Hello, I am working with the DifferentialEquations package to play around some differential equations involving angles. Instead of letting everything go on as a normal float and just afterwards reduce everything modulo 2pi for visualisation, i wanted to try to go the julian way and define a small …

You should find an inspiration in manual describing the implementation of rational number. https://docs.julialang.org/en/v1/manual/conversion-and-promotion/

This is extremely interesting but the @forward macro seems to not retain the type as in struct Angle <: Real x::Float64 end @forward Angle.x Base.sqrt then typeof(Base.sqrt(Angle(1))) == Float64 #true and that is not really what i need. Moreover, using forward on Base.:+ raises a MethodErro…

True, maybe eval would be more the case here. for single_param_function in (:(Base.sqrt), :(Base.sin)) eval(quote function $(single_param_function)(a :: Angle) return Angle($(single_param_function)(a.x)) end end) end Someone with better knowledge of metaprogramm…

[image] cshen: Angle(x::Real) = Angle(x % 2pi) Note that you will get more accurate results by using mod2pi(x) instead of x % 2pi (since the latter uses 2pi, a Float64 approximation of the actual number 2π).

Is the sine of an angle another angle or just a number? If you don’t need it to be an angle, then simply defining Base.float for your type will work for a lot of functions that use this as their fallback. julia> Base.float(a::Angle) = a.x julia> sin(Angle(1)) 0.8414709848078965

Julian way of defining custom numeric types

New to Julia

Henrique_Becker January 24, 2021, 5:28pm 3

Also, I think you can benefit from the macro @forward that I describe in this reply of mine.

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Julian way of defining custom numeric types

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