如何将稀疏矩阵转换为R中的矩阵？
稀疏矩阵是一种矩阵，其大多数元素等于零，但对零元素的数量没有限制。通常，非零元素的数量应等于行数或列数。要将稀疏矩阵转换为矩阵R，我们可以将as.matrix函数与稀疏矩阵对象名称一起使用。
例1
library(Matrix) i<−c(1,5,2,4,2,2,8);j<−c(2,5,3,2,4,2,4);x<−rpois(7,2) M1<−sparseMatrix(i,j,x=x) M1 8 x 5 sparse Matrix of class "dgCMatrix"输出结果
[1,] . 3 . . . [2,] . 5 3 3 . [3,] . . . . . [4,] . 2 . . . [5,] . . . . 4 [6,] . . . . . [7,] . . . . . [8,] . . . 3 .
示例
M1<−as.matrix(M1) M1输出结果
[,1] [,2] [,3] [,4] [,5] [1,] 0 3 0 0 0 [2,] 0 5 3 3 0 [3,] 0 0 0 0 0 [4,] 0 2 0 0 0 [5,] 0 0 0 0 4 [6,] 0 0 0 0 0 [7,] 0 0 0 0 0 [8,] 0 0 0 3 0
例2
i<−c(1,3,8,4,2,7,6,9,1,4,10);j<−c(2,5,3,2,4,2,4,5,2,7,3);x<−rpois(11,2) M2<−sparseMatrix(i,j,x=x) M2 10 x 7 sparse Matrix of class "dgCMatrix"输出结果
[1,] . 3 . . . . . [2,] . . . 0 . . . [3,] . . . . 3 . . [4,] . 1 . . . . 3 [5,] . . . . . . . [6,] . . . 0 . . . [7,] . 4 . . . . . [8,] . . 2 . . . . [9,] . . . . 1 . . [10,] . . 1 . . . .
示例
M2<−as.matrix(M2) M2输出结果
[,1] [,2] [,3] [,4] [,5] [,6] [,7] [1,] 0 3 0 0 0 0 0 [2,] 0 0 0 0 0 0 0 [3,] 0 0 0 0 3 0 0 [4,] 0 1 0 0 0 0 3 [5,] 0 0 0 0 0 0 0 [6,] 0 0 0 0 0 0 0 [7,] 0 4 0 0 0 0 0 [8,] 0 0 2 0 0 0 0 [9,] 0 0 0 0 1 0 0 [10,] 0 0 1 0 0 0 0
范例3
i<−c(1,3,8,4,2,7,6,9,1,4,10);j<−c(2,5,3,2,4,2,4,5,2,7,3);x<−rpois(11,5) M3<−sparseMatrix(i,j,x=x) M3 10 x 7 sparse Matrix of class "dgCMatrix"输出结果
[1,] . 8 . . . . . [2,] . . . 8 . . . [3,] . . . . 3 . . [4,] . 7 . . . . 7 [5,] . . . . . . . [6,] . . . 8 . . . [7,] . 3 . . . . . [8,] . . 12 . . . . [9,] . . . . 2 . . [10,] . . 9 . . . .
示例
M3<−as.matrix(M3) M3输出结果
[,1] [,2] [,3] [,4] [,5] [,6] [,7] [1,] 0 8 0 0 0 0 0 [2,] 0 0 0 8 0 0 0 [3,] 0 0 0 0 3 0 0 [4,] 0 7 0 0 0 0 7 [5,] 0 0 0 0 0 0 0 [6,] 0 0 0 8 0 0 0 [7,] 0 3 0 0 0 0 0 [8,] 0 0 12 0 0 0 0 [9,] 0 0 0 0 2 0 0 [10,] 0 0 9 0 0 0 0
例子4
i<−c(1,3,8,4,2,7,6,9,1,4,10,5,11,2,12);j<−c(2,5,3,8,6,2,4,2,4,5,2,7,3,2,1);x<−rpois(15,5) M4<−sparseMatrix(i,j,x=x) M4 12 x 8 sparse Matrix of class "dgCMatrix"输出结果
[1,] . 3 . 3 . . . . [2,] . 6 . . . 6 . . [3,] . . . . 2 . . . [4,] . . . . 3 . . 6 [5,] . . . . . . 6 . [6,] . . . 6 . . . . [7,] . 5 . . . . . . [8,] . . 4 . . . . . [9,] . 2 . . . . . . [10,] . 2 . . . . . . [11,] . . 5 . . . . . [12,] 6 . . . . . . .
示例
M4<−as.matrix(M4) M4输出结果
[,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [1,] 0 3 0 3 0 0 0 0 [2,] 0 6 0 0 0 6 0 0 [3,] 0 0 0 0 2 0 0 0 [4,] 0 0 0 0 3 0 0 6 [5,] 0 0 0 0 0 0 6 0 [6,] 0 0 0 6 0 0 0 0 [7,] 0 5 0 0 0 0 0 0 [8,] 0 0 4 0 0 0 0 0 [9,] 0 2 0 0 0 0 0 0 [10,] 0 2 0 0 0 0 0 0 [11,] 0 0 5 0 0 0 0 0 [12,] 6 0 0 0 0 0 0 0
范例5
i<−c(1,3,8,4,2,7,6,9,1,4,10,5,11,2,12);j<−c(2,5,3,8,6,2,4,2,4,5,2,7,3,2,1);x<−round(rnorm(15),2) M5<−sparseMatrix(i,j,x=x) M5 12 x 8 sparse Matrix of class "dgCMatrix"输出结果
[1,] . −0.65 . 0.38 . . . . [2,] . 0.93 . . . 0.56 . . [3,] . . . . −1.02 . . . [4,] . . . . −1.10 . . 0.35 [5,] . . . . . . 1.47 . [6,] . . . −0.27 . . . . [7,] . 1.31 . . . . . . [8,] . . 0.23 . . . . . [9,] . 1.47 . . . . . . [10,] . 1.24 . . . . . . [11,] . . −1.63 . . . . . [12,] 0.92 . . . . . . .
示例
M5<−as.matrix(M5) M5输出结果
[,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [1,] 0.00 −0.65 0.00 0.38 0.00 0.00 0.00 0.00 [2,] 0.00 0.93 0.00 0.00 0.00 0.56 0.00 0.00 [3,] 0.00 0.00 0.00 0.00 −1.02 0.00 0.00 0.00 [4,] 0.00 0.00 0.00 0.00 −1.10 0.00 0.00 0.35 [5,] 0.00 0.00 0.00 0.00 0.00 0.00 1.47 0.00 [6,] 0.00 0.00 0.00 −0.27 0.00 0.00 0.00 0.00 [7,] 0.00 1.31 0.00 0.00 0.00 0.00 0.00 0.00 [8,] 0.00 0.00 0.23 0.00 0.00 0.00 0.00 0.00 [9,] 0.00 1.47 0.00 0.00 0.00 0.00 0.00 0.00 [10,] 0.00 1.24 0.00 0.00 0.00 0.00 0.00 0.00 [11,] 0.00 0.00 −1.63 0.00 0.00 0.00 0.00 0.00 [12,] 0.92 0.00 0.00 0.00 0.00 0.00 0.00 0.00