Define function to create a 'diagonal' array or get the diagonal of an array

Usage

diag4Darray(x = 1, dim = length(x))

Arguments

x: number or vector defining the value of the diagonal of 4D array
dim: integer defining the length of the diagonal. Default is length(x). If length(x) != 1, dim must be equal to length(x).

Value

array with all elements zero except the diagonal, with dimensions c(dim,dim,dim)

Details

The diagonal of a 4D array has been defined as those elements in positions c(int,int,int,int), i.e., the four digits are the same.

Examples

x <- diag4Darray(c(1,3,6,2), dim = 4)
x
#> , , 1, 1
#> 
#>      [,1] [,2] [,3] [,4]
#> [1,]    1    0    0    0
#> [2,]    0    0    0    0
#> [3,]    0    0    0    0
#> [4,]    0    0    0    0
#> 
#> , , 2, 1
#> 
#>      [,1] [,2] [,3] [,4]
#> [1,]    0    0    0    0
#> [2,]    0    0    0    0
#> [3,]    0    0    0    0
#> [4,]    0    0    0    0
#> 
#> , , 3, 1
#> 
#>      [,1] [,2] [,3] [,4]
#> [1,]    0    0    0    0
#> [2,]    0    0    0    0
#> [3,]    0    0    0    0
#> [4,]    0    0    0    0
#> 
#> , , 4, 1
#> 
#>      [,1] [,2] [,3] [,4]
#> [1,]    0    0    0    0
#> [2,]    0    0    0    0
#> [3,]    0    0    0    0
#> [4,]    0    0    0    0
#> 
#> , , 1, 2
#> 
#>      [,1] [,2] [,3] [,4]
#> [1,]    0    0    0    0
#> [2,]    0    0    0    0
#> [3,]    0    0    0    0
#> [4,]    0    0    0    0
#> 
#> , , 2, 2
#> 
#>      [,1] [,2] [,3] [,4]
#> [1,]    0    0    0    0
#> [2,]    0    3    0    0
#> [3,]    0    0    0    0
#> [4,]    0    0    0    0
#> 
#> , , 3, 2
#> 
#>      [,1] [,2] [,3] [,4]
#> [1,]    0    0    0    0
#> [2,]    0    0    0    0
#> [3,]    0    0    0    0
#> [4,]    0    0    0    0
#> 
#> , , 4, 2
#> 
#>      [,1] [,2] [,3] [,4]
#> [1,]    0    0    0    0
#> [2,]    0    0    0    0
#> [3,]    0    0    0    0
#> [4,]    0    0    0    0
#> 
#> , , 1, 3
#> 
#>      [,1] [,2] [,3] [,4]
#> [1,]    0    0    0    0
#> [2,]    0    0    0    0
#> [3,]    0    0    0    0
#> [4,]    0    0    0    0
#> 
#> , , 2, 3
#> 
#>      [,1] [,2] [,3] [,4]
#> [1,]    0    0    0    0
#> [2,]    0    0    0    0
#> [3,]    0    0    0    0
#> [4,]    0    0    0    0
#> 
#> , , 3, 3
#> 
#>      [,1] [,2] [,3] [,4]
#> [1,]    0    0    0    0
#> [2,]    0    0    0    0
#> [3,]    0    0    6    0
#> [4,]    0    0    0    0
#> 
#> , , 4, 3
#> 
#>      [,1] [,2] [,3] [,4]
#> [1,]    0    0    0    0
#> [2,]    0    0    0    0
#> [3,]    0    0    0    0
#> [4,]    0    0    0    0
#> 
#> , , 1, 4
#> 
#>      [,1] [,2] [,3] [,4]
#> [1,]    0    0    0    0
#> [2,]    0    0    0    0
#> [3,]    0    0    0    0
#> [4,]    0    0    0    0
#> 
#> , , 2, 4
#> 
#>      [,1] [,2] [,3] [,4]
#> [1,]    0    0    0    0
#> [2,]    0    0    0    0
#> [3,]    0    0    0    0
#> [4,]    0    0    0    0
#> 
#> , , 3, 4
#> 
#>      [,1] [,2] [,3] [,4]
#> [1,]    0    0    0    0
#> [2,]    0    0    0    0
#> [3,]    0    0    0    0
#> [4,]    0    0    0    0
#> 
#> , , 4, 4
#> 
#>      [,1] [,2] [,3] [,4]
#> [1,]    0    0    0    0
#> [2,]    0    0    0    0
#> [3,]    0    0    0    0
#> [4,]    0    0    0    2
#> 
# , , 1, 1
#
#      [,1] [,2] [,3] [,4]
# [1,]    1    0    0    0
# [2,]    0    0    0    0
# [3,]    0    0    0    0
# [4,]    0    0    0    0
#
# , , 2, 1
#
#      [,1] [,2] [,3] [,4]
# [1,]    0    0    0    0
# [2,]    0    0    0    0
# [3,]    0    0    0    0
# [4,]    0    0    0    0
#
# , , 3, 1
#
#      [,1] [,2] [,3] [,4]
# [1,]    0    0    0    0
# [2,]    0    0    0    0
# [3,]    0    0    0    0
# [4,]    0    0    0    0
#
# , , 4, 1
#
#      [,1] [,2] [,3] [,4]
# [1,]    0    0    0    0
# [2,]    0    0    0    0
# [3,]    0    0    0    0
# [4,]    0    0    0    0
#
# , , 1, 2
#
#      [,1] [,2] [,3] [,4]
# [1,]    0    0    0    0
# [2,]    0    0    0    0
# [3,]    0    0    0    0
# [4,]    0    0    0    0
#
# , , 2, 2
#
#      [,1] [,2] [,3] [,4]
# [1,]    0    0    0    0
# [2,]    0    3    0    0
# [3,]    0    0    0    0
# [4,]    0    0    0    0
#
# , , 3, 2
#
#      [,1] [,2] [,3] [,4]
# [1,]    0    0    0    0
# [2,]    0    0    0    0
# [3,]    0    0    0    0
# [4,]    0    0    0    0
#
# , , 4, 2
#
#      [,1] [,2] [,3] [,4]
# [1,]    0    0    0    0
# [2,]    0    0    0    0
# [3,]    0    0    0    0
# [4,]    0    0    0    0
#
# , , 1, 3
#
#      [,1] [,2] [,3] [,4]
# [1,]    0    0    0    0
# [2,]    0    0    0    0
# [3,]    0    0    0    0
# [4,]    0    0    0    0
#
# , , 2, 3
#
#      [,1] [,2] [,3] [,4]
# [1,]    0    0    0    0
# [2,]    0    0    0    0
# [3,]    0    0    0    0
# [4,]    0    0    0    0
#
# , , 3, 3
#
#      [,1] [,2] [,3] [,4]
# [1,]    0    0    0    0
# [2,]    0    0    0    0
# [3,]    0    0    6    0
# [4,]    0    0    0    0
#
# , , 4, 3
#
#      [,1] [,2] [,3] [,4]
# [1,]    0    0    0    0
# [2,]    0    0    0    0
# [3,]    0    0    0    0
# [4,]    0    0    0    0
#
# , , 1, 4
#
#      [,1] [,2] [,3] [,4]
# [1,]    0    0    0    0
# [2,]    0    0    0    0
# [3,]    0    0    0    0
# [4,]    0    0    0    0
#
# , , 2, 4
#
#      [,1] [,2] [,3] [,4]
# [1,]    0    0    0    0
# [2,]    0    0    0    0
# [3,]    0    0    0    0
# [4,]    0    0    0    0
#
# , , 3, 4
#
#      [,1] [,2] [,3] [,4]
# [1,]    0    0    0    0
# [2,]    0    0    0    0
# [3,]    0    0    0    0
# [4,]    0    0    0    0
#
# , , 4, 4
#
#      [,1] [,2] [,3] [,4]
# [1,]    0    0    0    0
# [2,]    0    0    0    0
# [3,]    0    0    0    0
# [4,]    0    0    0    2
diag4Darray(x)
#> [1] 1 3 6 2
# 1, 3, 6, 2