Hi Sameer,
Problem Setup :
Input/Parameter estimation :
A 2D discretized grid, at each center point of the grid, I am estimating the parameter value (e.g. fluid velocity). I am ensuring that the parameters are normalized by setting the lower and upper bounds to be 0. and 1. respectively.
Structurally some of the grid points could have zero-velocity, meaning that it is not hollow at that point. So basically I am trying to cut a pattern on to a thin film structure.
Output/Cost Function :
I have a 1D sensor grid at the outlet for measurements. My measurement distribution mostly resembles a distribution, lets say an gaussian distribution. Nevertheless I am more interested in the slope of this distribution than the values itself. Hence I have a scalar output/cost function. Hence I said my system is under determined in this case. In the meantime, I am exploring what kind of other information, I could give the solver.
My results with this basic setup:
Linear solver ordering AUTOMATIC 1
Cost:
Initial 5.000000e-01
Final 5.000000e-01
Change 0.000000e+00
Minimizer iterations 1
Successful steps 1
Unsuccessful steps 0
Line search steps 0
Time (in seconds):
Preprocessor 0.000359
Residual only evaluation 0.000000 (0)
Line search cost evaluation 0.000000
Jacobian & residual evaluation 0.029389 (1)
Line search gradient evaluation 0.000000
Linear solver 0.000000 (0)
Line search polynomial minimization 0.000000
Minimizer 0.031867
Unfortunately I didn't understand the result.
Initial Cost : 0.5
Residual only evaluation : 0.0
Debugging :
I realised that, during debugging a small change is being added to the parameters. But this small change is not having a perceivable impact on the cost function. But when I manually increase this change value(d_parameter), then I can see a small impact on the cost function. Hence I mentioned in my previous post, that the parameters values might be little insensitive to the cost function. Hence I expected the jacobian value to be too low.
My solution technique :
I am trying to evaluate the continuous parameter values on the discretized grid. At the end have a threshold value, inorder have patterns on my 2D structure.
I am hoping that I was able to give at least a little bit insight onto the problem.
Any ideas and suggestions are welcome.