I run the code below, and find we need more times when manipulate the array at the first time. I want to know why, and can we avoid it? function test() a = Vector{ComplexF64}(undef, 2^25) @time fill!(a, 0.0+0.0im) @time fill!(a, 1.0+0.0im) @time fill!(a, 2.0+0.0im) println() end functio…

Why need to pay more time when access the array at first time?

Oscar_Smith August 5, 2024, 3:53pm 2

This is happening because the first time you touch the memory it is being brought into your CPUs cache. Julia isn’t doing anything different here.

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