Good work! For eventual sparse Jacobians you'll probably want to have a
look at the various Julia automatic differentiation packages that folks
have put together. Many of their uses have been confined to optimization
(and maybe also solving nonlinear systems of equations?) so far, but DAE
solvers should absolutely be able to leverage the same functionality.
On Tuesday, May 6, 2014 2:41:05 PM UTC-7, Paweł Biernat wrote:
>
> DASSL is now in the official package list! You can install it via
> Pkg.add("DASSL").
>
> W dniu wtorek, 6 maja 2014 16:25:34 UTC+2 użytkownik Tomas Lycken napisał:
>>
>> Re licensing:
>>
>> I don't think it can be considered an implementation from scratch if
>> you've looked at the code, unfortunaltely.
>>
>> However, the origin of the file seems to be a group at Polytecnico da
>> Bari [1] and they have graciously released the code into public domain [2],
>> so we're all good anyway =)
>>
>> [1]: http://www.dm.uniba.it/~testset/solvers/dassl.php and also
>> http://www.dm.uniba.it/~testset/testsetivpsolvers/
>> [2]: http://www.dm.uniba.it/~testset/report/dassl.pdf
>>
>> // Tomas
>>
>> On Tuesday, May 6, 2014 12:07:01 PM UTC+2, Viral Shah wrote:
>>>
>>> Sure. Usually what we do is have people submit a few PRs and once they
>>> have the hang of it, we give push access.
>>>
>>> -viral
>>> On 06-May-2014 3:08 pm, "Paweł Biernat" <[email protected]> wrote:
>>>
>>>> Could I get the push access to the METADATA repo?
>>>>
>>>> W dniu wtorek, 6 maja 2014 10:59:46 UTC+2 użytkownik Viral Shah napisał:
>>>>>
>>>>> Good idea - ODE.jl is certainly the place for this.
>>>>>
>>>>>
>>>>> On Tue, May 6, 2014 at 1:51 PM, Ivar Nesje <[email protected]> wrote:
>>>>>
>>>>>> I think a DAE solver would be a great fit for ODE.jl. Currently I
>>>>>> think it will be best to develop it outside, until a few important
>>>>>> cleanups
>>>>>> is performed on the ODE solvers. The state of ODE.jl is between a
>>>>>> breaking
>>>>>> API discussion and implementation of that described API. It would be
>>>>>> very
>>>>>> nice if you could read some of the
>>>>>> discussion<https://github.com/JuliaLang/ODE.jl/search?q=api&ref=cmdform&type=Issues>
>>>>>> and
>>>>>> documentation<https://github.com/JuliaLang/ODE.jl/blob/master/doc/api.md>
>>>>>> and
>>>>>> comment from your point of view. Some consensus has been reached, but
>>>>>> there
>>>>>> are still possible to argue for different solutions.
>>>>>>
>>>>>> Ivar
>>>>>>
>>>>>> kl. 10:02:40 UTC+2 tirsdag 6. mai 2014 skrev Alex følgende:
>>>>>>
>>>>>>> Or submit a PR for including it in ODE.jl :-)
>>>>>>>
>>>>>>> Best,
>>>>>>>
>>>>>>> Alex.
>>>>>>>
>>>>>>>
>>>>>>> On Tuesday, 6 May 2014 09:57:34 UTC+2, Viral Shah wrote:
>>>>>>>>
>>>>>>>> It's great to see a DASSL implementation in Julia! Do register it
>>>>>>>> with METADATA.
>>>>>>>>
>>>>>>>> -viral
>>>>>>>>
>>>>>>>> On Tuesday, May 6, 2014 12:41:20 PM UTC+5:30, Paweł Biernat wrote:
>>>>>>>>>
>>>>>>>>> For the last several weeks I have been implementing [1] a DASSL
>>>>>>>>> algorithm in Julia. The DASSL algorithm was developed by Linda
>>>>>>>>> Petzold in late 80s to solve Differential Algebraic Equations (DAE)
>>>>>>>>> and its Fortran 77 implementation is one of the most popular DAE
>>>>>>>>> solvers. My implementation in Julia bases mainly on a book [3] and
>>>>>>>>> partly on the source of the original implementation [2] (mostly in
>>>>>>>>> places where the book was ambiguous). I tried to mimic the
>>>>>>>>> behavior
>>>>>>>>> of the original implementation as much as I could but my code is
>>>>>>>>> not
>>>>>>>>> in a one to one correspondence with the original (I aimed at
>>>>>>>>> readability of the algorithm), so don't be surprised if you get
>>>>>>>>> slightly different results from both versions.
>>>>>>>>>
>>>>>>>>> This is my first larger project in Julia so don't expect high end
>>>>>>>>> quality or performance, but I tested my implementation for
>>>>>>>>> convergence
>>>>>>>>> on various simple index-0 and index-1 problems and it works just
>>>>>>>>> fine. That said, I am open to any critique and suggestions, and
>>>>>>>>> any
>>>>>>>>> help with improving the code. Ultimately, I would like to see this
>>>>>>>>> code merged into the ODE.jl library, if the maintainers of the
>>>>>>>>> latter
>>>>>>>>> allow it.
>>>>>>>>>
>>>>>>>>> [1] https://github.com/pwl/dassl.jl
>>>>>>>>> [2] http://www.netlib.org/ode/ddassl.f
>>>>>>>>> [3] "Numerical Solution of Initial'Value Problems in
>>>>>>>>> Differential-Algebraic Equations" K. E. Brenan, S. L. Campbell, L. R.
>>>>>>>>> Petzold
>>>>>>>>>
>>>>>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> -viral
>>>>>
>>>>
