如何在R矩阵中找到最小值和最大值的行数和列数？
矩阵可以具有一个或多个最小值和最大值。同样，矩阵的大小可以仅为一列多行，也可以为数千列和数千行。矩阵中最小值和最大值的行号和列号可以使用以下语法找到-
最大化
which(“Matrix_Name”==min(“Matrix_Name”),arr.ind=TRUE)
对于最低>
which(“Matrix_Name”==max(“Matrix_Name”),arr.ind=TRUE)
示例
M1<-matrix(1:25,ncol=5)
M1
[,1] [,2] [,3] [,4] [,5]
[1,] 1 6 11 16 21
[2,] 2 7 12 17 22
[3,] 3 8 13 18 23
[4,] 4 9 14 19 24
[5,] 5 10 15 20 25
which(M1==max(M1),arr.ind=TRUE)
row col
[1,] 5 5
which(M1==min(M1),arr.ind=TRUE)
row col
[1,] 1 1
M2<-matrix(rnorm(25),ncol=5)
M2
[,1] [,2] [,3] [,4] [,5]
[1,] -1.4194231 0.5835903 1.4665574 -1.6387592 0.7048224
[2,] 0.3352523 -0.2876772 1.1042358 -0.1989225 0.7347379
[3,] -1.5743547 0.4834883 -1.1198968 -0.6436345 -0.1437520
[4,] -2.1785618 1.6925537 1.5120286 -1.0856419 2.5269400
[5,] 0.9766656 2.0222188 -0.2966057 -0.1720232 -0.2257814
which(M2==max(M2),arr.ind=TRUE)
row col
[1,] 4 5
which(M2==min(M2),arr.ind=TRUE)
row col
[1,] 4 1
M3<-matrix(rnorm(25,2.5),ncol=5)
M3
[,1] [,2] [,3] [,4] [,5]
[1,] 3.670105 3.256981 1.925999 2.9184274 1.728779
[2,] 3.765994 3.205739 3.695557 4.0209779 2.434685
[3,] 1.748879 2.480154 3.676999 2.0010259 3.159799
[4,] 1.582952 2.676389 2.396969 0.3748771 1.165021
[5,] 1.720008 2.329690 2.409057 3.8057733 3.965829
which(M3==max(M3),arr.ind=TRUE)
row col
[1,] 2 4
which(M3==min(M3),arr.ind=TRUE)
row col
[1,] 4 4
M4<-matrix(rpois(36,2),ncol=6)
M4
[,1] [,2] [,3] [,4] [,5] [,6]
[1,] 2 2 1 3 1 1
[2,] 3 1 0 1 0 3
[3,] 0 1 4 1 4 2
[4,] 1 3 2 1 1 4
[5,] 1 2 0 1 2 1
[6,] 1 1 0 3 0 2
which(M4==max(M4),arr.ind=TRUE)
row col
[1,] 3 3
[2,] 3 5
[3,] 4 6
which(M4==min(M4),arr.ind=TRUE)
row col
[1,] 3 1
[2,] 2 3
[3,] 5 3
[4,] 6 3
[5,] 2 5
[6,] 6 5
M5<-matrix(rpois(36,10),ncol=6)
M5
[,1] [,2] [,3] [,4] [,5] [,6]
[1,] 11 10 13 10 10 8
[2,] 9 8 10 8 8 9
[3,] 8 11 8 7 9 10
[4,] 6 15 5 14 6 8
[5,] 11 7 11 9 8 12
[6,] 9 15 17 11 7 14
which(M5==max(M5),arr.ind=TRUE)
row col
[1,] 6 3
which(M5==min(M5),arr.ind=TRUE)
row col
[1,] 4 3
M6<-matrix(runif(36,2,5),ncol=6)
M6
[,1] [,2] [,3] [,4] [,5] [,6]
[1,] 3.652903 2.144873 4.801257 2.941041 4.132117 3.925266
[2,] 3.819255 2.695592 4.610663 2.062571 4.881452 3.256637
[3,] 2.203137 2.821375 2.481268 2.069606 4.042738 4.101515
[4,] 2.499690 3.593453 4.813508 2.304928 2.285617 3.713846
[5,] 3.684496 2.369803 4.974936 4.422779 2.097394 4.059585
[6,] 3.573778 3.780176 3.772600 2.699202 2.060818 2.948795
which(M6==max(M6),arr.ind=TRUE)
row col
[1,] 5 3
which(M6==min(M6),arr.ind=TRUE)
row col
[1,] 6 5