DiffEqOperators symbolic tutorial throwing error

Specific Domains Numerics
1

Hi Everyone: the SciML ecosystem looks amazing. I’m just getting started with both Julia and these packages. The tutorial DiffEqOperators gives the following error:

Lines

# Method of lines discretization
dx = 0.1
order = 2
discretization = MOLFiniteDifference([x=>dx],t)

# Convert the PDE problem into an ODE problem
prob = discretize(pdesys,discretization)

Error
TypeError: in isa, expected Type, got a value of type typeof(IntervalDomain)

Stacktrace:
[1] symbolic_discretize(pdesys::PDESystem, discretization::MOLFiniteDifference{Vector{Pair{Num, Float64}}, Num})
@ DiffEqOperators C:\Users\greg.julia\packages\DiffEqOperators\6CWxd\src\MOLFiniteDifference\MOL_discretization.jl:48
[2] discretize(pdesys::PDESystem, discretization::MOLFiniteDifference{Vector{Pair{Num, Float64}}, Num})
@ DiffEqOperators C:\Users\greg.julia\packages\DiffEqOperators\6CWxd\src\MOLFiniteDifference\MOL_discretization.jl:350
[3] top-level scope
@ In[13]:2
[4] eval
@ .\boot.jl:360 [inlined]
[5] include_string(mapexpr::typeof(REPL.softscope), mod::Module, code::String, filename::String)
@ Base .\loading.jl:1094

Hopefully it is helpful for me to post this here. Let me know if there is a fix.

Thanks!

2

That needs to be updated for Add domains by tinosulzer · Pull Request #245 · JuliaSymbolics/Symbolics.jl · GitHub

3

Thanks! Let me know if there are next steps for me (or wait for an update). I’m unclear if “That needs to be updated” means the tutorial, the source code, the package, or something else needs to be updated. Thanks.

4

See that pull request. It needs to update to using Interval, in the docs and maybe some in the package. This is to be expected though since the tutorial has a big bold “this is pre-alpha” on the top! But this is rather easy to fix, so if you want to dive in feel free to open a PR. It’s mostly just a find/replace.

5

Thanks for the clarification, I saw the pre-alpha flag. I’ll see if I can understand the find/replace sufficiently to help out.