R-随机组合两个向量
我有两个这样的向量:R-随机组合两个向量,r,R,我有两个这样的向量: a <- c(a,b,c) b <- c(1,2,3) a您可以使用expand.grid: a <- c("a","b","c") b <- c(1,2,3) expand.grid(a, b) Var1 Var2 1 a 1 2 b 1 3 c 1 4 a 2 5 b 2 6 c 2 7 a 3 8 b 3 9
a <- c(a,b,c)
b <- c(1,2,3)
a您可以使用expand.grid
:
a <- c("a","b","c")
b <- c(1,2,3)
expand.grid(a, b)
Var1 Var2
1 a 1
2 b 1
3 c 1
4 a 2
5 b 2
6 c 2
7 a 3
8 b 3
9 c 3
a您也可以使用:
library(data.table)
as.matrix(CJ(a,b))
# V1 V2
#[1,] "a" "1"
#[2,] "a" "2"
#[3,] "a" "3"
#[4,] "b" "1"
#[5,] "b" "2"
#[6,] "b" "3"
#[7,] "c" "1"
#[8,] "c" "2"
#[9,] "c" "3"
z
看起来不像随机组合。@Jay解释一下“随机”是什么意思
library(data.table)
as.matrix(CJ(a,b))
# V1 V2
#[1,] "a" "1"
#[2,] "a" "2"
#[3,] "a" "3"
#[4,] "b" "1"
#[5,] "b" "2"
#[6,] "b" "3"
#[7,] "c" "1"
#[8,] "c" "2"
#[9,] "c" "3"