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Hi

check your equation views, there you find the definitions (mostly)

I assume its the norm of E hence the scalar sqrt(Ex^2+Ey^2+Ez^2) where (Ex,Ey,Ez) is your field vector

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Good luck
Ivar

Thank you for your replay.

Best regards

I asked support this question a couple months ago and this is what they said:

"The variable normE is defined by the expression
sqrt(realdot(Ex,Ex)+realdot(Ey,Ey)+realdot(Ez,Ez)), where the operator
realdot(a,b) treats complex numbers a and b as if they were real-valued
vectors of length 2 and returns their dot product (like a shorthand form of
real(a*conj(b)), except in respect to its partial derivatives). More
information on the realdot() operator can be found in the COMSOL
Multiphysics User's Guide on p. 119"

It is a bit more involved that the square root of the sum of squares.

Hi

you are perfectly correct,
because of the possible COMPLEX representations of the E field phasor you need then to use the realdot() operator, this applies several places, not only for E. It all depends in which study you are , thanks for the reminder

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Good luck
Ivar

Hi Ivar,

Can you tell me how to get the complex value E from the comsol. it really annoyed me. I used comsol-matlab (mentioned in the following), but the value what I get is real value (not complex data), it should be the complex data (include phase), right?

Looking ofrward to your reply! thanks very much!!


e.g., if I want to get the Ey value.
yy=postplot(fem,'tridata',{'Ey','cont','internal','unit','V/m'},'solnum',index,'outtype','postdataonly');
the value waht I get is only real data (no imaginary part).

Hi

COMSOL has the complex values stored, but you can only extract a scalar hence when youneed t fetch it in two steps as a real(E)+i*imag(E), and dump it via 2 real values and recombine with the "i" in matlab or EXcel or whatever you use

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Good luck
Ivar

you can export complex fields using "Export" node