/* Copyright (C) 2004 Viktor T. Toth <http://www.vttoth.com/>
 *
 * 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 the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be
 * useful, but WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
 * PURPOSE.  See the GNU General Public License for more details.
 *
 * Algebraic classification of metrics
 *
 */

if get('ctensor,'version)=false then load(ctensor);
("Computing the Petrov classification of the Schwarzschild metric")$
("We use frames, set up simplification flags")$
(cframe_flag:true,gcd:spmod,ctrgsimp:true,ratwtlvl:false,ratfac:true);
("We use the stock Schwarzschild frame")$
ct_coordsys(exteriorschwarzschild,all);
("The inverse metric tensor is needed by nptetrad()")$
ug:invert(lg)$
("The basis for the calculations is the Weyl tensor")$
weyl(false);
("We compute a Newman-Penrose null tetrad")$
nptetrad(false);
("Now we're ready to compute the coefficients")$
psi(true);
("And obtain the Petrov class")$
petrov();

/* End of demo -- comment line needed by MAXIMA to resume demo menu */