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Hi,

I am trying to build a 3D diode model, but when I refine the mesh I get the following error:

Adaptive solver stopped. Failed to find a solution. Attempt to evaluate negative power of zero. Function: ^ Failed to evaluate expression. Expression: (2d(comp1.semi.mf,X))(0.5((((d(comp1.semi.mf,X)^2)+(d(comp1.semi.mf,Y)^2))+(d(comp1.semi.mf,Z)^2))^(-0.5))) Failed to evaluate Jacobian of expression. Expression: sqrt(((d(comp1.semi.mf,X)^2)+(d(comp1.semi.mf,Y)^2))+(d(comp1.semi.mf,Z)^2)) Failed to evaluate Jacobian of expression. Expression: comp1.semi.intadapt(sqrt(d(comp1.semi.mf,X)^2+d(comp1.semi.mf,Y)^2+d(comp1.semi.mf,Z)^2)) Returned solution is not converged. Not all parameter steps returned.

I was trying to use the Adaptation and Error Estimates functionality. In the Functional field, I entered:

root.comp1.semi.intadapt(sqrt(d(root.comp1.semi.mf,root.X)^2 + d(root.comp1.semi.mf,root.Y)^2 + d(root.comp1.semi.mf,root.Z)^2))

Then I changed it to:

root.comp1.semi.intadapt(sqrt(d(root.comp1.semi.mf,root.X)^2 + d(root.comp1.semi.mf,root.Y)^2 + d(root.comp1.semi.mf,root.Z)^2 + epssmall))

to avoid division by zero. However, whenever I run the computation, the parameter** eps_small** is automatically removed from the expression, even if I try to save it. Could you please help me understand why this happens and how to keep the parameter in the expression?

Thanks a lot for your help.

Best regards,