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transpose!

transpose!(dest,src)

Transpose array src and store the result in the preallocated array dest, which should have a size corresponding to (size(src,2),size(src,1)). No in-place transposition is supported and unexpected results will happen if src and dest have overlapping memory regions.

Examples

1. Transpose a matrix to a preallocated array:

   julia> src = [1 2 3; 4 5 6];
   julia> dest = zeros(Int, (size(src, 2), size(src, 1)));
   julia> transpose!(dest, src)
   3×2 Array{Int64,2}:
   1  4
   2  5
   3  6

   This example transposes the matrix src and stores the result in the preallocated array dest.

2. Transpose a 1x1 matrix:

   julia> src = [42];
   julia> dest = zeros(Int, (size(src, 2), size(src, 1)));
   julia> transpose!(dest, src)
   1×1 Array{Int64,2}:
   42

   It transposes a 1x1 matrix and stores the result in the preallocated array.

3. Ensure non-overlapping memory regions:

   julia> src = [1 2; 3 4];
   julia> dest = [0 0; 0 0];
   julia> transpose!(dest, src)
   2×2 Array{Int64,2}:
   1  3
   2  4

   It is important to ensure that src and dest do not have overlapping memory regions, as it may lead to unexpected results.

Common mistake example:

julia> src = [1 2 3; 4 5 6];
julia> dest = zeros(Int, (2, 3));
julia> transpose!(dest, src)
ERROR: DimensionMismatch("output dimensions must be compatible with input dimensions")

In this example, the size of the preallocated dest array does not match the expected size for the transpose operation. Ensure that dest has dimensions corresponding to (size(src, 2), size(src, 1)) to avoid such errors.

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