For those who haven't visited Yonex Japan website, pls follow a link below to see Double/Single and Attack/Defense style map for choosing right racket.
For Racket;
N= Smash/Attack player,
S= Receive/Defense player,
W= Double player,
E= Single player,

For String;
N= Hardhitter
S= Control player
W= Durability
E= Repulsion

http://www.yonex.co.jp/badminton/feature/mp/style.html