Mercurial > forge
view main/quaternion/inst/@quaternion/mtimes.m @ 9892:8ad402be2313 octave-forge
main/quaternion --> extra/quaternion-legacy, extra/quaternion_oo --> main/quaternion
author | paramaniac |
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date | Wed, 28 Mar 2012 03:16:58 +0000 |
parents | extra/quaternion_oo/inst/@quaternion/mtimes.m@ce33c133cad7 |
children | c04bb762824e |
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## Copyright (C) 2010 Lukas F. Reichlin ## ## 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 3 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. ## ## You should have received a copy of the GNU General Public License ## along with this program. If not, see <http://www.gnu.org/licenses/>. ## -*- texinfo -*- ## Matrix multiplication of two quaternions. Used by Octave for "q1 * q2". ## Author: Lukas Reichlin <lukas.reichlin@gmail.com> ## Created: May 2010 ## Version: 0.1 function a = mtimes (a, b) if (! isa (a, "quaternion")) a = quaternion (a); endif if (! isa (b, "quaternion")) b = quaternion (b); endif w = a.w*b.w - a.x*b.x - a.y*b.y - a.z*b.z; x = a.y*b.z - a.z*b.y + a.w*b.x + a.x*b.w; y = a.z*b.x - a.x*b.z + a.w*b.y + a.y*b.w; z = a.x*b.y - a.y*b.x + a.w*b.z + a.z*b.w; a.w = w; a.x = x; a.y = y; a.z = z; endfunction