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amusiienko1-Visitor
1-Visitor
December 27, 2020
Solved

System of ODE and Minerr data fit optimization

  • December 27, 2020
  • 1 reply
  • 3754 views

Hello, everyone. I wrote a simple program that solves 5 differential equations. Further, I fit experimental data with MINERR. 

 

It works but it works very slow.  Does anyone know how to do it a bit faster?

 

Thank you in advance! Program is attached

amusiienko_0-1609098421368.png

 

    Best answer by Werner_E

    I notice that your odesolve-block returns 8 functions, but in your minerr-solve block you assign the result to a vector with just seven variables. Thats sure possible - are you sure you don't need p022.

    I can't check your sheet because I always get the error message that Excel is busy, can't be activated and I shall try in a few seconds again.

    I have Excel 2016 installed and I see in the task manager that its invoked. Not sure whats going on.

     

    1 reply

    W
    Werner_E25-Diamond I
    25-Diamond I
    December 28, 2020

    Your minerr-solveblock calls the odesolve-solve block (function F) six times for every iteration, which is quite inefficient.

    The modification seen in the pic below should speed up the calculation by the factor 6.

    Werner_E_0-1609123148079.png

    I turned the solve block into a function just to be able to determine and compare the execution time of both versions.

      W
      Werner_E25-Diamond I
      25-Diamond I
      December 28, 2020

      I just finished timing the two versions and the speed gain with my suggested modification is indeed a little bit more than factor 6.

      Werner_E_0-1609124642976.png

      P6 sheet (with auto-calc disabled) attached

       

        A
        amusiienko1-VisitorAuthor
        1-Visitor
        December 28, 2020

        Oh, interesting you have called function in vector format. That is interesting.

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