Correct, but using the same procedure you could say create a second electrical “dummy” input and copy it to the output or view it in the work space to copy the data structure.
The pdf here:
https://optiwave.com/wp-content/uploads/2014/03/Matlab-Electrical-Example.pdf?76994c
Outlines the data structure, but personally I find it easier to just view it directly in Matlab and play around with it. It might also be helpful if you are not familiar with Matlab data structures to read their help on the subject:
http://www.mathworks.com/help/matlab/ref/struct.html
You can learn the syntax for accessing and creating data structures there as well.
Cheers!