X-Git-Url: https://www.ginac.de/ginac.git//ginac.git?p=ginac.git;a=blobdiff_plain;f=ginac%2Ftensor.cpp;h=07605e7a77cfa7ad87d33c67528ac54bb41fd0e2;hp=b7ae299838b3bb73003ac38e382ff615a31d5804;hb=d54e497297f4687c385ff8fbc91296365887c7c0;hpb=e9bd0d92d3573c4bcc24397914481cf9ed1aa6d1 diff --git a/ginac/tensor.cpp b/ginac/tensor.cpp index b7ae2998..07605e7a 100644 --- a/ginac/tensor.cpp +++ b/ginac/tensor.cpp @@ -3,7 +3,7 @@ * Implementation of GiNaC's special tensors. */ /* - * GiNaC Copyright (C) 1999-2002 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 @@ -29,33 +29,48 @@ #include "indexed.h" #include "symmetry.h" #include "relational.h" +#include "operators.h" #include "lst.h" #include "numeric.h" #include "matrix.h" -#include "print.h" #include "archive.h" #include "utils.h" namespace GiNaC { GINAC_IMPLEMENT_REGISTERED_CLASS(tensor, basic) -GINAC_IMPLEMENT_REGISTERED_CLASS(tensdelta, tensor) -GINAC_IMPLEMENT_REGISTERED_CLASS(tensmetric, tensor) -GINAC_IMPLEMENT_REGISTERED_CLASS(minkmetric, tensmetric) -GINAC_IMPLEMENT_REGISTERED_CLASS(spinmetric, tensmetric) -GINAC_IMPLEMENT_REGISTERED_CLASS(tensepsilon, tensor) + +GINAC_IMPLEMENT_REGISTERED_CLASS_OPT(tensdelta, tensor, + print_func(&tensdelta::do_print). + print_func(&tensdelta::do_print_latex)) + +GINAC_IMPLEMENT_REGISTERED_CLASS_OPT(tensmetric, tensor, + print_func(&tensmetric::do_print). + print_func(&tensmetric::do_print)) + +GINAC_IMPLEMENT_REGISTERED_CLASS_OPT(minkmetric, tensmetric, + print_func(&minkmetric::do_print). + print_func(&minkmetric::do_print_latex)) + +GINAC_IMPLEMENT_REGISTERED_CLASS_OPT(spinmetric, tensmetric, + print_func(&spinmetric::do_print). + print_func(&spinmetric::do_print_latex)) + +GINAC_IMPLEMENT_REGISTERED_CLASS_OPT(tensepsilon, tensor, + print_func(&tensepsilon::do_print). + print_func(&tensepsilon::do_print_latex)) ////////// -// default ctor, dtor, copy ctor, assignment operator and helpers +// constructors ////////// -DEFAULT_CTORS(tensor) -DEFAULT_CTORS(tensdelta) -DEFAULT_CTORS(tensmetric) -DEFAULT_COPY(spinmetric) -DEFAULT_DESTROY(spinmetric) -DEFAULT_DESTROY(minkmetric) -DEFAULT_DESTROY(tensepsilon) +tensor::tensor() : inherited(TINFO_tensor) +{ + setflag(status_flags::evaluated | status_flags::expanded); +} + +DEFAULT_CTOR(tensdelta) +DEFAULT_CTOR(tensmetric) minkmetric::minkmetric() : pos_sig(false) { @@ -72,12 +87,6 @@ minkmetric::minkmetric(bool ps) : pos_sig(ps) tinfo_key = TINFO_minkmetric; } -void minkmetric::copy(const minkmetric & other) -{ - inherited::copy(other); - pos_sig = other.pos_sig; -} - tensepsilon::tensepsilon() : minkowski(false), pos_sig(false) { tinfo_key = TINFO_tensepsilon; @@ -88,13 +97,6 @@ tensepsilon::tensepsilon(bool mink, bool ps) : minkowski(mink), pos_sig(ps) tinfo_key = TINFO_tensepsilon; } -void tensepsilon::copy(const tensepsilon & other) -{ - inherited::copy(other); - minkowski = other.minkowski; - pos_sig = other.pos_sig; -} - ////////// // archiving ////////// @@ -106,7 +108,7 @@ DEFAULT_ARCHIVING(spinmetric) DEFAULT_UNARCHIVE(minkmetric) DEFAULT_UNARCHIVE(tensepsilon) -minkmetric::minkmetric(const archive_node &n, const lst &sym_lst) : inherited(n, sym_lst) +minkmetric::minkmetric(const archive_node &n, lst &sym_lst) : inherited(n, sym_lst) { n.find_bool("pos_sig", pos_sig); } @@ -117,7 +119,7 @@ void minkmetric::archive(archive_node &n) const n.add_bool("pos_sig", pos_sig); } -tensepsilon::tensepsilon(const archive_node &n, const lst &sym_lst) : inherited(n, sym_lst) +tensepsilon::tensepsilon(const archive_node &n, lst &sym_lst) : inherited(n, sym_lst) { n.find_bool("minkowski", minkowski); n.find_bool("pos_sig", pos_sig); @@ -179,6 +181,16 @@ ex tensdelta::eval_indexed(const basic & i) const const idx & i1 = ex_to(i.op(1)); const idx & i2 = ex_to(i.op(2)); + // The dimension of the indices must be equal, otherwise we use the minimal + // dimension + if (!i1.get_dim().is_equal(i2.get_dim())) { + ex min_dim = i1.minimal_dim(i2); + exmap m; + m[i1] = i1.replace_dim(min_dim); + m[i2] = i2.replace_dim(min_dim); + return i.subs(m, subs_options::no_pattern); + } + // Trace of delta tensor is the (effective) dimension of the space if (is_dummy_pair(i1, i2)) { try { @@ -217,7 +229,10 @@ ex tensmetric::eval_indexed(const basic & i) const // dimension if (!i1.get_dim().is_equal(i2.get_dim())) { ex min_dim = i1.minimal_dim(i2); - return i.subs(lst(i1 == i1.replace_dim(min_dim), i2 == i2.replace_dim(min_dim))); + exmap m; + m[i1] = i1.replace_dim(min_dim); + m[i2] = i2.replace_dim(min_dim); + return i.subs(m, subs_options::no_pattern); } // A metric tensor with one covariant and one contravariant index gets @@ -305,15 +320,15 @@ ex tensepsilon::eval_indexed(const basic & i) const // a canonic order but we can't assume what exactly that order is) std::vector v; v.reserve(i.nops() - 1); - for (unsigned j=1; j(ex_to(i.op(j)).get_value()).to_int()); int sign = permutation_sign(v.begin(), v.end()); // In a Minkowski space, check for covariant indices if (minkowski) { - for (unsigned j=1; j(x)) throw(std::runtime_error("indices of epsilon tensor in Minkowski space must be of type varidx")); if (ex_to(x).is_covariant()) if (ex_to(x).get_value().is_zero()) @@ -339,7 +354,7 @@ bool tensor::replace_contr_index(exvector::iterator self, exvector::iterator oth again: if (self_idx->is_symbolic()) { - for (unsigned i=1; inops(); i++) { + for (size_t i=1; inops(); i++) { const idx &other_idx = ex_to(other->op(i)); if (is_dummy_pair(*self_idx, other_idx)) { @@ -393,11 +408,11 @@ bool tensmetric::contract_with(exvector::iterator self, exvector::iterator other // If contracting with the delta tensor, let the delta do it // (don't raise/lower delta indices) - if (is_ex_of_type(other->op(0), tensdelta)) + if (is_a(other->op(0))) return false; // Replace the dummy index with this tensor's other index and remove - // the tensor (this is valid for contractions with all other tensors) + // the tensor return replace_contr_index(self, other); } @@ -410,7 +425,7 @@ bool spinmetric::contract_with(exvector::iterator self, exvector::iterator other GINAC_ASSERT(is_a(self->op(0))); // Contractions between spinor metrics - if (is_ex_of_type(other->op(0), spinmetric)) { + if (is_a(other->op(0))) { const idx &self_i1 = ex_to(self->op(1)); const idx &self_i2 = ex_to(self->op(2)); const idx &other_i1 = ex_to(other->op(1)); @@ -443,7 +458,7 @@ bool spinmetric::contract_with(exvector::iterator self, exvector::iterator other // If contracting with the delta tensor, let the delta do it // (don't raise/lower delta indices) - if (is_ex_of_type(other->op(0), tensdelta)) + if (is_a(other->op(0))) return false; // Try to contract first index @@ -454,7 +469,7 @@ bool spinmetric::contract_with(exvector::iterator self, exvector::iterator other again: if (self_idx->is_symbolic()) { - for (unsigned i=1; inops(); i++) { + for (size_t i=1; inops(); i++) { const idx &other_idx = ex_to(other->op(i)); if (is_dummy_pair(*self_idx, other_idx)) { @@ -487,19 +502,21 @@ bool tensepsilon::contract_with(exvector::iterator self, exvector::iterator othe GINAC_ASSERT(is_a(*self)); GINAC_ASSERT(is_a(*other)); GINAC_ASSERT(is_a(self->op(0))); - unsigned num = self->nops() - 1; + size_t num = self->nops() - 1; - if (is_ex_exactly_of_type(other->op(0), tensepsilon) && num+1 == other->nops()) { + if (is_exactly_a(other->op(0)) && num+1 == other->nops()) { // Contraction of two epsilon tensors is a determinant - ex dim = ex_to(self->op(1)).get_dim(); + bool variance = is_a(self->op(1)); matrix M(num, num); - for (int i=0; iop(i+1), other->op(j+1), pos_sig); - else + else if (variance) M(i, j) = metric_tensor(self->op(i+1), other->op(j+1)); + else + M(i, j) = delta_tensor(self->op(i+1), other->op(j+1)); } } int sign = minkowski ? -1 : 1; @@ -517,7 +534,7 @@ bool tensepsilon::contract_with(exvector::iterator self, exvector::iterator othe ex delta_tensor(const ex & i1, const ex & i2) { - if (!is_ex_of_type(i1, idx) || !is_ex_of_type(i2, idx)) + if (!is_a(i1) || !is_a(i2)) throw(std::invalid_argument("indices of delta tensor must be of type idx")); return indexed(tensdelta(), sy_symm(), i1, i2); @@ -525,7 +542,7 @@ ex delta_tensor(const ex & i1, const ex & i2) ex metric_tensor(const ex & i1, const ex & i2) { - if (!is_ex_of_type(i1, varidx) || !is_ex_of_type(i2, varidx)) + if (!is_a(i1) || !is_a(i2)) throw(std::invalid_argument("indices of metric tensor must be of type varidx")); return indexed(tensmetric(), sy_symm(), i1, i2); @@ -533,7 +550,7 @@ ex metric_tensor(const ex & i1, const ex & i2) ex lorentz_g(const ex & i1, const ex & i2, bool pos_sig) { - if (!is_ex_of_type(i1, varidx) || !is_ex_of_type(i2, varidx)) + if (!is_a(i1) || !is_a(i2)) throw(std::invalid_argument("indices of metric tensor must be of type varidx")); return indexed(minkmetric(pos_sig), sy_symm(), i1, i2); @@ -541,7 +558,7 @@ ex lorentz_g(const ex & i1, const ex & i2, bool pos_sig) ex spinor_metric(const ex & i1, const ex & i2) { - if (!is_ex_of_type(i1, spinidx) || !is_ex_of_type(i2, spinidx)) + if (!is_a(i1) || !is_a(i2)) throw(std::invalid_argument("indices of spinor metric must be of type spinidx")); if (!ex_to(i1).get_dim().is_equal(2) || !ex_to(i2).get_dim().is_equal(2)) throw(std::runtime_error("index dimension for spinor metric must be 2")); @@ -551,7 +568,7 @@ ex spinor_metric(const ex & i1, const ex & i2) ex epsilon_tensor(const ex & i1, const ex & i2) { - if (!is_ex_of_type(i1, idx) || !is_ex_of_type(i2, idx)) + if (!is_a(i1) || !is_a(i2)) throw(std::invalid_argument("indices of epsilon tensor must be of type idx")); ex dim = ex_to(i1).get_dim(); @@ -565,7 +582,7 @@ ex epsilon_tensor(const ex & i1, const ex & i2) ex epsilon_tensor(const ex & i1, const ex & i2, const ex & i3) { - if (!is_ex_of_type(i1, idx) || !is_ex_of_type(i2, idx) || !is_ex_of_type(i3, idx)) + if (!is_a(i1) || !is_a(i2) || !is_a(i3)) throw(std::invalid_argument("indices of epsilon tensor must be of type idx")); ex dim = ex_to(i1).get_dim(); @@ -579,7 +596,7 @@ ex epsilon_tensor(const ex & i1, const ex & i2, const ex & i3) ex lorentz_eps(const ex & i1, const ex & i2, const ex & i3, const ex & i4, bool pos_sig) { - if (!is_ex_of_type(i1, varidx) || !is_ex_of_type(i2, varidx) || !is_ex_of_type(i3, varidx) || !is_ex_of_type(i4, varidx)) + if (!is_a(i1) || !is_a(i2) || !is_a(i3) || !is_a(i4)) throw(std::invalid_argument("indices of Lorentz epsilon tensor must be of type varidx")); ex dim = ex_to(i1).get_dim();