3×3の対角行列を生成する
> diag(3)
[,1] [,2] [,3]
[1,] 1 0 0
[2,] 0 1 0
[3,] 0 0 1
3×3の対角行列を生成し、対角成分を更新する
# 3x3の行列を生成する > a <- matrix(c(0,1,2,3,4,5,6,7,9), 3,3) > a [,1] [,2] [,3] [1,] 0 3 6 [2,] 1 4 7 [3,] 2 5 9 # 対角成分を取得する > diag(a) [1] 0 4 9 #対角成分を入れ替える > diag(a) <- 0 > a [,1] [,2] [,3] [1,] 0 3 6 [2,] 1 0 7 [3,] 2 5 0