在R中的矩阵中随机生成+1和-1

Question

如何在R中给定维度的矩阵中随机生成+1和-1？ 例如：对于大小为3 * 5的矩阵，矩阵可以是：

-1 -1  1  1 -1
 1 -1  1  1  1
-1 -1 -1 -1  1

Answer 1

尝试

nr = 3 # number of rows
nc = 5 # number of columns
M = matrix(sample(c(-1, 1), nr * nc, replace = TRUE), nrow = nr)
print(M)

     [,1] [,2] [,3] [,4] [,5]
[1,]   -1   -1   -1    1   -1
[2,]    1    1    1   -1   -1
[3,]    1    1    1    1    1