X-Git-Url: https://www.ginac.de/ginac.git//ginac.git?a=blobdiff_plain;ds=sidebyside;f=ginac%2Fclifford.cpp;h=c76fff234cf57bbbc24b9797c2bc96e1637a0f75;hb=6335b2cfb6f3f9ec339ff683bed415a5879d7909;hp=a0393011af5247cca9e94cd9aacd1059962ebc3f;hpb=a6b2ee0043599892559ef72bacaaae3bcf8a96d0;p=ginac.git diff --git a/ginac/clifford.cpp b/ginac/clifford.cpp index a0393011..c76fff23 100644 --- a/ginac/clifford.cpp +++ b/ginac/clifford.cpp @@ -3,7 +3,7 @@ * Implementation of GiNaC's clifford algebra (Dirac gamma) objects. */ /* - * GiNaC Copyright (C) 1999-2006 Johannes Gutenberg University Mainz, Germany + * GiNaC Copyright (C) 1999-2008 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 @@ -265,8 +265,21 @@ void clifford::do_print_dflt(const print_dflt & c, unsigned level) const if (is_dirac_slash(seq[0])) { seq[0].print(c, precedence()); c.s << "\\"; - } else - this->print_dispatch(c, level); + } else { // We do not print representation label if it is 0 + if (representation_label == 0) { + this->print_dispatch(c, level); + } else { // otherwise we put it before indices in square brackets; the code is borrowed from indexed.cpp + if (precedence() <= level) { + c.s << '('; + } + seq[0].print(c, precedence()); + c.s << '[' << int(representation_label) << ']'; + printindices(c, level); + if (precedence() <= level) { + c.s << ')'; + } + } + } } void clifford::do_print_latex(const print_latex & c, unsigned level) const @@ -703,9 +716,21 @@ ex dirac_ONE(unsigned char rl) return clifford(ONE, rl); } +static unsigned get_dim_uint(const ex& e) +{ + if (!is_a(e)) + throw std::invalid_argument("get_dim_uint: argument is not an index"); + ex dim = ex_to(e).get_dim(); + if (!dim.info(info_flags::posint)) + throw std::invalid_argument("get_dim_uint: dimension of index should be a positive integer"); + unsigned d = ex_to(dim).to_int(); + return d; +} + ex clifford_unit(const ex & mu, const ex & metr, unsigned char rl) { - static ex unit = (new cliffordunit)->setflag(status_flags::dynallocated); + //static ex unit = (new cliffordunit)->setflag(status_flags::dynallocated); + ex unit = (new cliffordunit)->setflag(status_flags::dynallocated); if (!is_a(mu)) throw(std::invalid_argument("clifford_unit(): index of Clifford unit must be of type idx or varidx")); @@ -719,12 +744,14 @@ ex clifford_unit(const ex & mu, const ex & metr, unsigned char rl) unsigned n = M.rows(); bool symmetric = true; - static idx xi((new symbol)->setflag(status_flags::dynallocated), n), + //static idx xi((new symbol)->setflag(status_flags::dynallocated), n), + // chi((new symbol)->setflag(status_flags::dynallocated), n); + idx xi((new symbol)->setflag(status_flags::dynallocated), n), chi((new symbol)->setflag(status_flags::dynallocated), n); - if ((n == M.cols()) && (n == ex_to(mu).get_dim())) { + if ((n == M.cols()) && (n == get_dim_uint(mu))) { for (unsigned i = 0; i < n; i++) { for (unsigned j = i+1; j < n; j++) { - if (M(i, j) != M(j, i)) { + if (!M(i, j).is_equal(M(j, i))) { symmetric = false; } } @@ -734,7 +761,9 @@ ex clifford_unit(const ex & mu, const ex & metr, unsigned char rl) throw(std::invalid_argument("clifford_unit(): metric for Clifford unit must be a square matrix with the same dimensions as index")); } } else if (indices.size() == 0) { // a tensor or other expression without indices - static varidx xi((new symbol)->setflag(status_flags::dynallocated), ex_to(mu).get_dim()), + //static varidx xi((new symbol)->setflag(status_flags::dynallocated), ex_to(mu).get_dim()), + // chi((new symbol)->setflag(status_flags::dynallocated), ex_to(mu).get_dim()); + varidx xi((new symbol)->setflag(status_flags::dynallocated), ex_to(mu).get_dim()), chi((new symbol)->setflag(status_flags::dynallocated), ex_to(mu).get_dim()); return clifford(unit, mu, indexed(metr, xi, chi), rl); } else @@ -1157,7 +1186,7 @@ ex lst_to_clifford(const ex & v, const ex & e) { ex mu = e.op(1); ex mu_toggle = is_a(mu) ? ex_to(mu).toggle_variance() : mu; - unsigned dim = (ex_to(ex_to(mu).get_dim())).to_int(); + unsigned dim = get_dim_uint(mu); if (is_a(v)) { if (ex_to(v).cols() > ex_to(v).rows()) { @@ -1170,13 +1199,20 @@ ex lst_to_clifford(const ex & v, const ex & e) { if (min == 1) { if (dim == max) return indexed(v, mu_toggle) * e; - else + else if (max - dim == 1) { + if (ex_to(v).cols() > ex_to(v).rows()) + return v.op(0) * dirac_ONE(ex_to(e).get_representation_label()) + indexed(sub_matrix(ex_to(v), 0, 1, 1, dim), mu_toggle) * e; + else + return v.op(0) * dirac_ONE(ex_to(e).get_representation_label()) + indexed(sub_matrix(ex_to(v), 1, dim, 0, 1), mu_toggle) * e; + } else throw(std::invalid_argument("lst_to_clifford(): dimensions of vector and clifford unit mismatch")); } else throw(std::invalid_argument("lst_to_clifford(): first argument should be a vector (nx1 or 1xn matrix)")); } else if (v.info(info_flags::list)) { if (dim == ex_to(v).nops()) return indexed(matrix(dim, 1, ex_to(v)), mu_toggle) * e; + else if (ex_to(v).nops() - dim == 1) + return v.op(0) * dirac_ONE(ex_to(e).get_representation_label()) + indexed(sub_matrix(matrix(dim+1, 1, ex_to(v)), 1, dim, 0, 1), mu_toggle) * e; else throw(std::invalid_argument("lst_to_clifford(): list length and dimension of clifford unit mismatch")); } else @@ -1261,19 +1297,28 @@ lst clifford_to_lst(const ex & e, const ex & c, bool algebraic) or (not is_a(pow(c.subs(mu == i, subs_options::no_pattern), 2)))) algebraic = false; lst V; + ex v0 = remove_dirac_ONE(canonicalize_clifford(e+clifford_prime(e)).normal())/2; + if (not v0.is_zero()) + V.append(v0); + ex e1 = canonicalize_clifford(e - v0 * dirac_ONE(ex_to(c).get_representation_label())); if (algebraic) { for (unsigned int i = 0; i < D; i++) V.append(remove_dirac_ONE( - simplify_indexed(canonicalize_clifford(e * c.subs(mu == i, subs_options::no_pattern) + c.subs(mu == i, subs_options::no_pattern) * e)) + simplify_indexed(canonicalize_clifford(e1 * c.subs(mu == i, subs_options::no_pattern) + c.subs(mu == i, subs_options::no_pattern) * e1)) / (2*pow(c.subs(mu == i, subs_options::no_pattern), 2)))); } else { - ex e1 = canonicalize_clifford(e); try { for (unsigned int i = 0; i < D; i++) V.append(get_clifford_comp(e1, c.subs(c.op(1) == i, subs_options::no_pattern))); } catch (std::exception &p) { /* Try to expand dummy summations to simplify the expression*/ - e1 = canonicalize_clifford(expand_dummy_sum(e1, true)); + e1 = canonicalize_clifford(expand_dummy_sum(e, true)); + V.remove_all(); + v0 = remove_dirac_ONE(canonicalize_clifford(e1+clifford_prime(e1)).normal())/2; + if (not v0.is_zero()) { + V.append(v0); + e1 = canonicalize_clifford(e1 - v0 * dirac_ONE(ex_to(c).get_representation_label())); + } for (unsigned int i = 0; i < D; i++) V.append(get_clifford_comp(e1, c.subs(c.op(1) == i, subs_options::no_pattern))); } @@ -1311,11 +1356,10 @@ ex clifford_moebius_map(const ex & a, const ex & b, const ex & c, const ex & d, ex clifford_moebius_map(const ex & M, const ex & v, const ex & G, unsigned char rl) { - if (is_a(M)) - return clifford_moebius_map(ex_to(M)(0,0), ex_to(M)(0,1), - ex_to(M)(1,0), ex_to(M)(1,1), v, G, rl); + if (is_a(M) && (ex_to(M).rows() == 2) && (ex_to(M).cols() == 2)) + return clifford_moebius_map(M.op(0), M.op(1), M.op(2), M.op(3), v, G, rl); else - throw(std::invalid_argument("clifford_moebius_map(): parameter M should be a matrix")); + throw(std::invalid_argument("clifford_moebius_map(): parameter M should be a 2x2 matrix")); } } // namespace GiNaC