I have a type-stability question. In my 2D axisymmetric ray tracing code, I define an array of surfaces that has the type Union{Cone, Plane}, like surfaces = Matrix{Union{Cone, Plane}}(undef, 100, 2) All of them should in principle be cones, but due to small errors from a discretization earlier on…

Cone and Plane are abstract types. Only unions of isbits types are fast. If you are using 64 bits floats then you probably want the type to be Union{Cone{Float64},Plane{Float64}}.

Array of union causing 10x slowdown

General Usage Performance

jling December 7, 2022, 2:56am 2

maybe Allocation and slow down when # of types involved increase (slower than C++ virtual methods)

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Array of union causing 10x slowdown

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