You are very welcome. I hope that your collection of notebooks continues to
grow.
On Monday, 1 December 2014 14:09:22 UTC+1, Christoph Ortner wrote:
>
> Hi Valentin,
>
> This is extremely helpful - thank you for providing these tweaks. I hope
> you don't mind if I incorporate this.
>
> (And sorry for the typos - I am normally better at testing.)
>
> Christoph
>
>
>
>
> On Sunday, 30 November 2014 20:54:40 UTC, Valentin Churavy wrote:
>>
>> I found a second error in lj_cstyle
>>
>> t is calculated wrongly:
>> t = 1./s*s*s != 1/s^3
>>
>> It probably should be t = 1.0 / (s * s * s)
>>
>> t = 1.0 / (s*s*s)
>> E += t*t - 2.*t
>> dJ = -12.0 *(t*t - t) / s
>>
>> cstyle is on my machine still two times faster then my optimized variant
>> of jl_pretty
>>
>> Best Valentin
>>
>> On Sunday, 30 November 2014 20:54:58 UTC+1, Valentin Churavy wrote:
>>>
>>> Nice work!
>>>
>>> Regarding the pretty Julia version of Lennard-Jones MD.
>>>
>>> You can shape of another second (on my machine) by not passing in the lj
>>> method as a parameter, but directly calling it.
>>>
>>> I tried to write an optimize version of your lj_pretty function by
>>> analysing it with @profile and rewriting the slow parts. You can see my
>>> results here: https://gist.github.com/vchuravy/f42f458717a7a49395a5
>>> I went step for step through it and applied one optimization at a time.
>>> You can also see the time computation time spend at each line as a comment.
>>> Mostly I just removed temporary array allocation and then applied your math
>>> optimization.
>>>
>>> One question though. In lj_cstyle(x) you calculate dJ = -12.*(t*t - t)
>>> * s , shouldn't it be dJ = -12.*(t*t - t) / s?
>>>
>>> Kind regards,
>>> Valentin
>>>
>>>
>>>
>>>
>>>
>>> On Sunday, 30 November 2014 12:51:31 UTC+1, Christoph Ortner wrote:
>>>>
>>>> Belated update to this thread:
>>>>
>>>> I have now finished a first draft of three tutorial-like numerical PDE
>>>> notebooks; they can be viewed at
>>>> http://homepages.warwick.ac.uk/staff/C.Ortner/index.php?page=julia
>>>> I have two more coming up in the near future, one on spectral methods,
>>>> the other on an optimisation problem. For the moment, I am using them
>>>> primarily for my research group to learn Julia, and to show it to
>>>> colleagues when they are interested.
>>>>
>>>> Q1: May I use the Julia logo on that website, as well as for any
>>>> tutorials / courses that I teach based on Julia?
>>>>
>>>> Q2: Eventually I think it would be good to have a "Julia Examples" page
>>>> such as
>>>> http://www.mathworks.com/examples/
>>>>
>>>> Q3: I'd of course be interested in feedback.
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
