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repeat

repeat(A, inner = Int[], outer = Int[])

Construct an array by repeating the entries of A. The i-th element of inner specifies the number of times that the individual entries of the i-th dimension of A should be repeated. The i-th element of outer specifies the number of times that a slice along the i-th dimension of A should be repeated.

Examples

1. Repeat elements of an array:

   julia> A = [1, 2, 3];
   julia> repeat(A, inner = [2])
   6-element Array{Int64,1}:
   1
   1
   2
   2
   3
   3

   This example repeats each element of array A twice.

2. Repeat rows of a matrix:

   julia> A = [1 2; 3 4];
   julia> repeat(A, outer = [2])
   4×2 Array{Int64,2}:
   1  2
   1  2
   3  4
   3  4

   It repeats each row of matrix A twice.

3. Repeat elements of a multi-dimensional array:

   julia> A = [1 2; 3 4];
   julia> repeat(A, inner = [1, 2], outer = [2])
   4×4 Array{Int64,2}:
   1  2  1  2
   3  4  3  4
   1  2  1  2
   3  4  3  4

   This example repeats each element of A along the second dimension twice and repeats the entire matrix twice along the first dimension.

Common mistake example:

julia> A = [1, 2, 3];
julia> repeat(A, inner = [2, 3])
ERROR: DimensionMismatch("repeat dimensions must be either 1 or equal to size(A)")

Here, the inner parameter specifies a different number of repeats for each dimension, resulting in a DimensionMismatch error. The inner and outer dimensions should either be of size 1 or match the corresponding dimensions of A to avoid this error.

See Also

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