问题描述
我在MATLAB中有一个旋转矩阵
PC=[0.4822 0.5070 0.7145
-0.4086 0.8516 -0.3285
0.7750 0.1336 -0.6177];
quat=rotm2quat(PC); %gives me
[0.3937,0.8641,0.0319,0.3119] %which is [w,x,y,z]
Python中的相同矩阵
from scipy.spatial.transform import Rotation as R
rot=[[0.4822,0.5070,0.7145],[-0.4086,0.8516,-0.3285],[ 0.7750,0.1336,-0.6177]]
r=R.from_dcm(rot)
print(r.as_quat()) # gives me following
[ 0.04920064 0.99356301 -0.09745128 -0.0302504 ] # which is [x,z,w]
为什么四元数值[x,w]在MATLAB和python之间不匹配。
解决方法
PC不是有效的方向余弦（即旋转）矩阵。行列式应接近1，但实际上接近-1。将此PC馈入任何期望方向余弦矩阵的例程将不会产生正确的结果。您需要检查如何生成此PC矩阵并进行修复。我什至无法复制您的四元数。例如，
df1 <- structure(list(tree = c("C1T1","C1T1","C1T2","C1T2"),cookie = c("A","B","C","A","C"),age = c(113L,108L,97L,133L,110L,100L)),class = "data.frame",row.names = c(NA,-6L))