Optimization query

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Divyam Verma

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Nov 5, 2021, 2:30:40 AM11/5/21
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Hi,

I am running an optimization problem in SUAVE where there is no objective function. But these are the termination statements: 

Singular matrix C in LSQ subproblem    (Exit mode 6)
            Current function value: 0.0
            Iterations: 1
            Function evaluations: 4
            Gradient evaluations: 1

instead of this:

Optimization terminated successfully. (Exit mode 0) 
              Current function value: 0.0 
              Iterations: 6 
              Function evaluations: 43
              Gradient evaluations: 6

What seem to be the problem, because I'm confused. Is it because the inputs are going towards a maximum value since the first iteration?

Thanks,
Divyam


Divyam Verma

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Nov 5, 2021, 7:55:28 AM11/5/21
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Hi,

Another problem which I am having is my design variables are not changing. I have kept wing span as a single design variable with the initial value at 3.5 m , [lb,ub]=[2,5] m and scale=3.5 m. But the optimization problem is not changing the design variables and is constant at 3.5 m. It is only running for one iteration.
Could you please help me with this?

Thanks,
Divyam

ebot...@gmail.com

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Nov 7, 2021, 9:27:01 PM11/7/21
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Hi,
The result you're getting above (Exit mode 6) would also indicate the design variable are not changing the constraint values.

I suspect the aliases have a typo. Check those. But it could also be something in the procedure if you have a sizing function that overwrites the span. I suggest you print the vehicle somewhere in the Procedure.py. Then run problem.objective([number,number...]) with numbers filled in to make sure that the values are changing when you change the numbers.

-Emilio

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