Clifford units now honor representation labels.

[ginac.git] / ginac / clifford.cpp

diff --git a/ginac/clifford.cpp b/ginac/clifford.cpp
index af54d77bbcb665ef7478c6dfd300c2d4aa4dd109..a434a882b804207a4c67b058cf776932ea20bfeb 100644 (file)
--- 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) 1999-2007 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<inherited>(c, level);
+       } else { // We do not print representation label if it is 0
+               if (representation_label == 0) {
+                       this->print_dispatch<inherited>(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
@@ -712,14 +725,14 @@ ex clifford_unit(const ex & mu, const ex & metr, unsigned char rl)
 
        exvector indices = metr.get_free_indices();
 
-       if ((indices.size() == 2) && is_a<varidx>(indices[0]) && is_a<varidx>(indices[1])) {
+       if (indices.size() == 2) {
                return clifford(unit, mu, metr, rl);
        } else if (is_a<matrix>(metr)) {
                matrix M = ex_to<matrix>(metr);
                unsigned n = M.rows();
                bool symmetric = true;
 
-               static varidx 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);
                if ((n ==  M.cols()) && (n == ex_to<idx>(mu).get_dim())) {
                        for (unsigned i = 0; i < n; i++) {
@@ -734,8 +747,8 @@ 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<varidx>(mu).get_dim()),
-                       chi((new symbol)->setflag(status_flags::dynallocated), ex_to<varidx>(mu).get_dim());
+               static varidx xi((new symbol)->setflag(status_flags::dynallocated), ex_to<idx>(mu).get_dim()),
+                       chi((new symbol)->setflag(status_flags::dynallocated), ex_to<idx>(mu).get_dim());
                return clifford(unit, mu, indexed(metr, xi, chi), rl);
        }  else 
                throw(std::invalid_argument("clifford_unit(): metric for Clifford unit must be of type tensor, matrix or an expression with two free indices"));
@@ -1292,14 +1305,16 @@ ex clifford_moebius_map(const ex & a, const ex & b, const ex & c, const ex & d,
        if (is_a<clifford>(G)) {
                cu = G;
        } else {
-               if (is_a<indexed>(G)) 
-                       D = ex_to<varidx>(G.op(1)).get_dim();
-               else if (is_a<matrix>(G)) 
+               if (is_a<indexed>(G)) {
+                       D = ex_to<idx>(G.op(1)).get_dim();
+                       varidx mu((new symbol)->setflag(status_flags::dynallocated), D);
+                       cu = clifford_unit(mu, G, rl);
+               } else if (is_a<matrix>(G)) {
                        D = ex_to<matrix>(G).rows(); 
-               else throw(std::invalid_argument("clifford_moebius_map(): metric should be an indexed object, matrix, or a Clifford unit"));
+                       idx mu((new symbol)->setflag(status_flags::dynallocated), D);
+                       cu = clifford_unit(mu, G, rl);
+               } else throw(std::invalid_argument("clifford_moebius_map(): metric should be an indexed object, matrix, or a Clifford unit"));
                
-               varidx mu((new symbol)->setflag(status_flags::dynallocated), D);
-               cu = clifford_unit(mu, G, rl);
        }
        
        x = lst_to_clifford(v, cu);