How can I list VMAX Storage Groups that are NOT used ?

All:

I discovered that our VMAX has a LOT of Storage Groups that are no longer part of Masking Views.  I guess the previous guys "reclaimed" space from servers and reclaimed old servers that were retired by erasing the Masking Views, but they never erased the Storage Groups.

Is there a command that will show me the Storage Groups that are NOT part of Masking Views?

I can get a list of all of my Storage Groups and then get a list of all of my Masking Views and compare them, but that's a little tedious....

    Stuart