Change matrix dimension

Question

Let\'s make a replicable example:

This is my initial matrix

d<- matrix(1:80,,5)
d
     [,1] [,2] [,3] [,4] [,5]
[1,]    1   17   33   49   65
[2,         


        

Answer 1

We can try

d1 <- array(d, c(4, 4, 5))
do.call(rbind, lapply(seq(dim(d1)[3]), function(i) d1[,,i]))
#       [,1] [,2] [,3] [,4]
# [1,]    1    5    9   13
# [2,]    2    6   10   14
# [3,]    3    7   11   15
# [4,]    4    8   12   16
# [5,]   17   21   25   29
# [6,]   18   22   26   30
# [7,]   19   23   27   31
# [8,]   20   24   28   32
# [9,]   33   37   41   45
#[10,]   34   38   42   46
#[11,]   35   39   43   47
#[12,]   36   40   44   48
#[13,]   49   53   57   61
#[14,]   50   54   58   62
#[15,]   51   55   59   63
#[16,]   52   56   60   64
#[17,]   65   69   73   77
#[18,]   66   70   74   78
#[19,]   67   71   75   79
#[20,]   68   72   76   80