For example copy the second two columns to the first: [1 2 3; 1 2 3; 1 2 3] becomes [2 3 3; 2 3 3; 2 3 3]

Both the view and copyto! solutions suggested above allocate. Try this to avoid allocations: copyto!(m, 1, m, 1 + size(m,1), (size(m,2) - 1) * size(m,1)) Or use a for loop.

What is the quickest way to move a subsection of a matrix?

General Usage

Tamas_Papp November 26, 2018, 7:59am 4

It is never clear to me whether the two regions of copyto! or .= can overlap, so I generally avoid this.

1 Like

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What is the quickest way to move a subsection of a matrix?

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