复制2维矩阵以创建3维数组(以R表示) [英] Replicating 2 dimensional matrix to create a 3 dimensional array (in R)

问题描述

我有一个二维矩阵，我想复制10次以创建一个三维数组，其中数组的每个切片"都是二维数组的相同副本.

I have a two dimensional matrix that I would like to replicate 10 times to create a three dimensional array where each 'slice' of the array is an identical copy of the two dimensional array.

所以，如果我的2D数组是:

So, if my 2D array were to be:

a <- matrix(c(1:4),nrow=2)
> a
     [,1] [,2]
[1,]    1    2
[2,]    3    4

我想要这样输出一个数组:

I would like as output an array like this:

, , 1

     [,1] [,2]
[1,]    1    2
[2,]    3    4

, , 2

     [,1] [,2]
[1,]    1    2
[2,]    3    4

....

, , 10

     [,1] [,2]
[1,]    1    2
[2,]    3    4

我看过此页面(复制矩阵到表单列表)，其中OP希望将矩阵复制到列表中，然后我将其转换为数组:

I have seen this page (Duplicate matrix to form list), in which the OP was looking to duplicate matrices to a list, which I adapted to then convert to an array:

b<-rep(list(a), 10) # from original post
array(unlist(b), dim = c(nrow(b[[1]]), ncol(b[[1]]), length(b))) # line I added

这很好，但是有点回旋-我想知道是否有一种方法可以在一行中完成此操作而无需创建列表.

This works fine but it's a little roundabout - I was wondering if there were a way to do this in one line without going through the creation of a list.

我尝试以rbind的方式应用do.call的逻辑，以将多行绑定在一起，但改用abind-

I tried applying the logic of a do.call in the way that is done with rbind to bind multiple rows together, but using abind instead -

do.call(abind,as.list(c(a,a,a,a,a,a,a,a,a,a))) 

但是输出是一个长向量，所以不是我想要的.

but the output was one long vector and so not what I was looking for.

任何帮助将不胜感激！

推荐答案

，您可以使用replicate，默认情况下会生成一个列表.要获取数组，请添加simple ="array".

you can use replicate, which produces a list by default. To get an array, add simplify = "array".

replicate(10, a, simplify="array")

, , 1

     [,1] [,2]
[1,]    1    3
[2,]    2    4

, , 2

     [,1] [,2]
[1,]    1    3
[2,]    2    4

...

, , 9

     [,1] [,2]
[1,]    1    3
[2,]    2    4

, , 10

     [,1] [,2]
[1,]    1    3
[2,]    2    4

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