I was surprised that the following code reports an allocation when looking up a Float64 value from a Dict{Int64,Float64} using BenchmarkTools n = 1_000_000 d = Dict(i=>rand() for i in 1:n); @btime d[42] # 19.346 ns (1 allocation: 16 bytes) even more strangely, if I make a Dict{Int64,String} inste…

Lookup in Dict{Int,Float64} allocates

kristoffer.carlsson January 31, 2022, 12:16pm 2

Don’t benchmark in global scope like that. See some of the top tips in Performance Tips · The Julia Language.

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