Understanding display of equations and computation with Symbolics.jl

[ChrisRackauckas]

I am not entirely sure what the questions are here? I haven’t answered because I’m trying to parse what you’re saying and a lot of it doesn’t make sense, so I’m just going to post what I can answer and see if that helps.

@hatmatrix

Is there a better way to contain the scope of symbolic variables? Should they always be used within a let...end block?

If you need them to stay scoped, then yes do that.

@hatmatrix

In this case, care must be taken that the argument to the anonymous function cannot be r as it is now considered a symbol in this namespace (which I found out by accident - that r would remain a symbol within the scope of the anonymous function was expected behavior).

@variables x, y creates lines of code like x = Symbolics.variable(...). I’m not sure how else it could work. It has to create a Julia variable. There’s nothing different about them from a normal Julia variable. It just has dispatches for mathematical operations and display overrides for Latex.

@hatmatrix

assuming that π has not already been associated with Base.pi through a prior calculation (hence requiring the launch of a new Julia instance; otherwise maybe enclose in a let...end block)

That’s just Julia’s standard behavior with shadowing base variables. I just wouldn’t shadow variables exported from Base.