@btime x/y setup=(x=rand(ComplexF64);y=rand(ComplexF64)); gives 9.853 ns (0 allocations: 0 bytes) while function frac(x::ComplexF64, y::ComplexF64) y2=y.re^2+y.im^2 return Complex((x.re*y.re+x.im*y.im)/y2, (x.im*y.re-x.re*y.im)/y2) end @btime frac(x,y) setup=(x=rand(ComplexF64);y=rand(C…

The built-in complex division is unreasonably slow

Oscar_Smith November 30, 2022, 3:19am 2

the short answer is getting good accuracy for these is hard. If you look at @btime @fastmath x/y you’ll see faster results results.

1 Like

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