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/* 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 */
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