context & c, unsigned level) const { - debugmsg("indexed printraw", LOGLEVEL_PRINT); + debugmsg("indexed print", LOGLEVEL_PRINT); GINAC_ASSERT(seq.size() > 0); - os << class_name() << "("; - seq[0].printraw(os); - os << ",indices="; - printrawindices(os); - os << ",hash=" << hashvalue << ",flags=" << flags << ")"; -} + if (is_of_type(c, print_tree)) { -void indexed::printtree(std::ostream & os, unsigned indent) const -{ - debugmsg("indexed printtree", LOGLEVEL_PRINT); - GINAC_ASSERT(seq.size() > 0); - - os << std::string(indent, ' ') << class_name() << ", " << seq.size()-1 << " indices"; - os << ",hash=" << hashvalue << ",flags=" << flags << std::endl; - printtreeindices(os, indent); -} + c.s << std::string(level, ' ') << class_name() + << std::hex << ", hash=0x" << hashvalue << ", flags=0x" << flags << std::dec + << ", " << seq.size()-1 << " indices"; + switch (symmetry) { + case symmetric: c.s << ", symmetric"; break; + case antisymmetric: c.s << ", antisymmetric"; break; + default: break; + } + c.s << std::endl; + unsigned delta_indent = static_cast(c).delta_indent; + seq[0].print(c, level + delta_indent); + printindices(c, level + delta_indent); -void indexed::print(std::ostream & os, unsigned upper_precedence) const -{ - debugmsg("indexed print", LOGLEVEL_PRINT); - GINAC_ASSERT(seq.size() > 0); + } else { - const ex & base = seq[0]; - bool need_parens = is_ex_exactly_of_type(base, add) || is_ex_exactly_of_type(base, mul) - || is_ex_exactly_of_type(base, ncmul) || is_ex_exactly_of_type(base, power); - if (need_parens) - os << "("; - os << base; - if (need_parens) - os << ")"; - printindices(os); + bool is_tex = is_of_type(c, print_latex); + const ex & base = seq[0]; + bool need_parens = is_ex_exactly_of_type(base, add) || is_ex_exactly_of_type(base, mul) + || is_ex_exactly_of_type(base, ncmul) || is_ex_exactly_of_type(base, power) + || is_ex_of_type(base, indexed); + if (is_tex) + c.s << "{"; + if (need_parens) + c.s << "("; + base.print(c); + if (need_parens) + c.s << ")"; + if (is_tex) + c.s << "}"; + printindices(c, level); + } } bool indexed::info(unsigned inf) const @@ -230,6 +226,12 @@ bool indexed::info(unsigned inf) const return inherited::info(inf); } +struct idx_is_not : public std::binary_function { + bool operator() (const ex & e, unsigned inf) const { + return !(ex_to_idx(e).get_value().info(inf)); + } +}; + bool indexed::all_index_values_are(unsigned inf) const { // No indices? Then no property can be fulfilled @@ -237,14 +239,7 @@ bool indexed::all_index_values_are(unsigned inf) const return false; // Check all indices - exvector::const_iterator it = seq.begin() + 1, itend = seq.end(); - while (it != itend) { - GINAC_ASSERT(is_ex_of_type(*it, idx)); - if (!ex_to_idx(*it).get_value().info(inf)) - return false; - it++; - } - return true; + return find_if(seq.begin() + 1, seq.end(), bind2nd(idx_is_not(), inf)) == seq.end(); } int indexed::compare_same_type(const basic & other) const @@ -259,31 +254,6 @@ int indexed::compare_same_type(const basic & other) const // reorder index pairs with known symmetry properties, while sort_index_vector() // always sorts the whole vector. -/** Bring a vector of indices into a canonic order (don't care about the - * symmetry of the objects carrying the indices). Dummy indices will lie - * next to each other after the sorting. - * - * @param v Index vector to be sorted */ -static void sort_index_vector(exvector &v) -{ - // Nothing to sort if less than 2 elements - if (v.size() < 2) - return; - - // Simple bubble sort algorithm should be sufficient for the small - // number of indices expected - exvector::iterator it1 = v.begin(), itend = v.end(), next_to_last_idx = itend - 1; - while (it1 != next_to_last_idx) { - exvector::iterator it2 = it1 + 1; - while (it2 != itend) { - if (it1->compare(*it2) > 0) - it1->swap(*it2); - it2++; - } - it1++; - } -} - /** Bring a vector of indices into a canonic order. This operation only makes * sense if the object carrying these indices is either symmetric or totally * antisymmetric with respect to the indices. @@ -338,15 +308,15 @@ ex indexed::eval(int level) const // 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; + 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; + if (seq.size() > 2 && (symmetry == symmetric || symmetry == antisymmetric)) { + exvector v(seq); int sig = canonicalize_indices(v.begin() + 1, v.end(), symmetry == antisymmetric); if (sig != INT_MAX) { // Something has changed while sorting indices, more evaluations later @@ -360,6 +330,24 @@ ex indexed::eval(int level) const return base.bp->eval_indexed(*this); } +int indexed::degree(const ex & s) const +{ + return is_equal(*s.bp) ? 1 : 0; +} + +int indexed::ldegree(const ex & s) const +{ + return is_equal(*s.bp) ? 1 : 0; +} + +ex indexed::coeff(const ex & s, int n) const +{ + if (is_equal(*s.bp)) + return n==1 ? _ex1() : _ex0(); + else + return n==0 ? ex(*this) : _ex0(); +} + ex indexed::thisexprseq(const exvector & v) const { return indexed(symmetry, v); @@ -400,39 +388,43 @@ ex indexed::expand(unsigned options) const // non-virtual functions in this class ////////// -void indexed::printrawindices(std::ostream & os) const +void indexed::printindices(const print_context & c, unsigned level) const { if (seq.size() > 1) { - exvector::const_iterator it=seq.begin() + 1, itend = seq.end(); - while (it != itend) { - it->printraw(os); - it++; - if (it != itend) - os << ","; - } - } -} -void indexed::printtreeindices(std::ostream & os, unsigned indent) const -{ - if (seq.size() > 1) { exvector::const_iterator it=seq.begin() + 1, itend = seq.end(); - while (it != itend) { - os << std::string(indent + delta_indent, ' '); - it->printraw(os); - os << std::endl; - it++; - } - } -} -void indexed::printindices(std::ostream & os) const -{ - if (seq.size() > 1) { - exvector::const_iterator it=seq.begin() + 1, itend = seq.end(); - while (it != itend) { - it->print(os); - it++; + if (is_of_type(c, print_latex)) { + + // TeX output: group by variance + bool first = true; + bool covariant = true; + + while (it != itend) { + bool cur_covariant = (is_ex_of_type(*it, varidx) ? ex_to_varidx(*it).is_covariant() : true); + if (first || cur_covariant != covariant) { + if (!first) + c.s << "}"; + covariant = cur_covariant; + if (covariant) + c.s << "_{"; + else + c.s << "^{"; + } + it->print(c, level); + c.s << " "; + first = false; + it++; + } + c.s << "}"; + + } else { + + // Ordinary output + while (it != itend) { + it->print(c, level); + it++; + } } } } @@ -455,48 +447,6 @@ void indexed::assert_all_indices_of_type_idx(void) const // 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) { @@ -504,15 +454,13 @@ static bool indices_consistent(const exvector & v1, const exvector & v2) if (v1.size() != v2.size()) return false; - // And also the indices themselves - exvector::const_iterator ait = v1.begin(), aitend = v1.end(), - bit = v2.begin(), bitend = v2.end(); - while (ait != aitend) { - if (!ait->is_equal(*bit)) - return false; - ait++; bit++; - } - return true; + return equal(v1.begin(), v1.end(), v2.begin(), ex_is_equal()); +} + +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 @@ -522,6 +470,27 @@ exvector indexed::get_dummy_indices(void) const 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; +} + +bool indexed::has_dummy_index_for(const ex & i) const +{ + exvector::const_iterator it = seq.begin() + 1, itend = seq.end(); + while (it != itend) { + if (is_dummy_pair(*it, i)) + return true; + it++; + } + return false; +} + exvector indexed::get_free_indices(void) const { exvector free_indices, dummy_indices; @@ -555,7 +524,7 @@ 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; } @@ -570,7 +539,7 @@ 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; } @@ -580,9 +549,61 @@ exvector power::get_free_indices(void) const return basis.get_free_indices(); } +/** Rename dummy indices in an expression. + * + * @param e Expression to be worked on + * @param local_dummy_indices The set of dummy indices that appear in the + * expression "e" + * @param global_dummy_indices The set of dummy indices that have appeared + * before and which we would like to use in "e", too. This gets updated + * by the function */ +static ex rename_dummy_indices(const ex & e, exvector & global_dummy_indices, exvector & local_dummy_indices) +{ + int global_size = global_dummy_indices.size(), + local_size = local_dummy_indices.size(); + + // Any local dummy indices at all? + if (local_size == 0) + return e; + + if (global_size < local_size) { + + // More local indices than we encountered before, add the new ones + // to the global set + int remaining = local_size - global_size; + exvector::const_iterator it = local_dummy_indices.begin(), itend = local_dummy_indices.end(); + while (it != itend && remaining > 0) { + if (find_if(global_dummy_indices.begin(), global_dummy_indices.end(), bind2nd(ex_is_equal(), *it)) == global_dummy_indices.end()) { + global_dummy_indices.push_back(*it); + global_size++; + remaining--; + } + it++; + } + } + + // Replace index symbols in expression + GINAC_ASSERT(local_size <= global_size); + bool all_equal = true; + lst local_syms, global_syms; + for (unsigned i=0; ireturn_type() != return_types::commutative); + + // 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; + bool second_noncommutative = (it2->return_type() != return_types::commutative); + + // 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; // At least one dummy index, is it a defined scalar product? + bool contracted = false; if (free.size() == 0) { if (sp.is_defined(*it1, *it2)) { *it1 = sp.evaluate(*it1, *it2); *it2 = _ex1(); - something_changed = true; - goto try_again; + goto contraction_done; } } + // 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, v); + contracted = it1->op(0).bp->contract_with(it1, it2, v); if (!contracted) { // That didn't work; maybe the second object knows how to @@ -657,37 +700,58 @@ try_again: contracted = it2->op(0).bp->contract_with(it2, it1, v); } if (contracted) { - something_changed = true; +contraction_done: + if (first_noncommutative || second_noncommutative + || is_ex_exactly_of_type(*it1, add) || is_ex_exactly_of_type(*it2, add) + || is_ex_exactly_of_type(*it1, mul) || is_ex_exactly_of_type(*it2, mul) + || is_ex_exactly_of_type(*it1, ncmul) || is_ex_exactly_of_type(*it2, ncmul)) { + + // One of the factors became a sum or product: + // re-expand expression and run again + // Non-commutative products are always re-expanded to give + // simplify_ncmul() the chance to re-order and canonicalize + // the product + ex r = (non_commutative ? ex(ncmul(v, true)) : ex(mul(v))); + return simplify_indexed(r, free_indices, dummy_indices, sp); + } // Both objects may have new indices now or they might // even not be indexed objects any more, so we have to // start over + something_changed = true; goto try_again; } } } // Find free indices (concatenate them all and call find_free_and_dummy()) - exvector un, dummy_indices; + // and all dummy indices that appear + exvector un, individual_dummy_indices; it1 = v.begin(); itend = v.end(); while (it1 != itend) { + exvector free_indices_of_factor; if (is_ex_of_type(*it1, indexed)) { - const indexed & o = ex_to_indexed(*it1); - un.insert(un.end(), o.seq.begin() + 1, o.seq.end()); - } + exvector dummy_indices_of_factor; + find_free_and_dummy(ex_to_indexed(*it1).seq.begin() + 1, ex_to_indexed(*it1).seq.end(), free_indices_of_factor, dummy_indices_of_factor); + individual_dummy_indices.insert(individual_dummy_indices.end(), dummy_indices_of_factor.begin(), dummy_indices_of_factor.end()); + } else + free_indices_of_factor = it1->get_free_indices(); + un.insert(un.end(), free_indices_of_factor.begin(), free_indices_of_factor.end()); it1++; } - find_free_and_dummy(un.begin(), un.end(), free_indices, dummy_indices); + exvector local_dummy_indices; + find_free_and_dummy(un, free_indices, local_dummy_indices); + local_dummy_indices.insert(local_dummy_indices.end(), individual_dummy_indices.begin(), individual_dummy_indices.end()); ex r; - if (something_changed) { - if (non_commutative) - r = ncmul(v); - else - r = mul(v); - } else + if (something_changed) + r = non_commutative ? ex(ncmul(v, true)) : ex(mul(v)); + else r = e; + // Dummy index renaming + r = rename_dummy_indices(r, dummy_indices, local_dummy_indices); + // 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)) @@ -697,33 +761,44 @@ try_again: } /** Simplify indexed expression, return list of free indices. */ -ex simplify_indexed(const ex & e, exvector & free_indices, const scalar_products & sp) +ex simplify_indexed(const ex & e, exvector & free_indices, exvector & dummy_indices, const scalar_products & sp) { // Expand the expression ex e_expanded = e.expand(); // Simplification of single indexed object: just find the free indices + // and perform dummy index renaming if (is_ex_of_type(e_expanded, indexed)) { const indexed &i = ex_to_indexed(e_expanded); - exvector dummy_indices; - find_free_and_dummy(i.seq.begin() + 1, i.seq.end(), free_indices, dummy_indices); - return e_expanded; + exvector local_dummy_indices; + find_free_and_dummy(i.seq.begin() + 1, i.seq.end(), free_indices, local_dummy_indices); + return rename_dummy_indices(e_expanded, dummy_indices, local_dummy_indices); } // 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 = simplify_indexed(e_expanded.op(0), free_indices, sp); + bool first = true; + ex sum = _ex0(); + free_indices.clear(); - for (unsigned i=1; iadd_indexed(sum, term); - else - sum += term; + ex term = simplify_indexed(e_expanded.op(i), free_indices_of_term, dummy_indices, 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; @@ -733,24 +808,48 @@ ex simplify_indexed(const ex & e, exvector & free_indices, const scalar_products if (is_ex_exactly_of_type(e_expanded, mul) || is_ex_exactly_of_type(e_expanded, ncmul) || (is_ex_exactly_of_type(e_expanded, power) && is_ex_of_type(e_expanded.op(0), indexed) && e_expanded.op(1).is_equal(_ex2()))) - return simplify_indexed_product(e_expanded, free_indices, sp); + return simplify_indexed_product(e_expanded, free_indices, dummy_indices, sp); // Cannot do anything free_indices.clear(); return e_expanded; } -ex simplify_indexed(const ex & e) +/** Simplify/canonicalize expression containing indexed objects. This + * performs contraction of dummy indices where possible and checks whether + * the free indices in sums are consistent. + * + * @return simplified expression */ +ex ex::simplify_indexed(void) const { - exvector free_indices; + exvector free_indices, dummy_indices; scalar_products sp; - return simplify_indexed(e, free_indices, sp); + return GiNaC::simplify_indexed(*this, free_indices, dummy_indices, sp); } -ex simplify_indexed(const ex & e, const scalar_products & sp) +/** Simplify/canonicalize expression containing indexed objects. This + * performs contraction of dummy indices where possible, checks whether + * the free indices in sums are consistent, and automatically replaces + * scalar products by known values if desired. + * + * @param sp Scalar products to be replaced automatically + * @return simplified expression */ +ex ex::simplify_indexed(const scalar_products & sp) const { - exvector free_indices; - return simplify_indexed(e, free_indices, sp); + exvector free_indices, dummy_indices; + return GiNaC::simplify_indexed(*this, free_indices, dummy_indices, sp); +} + +/** Symmetrize expression over its free indices. */ +ex ex::symmetrize(void) const +{ + return GiNaC::symmetrize(*this, get_free_indices()); +} + +/** Antisymmetrize expression over its free indices. */ +ex ex::antisymmetrize(void) const +{ + return GiNaC::antisymmetrize(*this, get_free_indices()); } ////////// @@ -762,6 +861,19 @@ void scalar_products::add(const ex & v1, const ex & v2, const ex & sp) spm[make_key(v1, v2)] = sp; } +void scalar_products::add_vectors(const lst & l) +{ + // Add all possible pairs of products + unsigned num = l.nops(); + for (unsigned i=0; i