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- 21:47ChrisRackauckas commented #1193
- 21:47ChrisRackauckas edited #1193
- 21:46ChrisRackauckas reopened #1193
- 21:44
kanav99 on gh-pages

build based on 4078de6 (compare)

- 21:40YingboMa edited #508
- 21:40YingboMa edited #508
- 21:39YingboMa synchronize #508
- 21:39
YingboMa on skipzerofil

Interpolate fill_array_with_zer… fill_zero -> fillzeros (compare)

- 21:39
kanav99 on gh-pages

build based on ef3f5d4 (compare)

- 21:34shashi opened #509
- 21:33
shashi on fix-consting

fix when op is a Variable or Ex… (compare)

- 21:33
kanav99 on gh-pages

build based on 8a0d245 (compare)

- 21:32
shashi on fix-505

fix when op is a Variable or Ex… (compare)

- 21:32
YingboMa on skipzeros

- 21:32YingboMa closed #504
- 21:32YingboMa commented #504
- 21:31YingboMa review_requested #508
- 21:28YingboMa opened #508
- 21:27
shashi on skipzerofil

Add fill_zero kwarg to build_fu… (compare)

- 21:24
kanav99 on gh-pages

build based on e65ed6b (compare)

[slack] <chrisrackauckas> that will need an issue

[slack] <chrisrackauckas> algorithm dependent

[slack] <chrisrackauckas> it's something computed as part of the ODE solver, so it's not a parameter

[slack] <chrisrackauckas> it's a local error estimate

[slack] <Wei> Thanks. For a SDEproblem, is it possible that if I set a larger

`g`

, the solver need more iterations and smaller `dt`

to meet the `abstol`

and `reltol`

requirement? It means for the same `abstol`

and `reltol`

, the larger of `g`

, the increasing of iterations and smaller adaptive `dt`

?
[slack] <chrisrackauckas> yes

[slack] <chrisrackauckas> that's quite common

[slack] <Wei> Ok, I got it. I don't know before. But I realized when I increasing the

`g`

value and keeping the other same, the solver needs more time to return a result.
[slack] <Wei> Ok, I got it. Thanks.

[slack] <chrisrackauckas> it should

[slack] <simeondavidschaub99> The following example doesn't:

```using ModelingToolkit

@variables t x(t)

@derivatives ∂ₜ'~t

L = .5 * ∂ₜ(x)^2 - .5 * x^2

euler_lagrange(L, x) = expand_derivatives(Differential(x)(L) - ∂ₜ(Differential(∂ₜ(x))(L)))

julia> euler_lagrange(L, x)

derivative(0.5 * derivative(x(t), t) ^ 2 + -0.5 * x(t) ^ 2, x(t)) + -1 * derivative(derivative(0.5 * derivative(x(t), t) ^ 2 + -0.5 * x(t) ^ 2, derivative(x(t), t)), t)```

[slack] <chrisrackauckas> is that latest master?

[slack] <simeondavidschaub99> Yes:

```
``(@v1.5) pkg> st ModelingToolkit
Status
```

~/.julia/environments/v1.5/Project.toml`[961ee093] ModelingToolkit v3.13.0`

https://github.com/SciML/ModelingToolkit.jl.git#master````
[slack] <simeondavidschaub99> Just checked out the latest master

[slack] <Adam Gerlach> @AlCap23 In case you haven't seen this "Forecasting Sequential Data Using Consistent Koopman Autoencoders" may interest you. Includes Python code https://github.com/erichson/koopmanAE

[slack] <chrisrackauckas> I think @shashi fixed that

[slack] <chrisrackauckas> hashing operations is good

[slack] <chrisrackauckas> hashing variables is weird IIRC

[slack] <isaacsas> That's the opposite of my experience.

[slack] <shashi> yeah they should be safe in dicts

[slack] <chrisrackauckas> we have a hash defined for operations and it's the one that's tested?

[slack] <isaacsas> OK, interesting. I think all the MT code I've used with

`Dict`

s used `Variable`

s (because previously I had issues with `Operation`

s). (I'm still trying to figure out this `issetequal`

not working issue, for which it was suggested that maybe the problem is not having `hash`

defined, but I guess it is something else.)
[slack] <isaacsas> Good to know that should be safe to do going forward at least.

[slack] <chrisrackauckas> I think so

[slack] <chrisrackauckas> the DEBio docs probably are worth a few pages, at least for tutorials and such, right?

[slack] <chrisrackauckas> JumpSystem and all of that is MTK, but I think ReactionSystem and the DSL for ReactionSystem might make sense as what Cataylst is?

[slack] <chrisrackauckas> I think that would make more sense then double docs for ReactionSystem

[slack] <isaacsas> It is a bit weird to have some stuff in MT and some in DEBio

[slack] <chrisrackauckas> I thought the split was, abstract systems in MTK

[slack] <chrisrackauckas> I think instead it's, abstract systems for symbolic numerics in MTK, and abstract systems for domains in a domain modeling package

[slack] <chrisrackauckas> so ODESystem MTK, JumpSystem MTK, ReactionSystem is it's own whole world