I have a doubt about default arguments. In the Functions documentation it says that I can use optional arguments aswell as defining a function with a simplyfied syntax of y(x)=x**2, but can’t I have such a function with optional parameters? For example this works t=1:0.1:10 y(t,v_0=1,a=-9.8,y_0=0)…

You should include error messages: julia> y.(t,v_0=10) ERROR: MethodError: no method matching y(::Float64; v_0::Int64) Closest candidates are: y(::Any, ::Any, ::Any, ::Any) got unsupported keyword argument "v_0" @ Main REPL[11]:1 y(::Any, ::Any, ::Any) got unsupported keyword argument "v_0"…

Oh I fell for that as well recently. though there is a , in y_vec=y.(t,v_0=10) the v_0= makes Julia start the “keyword section”, so what you wrote is the same as y_vec=y.(t; v_0=10). I felt accepting a , here as well is maybe misleading. As Daniel wrote all your arguments are positional (optional) …

[image] kellertuer: Besides that I am not 100% sure how keywords work together with your broadcasting, but that is maybe a next point to check then. The keyword arguments are not broadcasted over, as far as I can tell: julia> function f(x; v) @show x, v end f (generic function …

The NamedPositionals.jl package allows function calls closer to OP’s intent: using NamedPositionals y1 = (u->@np y(u, v_0=10;)).(t) y2 = (u->@np y(u, v_0=5, a=-1.62;)).(t) y3 = (u->@np y(u, v_0=1, a=-9.8, y_0=7.5;)).(t) I could not get broadcasting to work with the @np macro, hence the broadcastin…

An orthogonal point to consider - I often find that when I’m writing function signatures like that, it’s probably time to make a struct that encodes a bunch of those parameters :person_shrugging:

Inline functions with default parameters

General Usage

stevengj August 24, 2024, 1:58pm 9

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Inline functions with default parameters

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