TR2ROT Return rotational submatrix of a homogeneous transformation R = TR2ROT(T) Return R the 3x3 orthonormal rotation matrix from the homogeneous transformation T. SEE ALSO: ROT2TR
0001 %TR2ROT Return rotational submatrix of a homogeneous transformation 0002 % 0003 % R = TR2ROT(T) 0004 % 0005 % Return R the 3x3 orthonormal rotation matrix from the homogeneous 0006 % transformation T. 0007 % 0008 % SEE ALSO: ROT2TR 0009 0010 % Copyright (C) 1999-2008, by Peter I. Corke 0011 % 0012 % This file is part of The Robotics Toolbox for Matlab (RTB). 0013 % 0014 % RTB is free software: you can redistribute it and/or modify 0015 % it under the terms of the GNU Lesser General Public License as published by 0016 % the Free Software Foundation, either version 3 of the License, or 0017 % (at your option) any later version. 0018 % 0019 % RTB is distributed in the hope that it will be useful, 0020 % but WITHOUT ANY WARRANTY; without even the implied warranty of 0021 % MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 0022 % GNU Lesser General Public License for more details. 0023 % 0024 % You should have received a copy of the GNU Leser General Public License 0025 % along with RTB. If not, see <http://www.gnu.org/licenses/>. 0026 0027 function R = tr2rot(T) 0028 0029 if ~ishomog(T) 0030 error('input must be a homogeneous transform'); 0031 end 0032 0033 R = T(1:3,1:3);