I have these three ways of creating a zero vector. module m function zeroout(a) @inbounds Threads.@threads for k in eachindex(a) a[k] = 0.0 end end N = 1000000000 println("a = fill(0.0, N);") @time a = fill(0.0, N); println("undefined, a .= 0.0;") @time a = Vector{Float64}(undef,…

They have optimized implementations that branch on sizes, for example. They’ll use noon-temporal stores when the memory is too big to fit in cache, for example. It should in general be the fastest way to set memory (but calloc should still be better for 0).

Fastest way of getting a long zero vector?

General Usage

stevengj March 14, 2024, 6:01pm 2

You could use calloc. See e.g. Faster zeros with calloc and ArrayAllocators.jl

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Fastest way of getting a long zero vector?

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