Calculating the absorption coefficient in CST ?

[mahsa.a.j]

Hello everyone
I simulated the structure with CST and since my structure is periodic in the direction of x and y, I used the floquet port or plan wave.
I want to derive absorption, transmission and reflection coefficients.
If I use the, Calculate Reflectance Transmittance and Absorbance in optical menu in template based post-processing, the following Error appears:
Error in evaluating define function:
"Please define at least one port
How can I resolve this problem?"
Pleas help me

 

[gyz182]

Error seems to suggest there is no port defined in your simulation? How did you assign the ports?

Does the error only occur if you use TBPP? I don't think that's the case, but I would look at how the port is defined