Jonnie Diegelman

Should `unflatten` unwrap `Fixed` values?

3

I am finally getting around to #30. In doing so I noticed: ```julia julia> x = (1, 2.0, fixed(3.0)) (1, 2.0, ParameterHandling.Fixed{Float64}(3.0)) julia> v, unflatten = flatten(x); julia> unflatten(v) (1,...

Feature Request: `flatten_only`

11

One of the biggest problems I have when handling parameters (whether I'm using ComponentArrays, Functors, ParameterHandling, etc.) is that I often only want to optimize (or do some other analysis)...

Lagrangian and Hamiltonian Systems

2

Based on [this](https://discourse.julialang.org/t/solving-symbolic-equations/57978/6) here's a first crack at how to handle Lagrangian systems. ```julia using Symbolics, ModelingToolkit, DifferentialEquations ∂_∂(x) = y -> expand_derivatives(Differential(x)(y)) function LagrangianSystem(L, q̇, q, p, t; Q...