Discussion Forum

Hello,

I am currently using the Grad-free operator to try to solve an inversion problem. The problem consists of taking measurements of a magnetic field at the surface. We are making synthetic models in comsol, then using the grad-free optimization to try to solve. I find that the objective function doesn't like the with operator so with an objective function like this:

(real(mod1.intop21(with(2,mf.Hy)))-1.60154e-4)^2

Where this function is trying to minimize the high frequency (defined in our parameter sweep) real part of the magnetic field with the value that was taken from the specific model with a certain Chargeability and conductivity. We have an objective function at each point for the low, high, real, imag parts. So 4 in total for each point.



Warning: Problem encountered during results while solving.
The solution specification is nonscalar or out of range.
- Geometry: 1
- Point: 34
Failed to evaluate expression.
- Expression: with(2,mod1.mf.Hy)
Failed to evaluate expression.
- Expression: with(2,mod1.mf.Hy)
Failed to evaluate expression.
- Expression: mod1.intop21(with(2,mod1.mf.Hy))
Failed to evaluate expression.
- Expression: imag(mod1.intop21(with(2,mod1.mf.Hy)))
Failed to evaluate variable.
- Variable: opt.obj84
- Defined as: ((2.5741099999999998e-012+imag(mod1.intop21(with(2,mod1.mf.Hy))))^2)
Failed to evaluate variable.
- Variable: all obj sum
- Defined as: (opt.obj84+(opt.obj83+(((opt.obj80+(((opt.obj77+(opt.obj76+((opt.obj74+(opt.obj73+(opt.obj72+((opt.obj70+((opt.obj68+(opt.obj67+(opt.obj66+((opt.obj64+(((((((opt.obj57+(((opt.obj54+(opt.obj53+((((opt.obj49+((opt.obj47+((opt.obj45+(opt.obj44+((opt.obj42+(opt.obj41+(opt.obj40+(opt.obj39+((opt.obj37+(((opt.obj34+(opt.obj33+(opt.obj32+(opt.obj31+((opt.obj29+(opt.obj28+(((opt.obj25+(opt.obj24+(((((opt.obj19+(((((opt.obj14+(opt.obj13+(opt.obj12+((opt.obj10+((((opt.obj6+(((opt.obj3+(opt.obj1+opt.obj2))+opt.obj4)+opt.obj5))+opt.obj7)+opt.obj8)+opt.obj9))+opt.obj11))))+opt.obj15)+opt.obj16)+opt.obj17)+opt.obj18))+opt.obj20)+opt.obj21)+opt.obj22)+opt.obj23)))+opt.obj26)+opt.obj27)))+opt.obj30)))))+opt.obj35)+opt.obj36))+opt.obj38)))))+opt.obj43)))+opt.obj46))+opt.obj48))+opt.obj50)+opt.obj51)+opt.obj52)))+opt.obj55)+opt.obj56))+opt.obj58)+opt.obj59)+opt.obj60)+opt.obj61)+opt.obj62)+opt.obj63))+opt.obj65))))+opt.obj69))+opt.obj71))))+opt.obj75)))+opt.obj78)+opt.obj79))+opt.obj81)+opt.obj82)))
Failed to evaluate expression.
- Expression: real(all obj sum)
Failed to evaluate expression.
- Expression: real(all obj sum)

Is there something wrong with my syntax here? Am I going to have to define this is a different way?