Group datasets needs option to fill partial variables
This issue was created automatically from an original Mantis Issue. Further discussion may take place here.
Group datasets often creates partial arrays. There should be an option, default on, that makes all arrays the same length, and has an option, default on, to fill these arrays with some variable when none exists. Allow user to fill with a default number (such as done with the calculator). Lets make this number default to 0, but allow the user to change it.