I used to be able to run the attached file before. However, now when I try to run the nested sweep it gives me concatenation error. I am using the nested sweep to change incidence angle and wavelength. I am using the newest FDTD version. I tried having an override mesh but this did not help since each simulation gives me one number only (reflection value). I read the other posts about the same error but they did not help. I am wondering if you have an idea about why I might be having this error.
Gratings - Copy.fsp (328.6 KB)