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LSOPT Direct Optimization

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    • Deepak Kumar
      Subscriber

      Hello all,

      I am doing direct optimization with GA algorithm.

      This is how i had defined the Termination criteria.
      Note i am using composites with curve matching (MeanSqErr) as my objective.


      As per my Termination criteria, it should stop when 3 same optimums are generated right ? (0.1*30= 3).
      but from the picture you can see that it stops after 5 same values.


      I wanted to know how it terminates.
      Thanks in advance.

    • Anirban Basudhar
      Ansys Employee

      Hi Deepak, the internal LS-OPT tolerance for assessing improvement in objective function is 1e-9, which is lower than the digits appearing in the table. Therefore, it is entirely possible that the first change was greater than 1e-9; you just don't see it in the table due to round off. Even without that you would have seen 4 repeated values (1st value + another 3 repetitions). 

    • Deepak Kumar
      Subscriber

      Hello Anirban,

      Thank you for the information. I have understod now

      one last doubt what does "Space for -1 doubles needed" error mean   ?
      Because of this i cant access histories created in the result simulations.

      Thank you. 

    • Anirban Basudhar
      Ansys Employee

      Hi Deepak, that indicates an issue with memory allocation inside the software. It could have something to do with the problem definition or overloaded system. Can you 1. try it again, 2. try it on a different system, 3. send your example to support for debugging in that order?

    • Deepak Kumar
      Subscriber

      Hi Anirban,

      Thank you.
      I will try these suggestions.

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