
Re: Quicker way to rotate a 3 dimensional array?
Posted:
Jan 28, 2013 2:31 AM


"Phil " <matlab@test.com> wrote in message <ke4thb$s7j$1@newscl01ah.mathworks.com>... > I've got an array that is three dimensional where the first two dimensions are relatively large numbers and the third has length 3. This third one contains x,y,z coordinates that I would like to rotate about the x axis. I've managed to do this using: > > tmp3 = tmp; > k = 0; > for i=1:height > for j=1:width > k = k + 1; > tmp3(i,j,:) = reshape(tmp(i,j,:),1,3)*[1,0,0;0,cos(theta),sin(theta);0,sin(theta),cos(theta)]; > end > end
R = [ 1,0,0; 0,cos(theta),sin(theta); 0,sin(theta),cos(theta)]
[nx ny nz] = size(temp); temp3 = reshape(reshape(temp,[],3)*R, [nx ny 3]);
% Bruno

