Thank you so much for answering! 

To confirm again, is it correct that in aedtplt file, nodes store the electric field values of mesh elements of the object? 

It would be great if I can do it using the fields calculator in HFSS. Would you please let me know how I should start? I read the help document, but it doesn't include any information or examples regarding the percent calculation or mention any conditonal functions ( i.e. greater than or less than).   

I tried to submit a support request, but it asked for my Siebel eCustomer Portal Innovation Pack 2013 and wouldn't let me sign in or reset the password. I clicked on "Submit", but it didn't take me to Sign in page...