从solve()和ginv()得到错误的逆矩阵
`我试图得到一个逆矩阵
[,1] [,2] [,3]
[1,] 1 rou 0
[2,] rou 1+rou^2 rou
[3,] 0 rou 1
手工计算的逆矩阵应该是
1 rou rou^2
1/(1-rou) rou 1 rou
rou^2 rou 1
以rou = 0.3为例
a=matrix(c(1,0.3,0,0.3,1.09,0.3,0,0.3,1),nrow=3)
a
[,1] [,2] [,3]
[1,] 1.0 0.30 0.0
[2,] 0.3 1.09 0.3
[3,] 0.0 0.30 1.0
其手动计算的逆矩阵是以下矩阵
[,1] [,2] [,3]
[1,] 1.0989011 0.3296703 0.0989011
[2,] 0.3296703 1.0989011 0.3296703
[3,] 0.0989011 0.3296703 1.0989011
通过使用solve(a)或ginv(a)在R中,我得到了
[,1] [,2] [,3]
[1,] 1.0989011 -0.3296703 0.0989011
[2,] -0.3296703 1.0989011 -0.3296703
[3,] 0.0989011 -0.3296703 1.0989011
我想知道为什么有负面迹象.以前有人遇到过这个问题吗？怎么解决？
提前致谢!
跟进:我检查了%*%求解(a)并且确实如此
[,1] [,2] [,3]
[1,] 1.000000e+00 0 0
[2,] -6.938894e-18 1 0
[3,] 0.000000e+00 0 1
跟进2:我发现我的错误是我在计算辅助因子矩阵时忘了为某些元素添加负号
