[GAP Forum] Group of units of finite gaussian integers

[sopsku]

Dear Forum,

How do I define the group of units of Z_n[i] in GAP? In particular I
ultimately want to determine isomorphism classes of these groups. I assume
that once I have properly defined the group of units I can then just use
StructureDescription, but any help in actually defining the isomorphism
would be appreciated.  

Thank you for your help. 

    Ron