| Basic Characteristics | u b. _ | 
| u b. y gives the linear representation of the obverse of u 
if y is _1; its 
ranks if y 
is 0; and the linear representation of the 
identity function if y is 1 . |  | 
^ b. _1 ^. ^ b. 0 0 0 0 ^ b. 1 $&1@(}.@$) g=: +&2@(*&3@*:) ]y=: g 5 77 g ^:_1 y 5 g b. _1 %:@(%&3)@(-&2) %:@(%&3)@(-&2) y 5 g b. 0 0 0 0