大家好，我想請問為什麼A1 and A2都可以把x rotate到y但是
A1 ~= A2
A2是由y/x算出來的，是否也叫做rotation matrix?
clear all
clc
x=[1
2
3]
%A1 is rotation matrix copied from wikipedia to rotate 30 degree around X
A1=[ 1.0000 0 0
0 0.8660 0.5000
0 -0.5000 0.8660]
% y is the rotated matrix
y1=A1*x
% A2 is y/x
A2=y1/x
% A2*x can recover y from x.
y2=A2*x
y2==y1
% but A2 is different then A1.
A2==A1

x=[1;2;3] ?

A2^T*A2 ~= eye(3)

可以去查查matlab的left division跟right division到底是在做什麼運算。