UNARY-/

reciprocal function 
Major Section:  PROGRAMMING

Completion Axiom: 

(equal (unary-/ x)
       (if (and (acl2-numberp x)
                (not (equal x 0)))
           (unary-/ x)
         0))

Guard for (unary-/ x): 

(and (acl2-numberp x)
     (not (equal x 0)))
Notice that like all arithmetic functions, unary-/ treats non-numeric inputs as 0.

Calls of the macro / on one argument expand to calls of unary-/; see /.