julia> using BenchmarkTools julia> function sum1(num) total = 0 for i in num total += i end return total end sum1 (generic function with 1 method) julia> a = collect(1:1000); julia> @btime b = sum(a) 99.192 ns (1 allocation: 16 bytes) 5005…

You seem to be interpolating a at some points and not at others, this could probably affect timing. When the input is a range type I guess the standard sum dispatches to a method using some summation formula, e.g. S(n)=n*(n+1)/2, or similar. Not sure why sum1 also improves that much, 2ns seems like…

Why the function sum1 is faster than builtin sum

General Usage Performance

GunnarFarneback September 20, 2023, 10:54am 12

No, I don’t.

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Why the function sum1 is faster than builtin sum

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