想象我有一個簡單的4x3x2陣列R.如何獲得R中數組的列索引矩陣?
> x <- array(1:24,c(4,3,2), dimnames=list(c('a','b','c','d'),c('x','y','z'),1:2))
> x
, , 1
x y z
a 1 5 9
b 2 6 10
c 3 7 11
d 4 8 12
, , 2
x y z
a 13 17 21
b 14 18 22
c 15 19 23
d 16 20 24
我想要什麼,是陣列上的簡單的功能,讓我回每個元素的任意維度索引的名稱。在這種情況下,尺寸2.
功能將這樣的表現:
> arraydims(x,2) #Where 2 is dimension I want names for.
, , 1
[,1] [,2] [,3]
[1,] "x" "y" "z"
[2,] "x" "y" "z"
[3,] "x" "y" "z"
[4,] "x" "y" "z"
, , 2
[,1] [,2] [,3]
[1,] "x" "y" "z"
[2,] "x" "y" "z"
[3,] "x" "y" "z"
[4,] "x" "y" "z"
是否必須作爲一個數組返回'庫(重塑)''y < - subset(melt(x),X3 == 2)' –